armstrong called grip essentially squeeze bore inches bore muzzle end slightly smaller diameter centered shell left barrel time slightly swaged lead coating reducing diameter slightly improving ballistic qualities french canon de mod le first modern artillery piece armstrong 's system adopted initially special service field initially produced smaller artillery pieces pounder nbsp mm mountain light field guns pounder nbsp mm guns


per minute target either shrapnel melinite high explosive miles away firing rate could even reach close rounds per minute albeit short time highly experienced crew rates contemporary bolt action rifles could match gun used cased ammunition breech loading modern sights self contained firing mechanism hydro pneumatic recoil dampening indirect fire indirect fire firing projectile without relying direct line sight gun target possibly dates back

Applied science
Military sciences
Artillery


th century early battlefield use indirect fire may occurred paltzig july russian artillery fired tops trees battle waterloo battery royal horse artillery fired shrapnel indirectly advancing french troops russian lieutenant colonel kg guk published ''indirect fire field artillery'' provided practical method using aiming points indirect fire describing essentials aiming points crest clearance corrections fire observer years later richtfl che lining plane sight invented


germany provided means indirect laying azimuth complementing clinometers indirect laying elevation already existed despite conservative opposition within german army indirect fire adopted doctrine early goertz germany developed optical sight azimuth laying quickly replaced lining plane english became 'dial sight' uk 'panoramic telescope' us british halfheartedly experimented indirect fire techniques since onset boer war first apply theory practice although


improvise without lining plane sight ref name evolution ref next years leading world war techniques indirect fire became available types artillery indirect fire defining characteristic th century artillery led undreamt changes amount artillery tactics organisation techniques occurred world war implication indirect fire improving guns increasing range gun target increased time flight vertex trajectory result decreasing accuracy increasing distance


target mean point impact shells aimed caused increasing effects non standard conditions indirect firing data based standard conditions including specific muzzle velocity zero wind air temperature density propellant temperature practice standard combination conditions almost never existed varied throughout day day day greater time flight greater inaccuracy added complication need survey accurately fix coordinates gun position provide accurate orientation guns


course targets accurately located air photo interpretation techniques enabled ground survey techniques could sometimes used cm field howitzers world war center methods correcting firing data actual conditions often convoluted availability data actual conditions rudimentary non existent assumption fire would always ranged adjusted british heavy artillery worked energetically progressively solve problems late onwards early effective processes place field heavy artillery processes


enabled 'map shooting' later called 'predicted fire' meant effective fire could delivered accurately located target without ranging nevertheless mean point impact still tens yards target centre aiming point precision fire good enough concentrations barrages processes remain use st century refinements calculations enabled computers improved data capture non standard conditions british major general henry hugh tudor pioneered armour artillery cooperation breakthrough battle cambrai improvements providing using data


non standard conditions propellant temperature muzzle velocity wind air temperature barometric pressure developed major combatants throughout war enabled effective predicted fire effectiveness demonstrated british cambrai germany following year operation michael major general jba bailey british army retired wrote ref jba bailey ''field artillery firepower'' estimated french soldiers casualties friendly artillery fire four years world war precision guided artillery excalibur guided artillery shell modern artillery obviously distinguished long range firing


explosive shell rocket mobile carriage firing transport however important characteristic use indirect fire whereby firing equipment aimed without seeing target sights indirect fire emerged beginning th century greatly enhanced development predicted fire methods world war however indirect fire area fire suitable destroying point targets primary purpose area suppression nevertheless late precision guided munitions started appear notably us nbsp mm copperhead


properly designated small arms rather artillery albeit indirect fire small arms term also came include coastal artillery traditionally defended coastal areas seaborne attack controlled passage ships advent powered flight start th century artillery also included ground based anti aircraft batteries term artillery traditionally used projectiles internal guidance systems preferring term missilery though modern artillery units employ surface surface missiles advances terminal guidance systems small munitions allowed large caliber guided projectiles developed blurring distinction ammunition one


important roles logistics supply munitions primary type artillery consumable storage ammunition dump arsenal magazine provision fuzes detonators warheads point artillery troops assemble charge projectile bomb shell round artillery ammunition comprises four components fuze projectile propellant primer fuzes fuzes devices initiate artillery projectile either detonate high explosive filling eject cargo illuminating flare smoke canisters examples official military spelling fuze broadly


four main types impact including graze delay mechanical time including airburst proximity sensor including airburst programmable electronic detonation including airburst artillery fuzes nose fuzes however base fuzes used armour piercing shells squash head high explosive squash head hesh high explosive plastic hep anti tank shells least one nuclear shell non nuclear spotting version also used multi deck mechanical time fuze fitted base impact fuzes armies remain standard fuze projectiles default action normally 'superquick' 'graze'


action allows penetrate light cover others 'delay' delay fuzes allow shell penetrate ground exploding armor concrete piercing ap cp fuzes specially hardened world war later ricochet fire delay graze fuzed shells fired flat angle descent used achieve airburst shells fitted fuzes airburst fuzes usually combined airburst impact function however introduction proximity fuzes airburst function mostly used cargo munitions example shrapnel illumination smoke


larger calibers anti aircraft artillery almost always used airburst airburst fuzes fuze length running time set done firing using either wrench fuze setter pre set required fuze length early airburst fuzes used igniferous timers lasted second half th century mechanical time fuzes appeared early part century required means powering thiel mechanism used spring escapement ie 'clockwork' junghans used centrifugal force gears dixi used centrifugal force balls


electronic time fuzes started replacing mechanical ones use cargo munitions proximity fuzes two types photo electric radar former successful seems used british anti aircraft artillery 'unrotated projectiles' rockets world war ii radar proximity fuzes big improvement mechanical time fuzes replaced mechanical time fuzes required accurate calculation running time affected non standard conditions requiring burst ground slightly wrong rounds


ground bursts deliver greater proportion useful fragments deliver terrain prone soldier would protected ground bursts however proximity fuzes suffer premature detonation moisture heavy rain clouds led 'controlled variable time' cvt world war ii fuzes mechanical timer switched radar seconds expected impact also detonated impact proximity fuze emerged battlefields europe late december become known us artillery 's christmas present much


appreciated arrived battle bulge also used great effect anti aircraft projectiles pacific ''kamikaze'' well britain v flying bombs electronic multi function fuzes started appear around using solid state electronics relatively cheap reliable became standard fitted fuze operational ammunition stocks western armies early versions often limited proximity airburst albeit height burst options impact offered go go functional test fuze setter later versions introduced induction fuze setting testing


instead physically placing fuze setter fuze latest junghan 's dm u provide options giving superquick delay choice proximity heights burst time choice foliage penetration depths new type artillery fuze appear soon addition functions offer course correction capability full precision sufficient significantly reduce dispersion shells ground projectiles nuclear warheads seen nuclear test projectile munition bullet fired downrange may may explosive device


traditionally projectiles classified shot shell former solid latter form payload shells also divided three configurations bursting base ejection nose ejection latter sometimes called shrapnel configuration modern base ejection introduced world war base nose ejection almost always used airburst fuzes bursting shells use various types fuze depending nature payload tactical need time payloads included '''bursting''' high explosive white phosphorus wp willie pete


wilson picket coloured marker chemical nuclear devices high explosive anti tank heat canister may considered special types bursting shell '''nose ejection''' shrapnel star incendiary flechette modern version shrapnel '''base ejection''' dual purpose improved conventional munition dpicm bomblets arm function set number rotations ejected projectile produces unexploded sub munitions duds remain dangerous scatterable mines illuminating coloured flare smoke incendiary propaganda chaff foil jam radars modern exotics electronic payloads sensor fuzed munitions stabilization '''rifled''' traditionally artillery projectiles spin stabilised meaning


spin flight gyroscopic forces prevent tumbling spin induced gun barrels rifling engages soft metal band around projectile called driving band uk rotating band us driving band usually made copper synthetic materials also used '''smoothbore fin stabilized''' modern artillery smoothbore tubes used mostly mortars projectiles use fins airflow rear maintain correct orientation primary benefits rifled barrels reduced barrel wear longer ranges achieved due reduced loss


energy friction gas escaping around projectile via rifling larger explosive cores given caliber artillery due less metal needing used form case projectile less force applied shell non rifled sides barrel smooth bore guns '''rifled fin stabilized''' combination used barrel rifled projectile also deployable fins stabilization guidance gliding propellant mm howitzer iran iraq war forms artillery require propellant propel


projectile target propellant always low explosive means deflagrates instead detonating high explosives shell accelerated high velocity short time rapid generation gas burning propellant high pressure achieved burning propellant contained area either chamber gun barrel combustion chamber rocket motor late th century available propellant black powder black powder many disadvantages propellant relatively low power requiring large


stable propellant many formulations developed following decades generally trying find optimum characteristics good artillery propellant low temperature high energy non corrosive highly stable cheap easy manufacture large quantities broadly modern gun propellants divided three classes single base propellants mainly entirely nitrocellulose based double base propellants composed combination nitrocellulose nitroglycerin triple base composed combination nitrocellulose nitroglycerin nitroguanidine artillery shells fired barrel assisted greater range three ways rocket assisted projectiles rap enhance sustain


metal cartridge cases generally anti aircraft artillery smaller caliber nbsp mm guns use metal cartridge cases include round propellant similar modern rifle cartridge simplifies loading necessary high rates fire bagged propellant allows amount powder raised lowered depending range target also makes handling larger shells easier requires totally different type breech metal case holds integral primer initiate propellant provides gas seal prevent


gases leaking breech called obturation bagged charges breech provides obturation holds primer either case primer usually percussion electrical also used laser ignition emerging modern nbsp mm guns primer magazine fitted breech battleship artillery ammunition four classifications according use '''service ''' ammunition used live fire training wartime use combat zone also known warshot ammunition '''practice ''' ammunition non minimally explosive projectile mimics characteristics range accuracy live rounds use


training conditions practice artillery ammunition often utilizes colored smoke generating bursting charge marking purposes place normal high explosive charge '''dummy ''' ammunition inert warhead inert primer propellant used training display '''blank ''' ammunition live primer greatly reduced propellant charge typically black powder projectile used training demonstration ceremonial use field artillery system ''cyclone'' th french artillery hoogstade belgium september modern field artillery mostly uses indirect fire guns part system enables attack targets invisible


accordance combined arms plan main functions field artillery system communications command authority allocate resources target acquisition detect identify deduce location targets control authority decide targets attack allot fire units attack computation firing data deliver fire fire unit onto target fire units guns launchers mortars grouped together specialist services produce data support production accurate firing data logistic services provide combat supplies particularly ammunition equipment support calculations produce


quadrant elevation range azimuth done manually using instruments tabulated data moment approximations battlefield computers started appearing early calculators copied manual method typically substituting polynomials tabulated data computers use different approach simulate shell 's trajectory 'flying' short steps applying data conditions affecting trajectory step simulation repeated produces quadrant elevation azimuth lands shell within required 'closing' distance target coordinates nato standard ballistic


model computer calculations expanded scope nato armaments ballistic kernel nabk within sg shareable fire control software suite logistics supply artillery ammunition always major component military logistics world war armies made artillery responsible forward ammunition supply load small arms ammunition trivial compared artillery different armies use different approaches ammunition supply vary nature operations differences include logistic service transfers artillery ammunition artillery amount ammunition carried


units extent stocks held unit battery level key difference whether supply 'push' 'pull' former 'pipeline' keeps pushing ammunition formations units defined rate latter units fire tactically necessary replenish maintain reach authorised holding vary logistic system able cope surge slack classification artillery finnish defence forces using mm gun direct fire mission live fire exercise artillery types


categorised several ways example type size weapon ordnance role organizational arrangements types ordnance types cannon artillery generally distinguished velocity fire projectiles types artillery german army pzh self propelled artillery heavy artillery large caliber guns capable firing long distance bombard target see also large calibre artillery field artillery mobile weapons used support armies field subcategories include infantry support guns directly support infantry units mountain guns lightweight guns moved difficult terrain field


guns capable long range direct fires howitzers capable high angle fire often employed indirect fires gun howitzers capable high low angle fire long barrel mortars typically short barreled high trajectory weapons designed primarily indirect fire role gun mortars breechloading mortars capable high low angle fire tank guns large caliber guns mounted tanks assault guns provide mobile direct fires anti tank artillery guns usually mobile designed primarily direct fire destroying armored fighting vehicles heavy armor anti aircraft artillery guns usually mobile designed attacking aircraft ground guns suitable


dual role anti aircraft anti tank warfare rocket artillery launches rockets instead shot shell railway gun large caliber weapons mounted transported fired specially designed railway wagonsnaval cannon early th century naval artillery guns mounted warships used either vessels bombard coastal targets support ground forces crowning achievement naval artillery battleship advent airpower missiles rendered type artillery largely obsolete typically longer barreled low trajectory high velocity weapons designed primarily direct fire role coastal artillery fixed position


weapons dedicated defense particular location usually coast example atlantic wall world war ii harbor needing mobile coastal artillery used much larger equivalent field artillery pieces giving longer range destructive power modern coastal artillery example russia 's bereg system often self propelled allowing avoid counter battery fire fully integrated meaning battery support systems requires maintenance targeting radar etc organic unit aircraft artillery large caliber guns mounted attack aircraft typically slow flying gunships nuclear


artillery artillery nuclear weapons modern field artillery also split two subcategories towed self propelled name suggests towed artillery prime mover usually artillery tractor truck move piece crew ammunition around towed artillery cases equipped apu small displacements self propelled artillery permanently mounted carriage vehicle room crew ammunition thus capable moving quickly one firing position another support fluid nature modern combat avoid counter battery fire


horse artillery first formed regular units late th century role supporting cavalry distinguished entire crew mounted field foot artillery main artillery arm field army using either guns howitzers mortars world war ii branch started using rockets later surface surface missiles fortress garrison artillery operated nation 's fixed defences using guns howitzers mortars either land coastal frontiers deployable elements provide heavy artillery field army nations coast defence artillery


naval responsibility mountain artillery nations treated mountain artillery separate branch others speciality another artillery branch used light guns howitzers usually designed pack animal transport easily broken small easily handled loads naval artillery nations carried pack artillery warships used manhandled naval marine landing parties times part ship 's armament would unshipped mated makeshift carriages limbers actions ashore example second boer war first world war


guns stricken sms ''k nigsberg'' formed main artillery strength german forces east africa firing pound gun louis philippe crepin world war many nations merged different artillery branches cases keeping sub branches naval artillery disappeared apart belonging marines however two new branches artillery emerged war aftermath used specialised guns rockets used direct indirect fire started make extensive use missiles anti tank artillery also various organisational


arrangements typically either field artillery specialist branch additional elements integral infantry etc units however armies field anti aircraft artillery also least secondary anti tank role world war ii anti tank western armies became mostly responsibility infantry armoured branches ceased artillery matter exceptions anti aircraft artillery various organisational arrangements including part artillery separate corps even separate service split army field airforce home defence cases infantry new armoured


corps also operated integral light anti aircraft artillery home defence anti aircraft artillery often used fixed well mobile mountings anti aircraft guns could also used field anti tank artillery providing suitable sights however general switch artillery indirect fire world war led reaction armies result accompanying infantry guns usually small short range guns could easily man handled used mostly direct fire could use indirect fire operated artillery branch


command supported unit world war ii joined self propelled assault guns although armies adopted infantry close support tanks armoured branch units purpose subsequently tanks generally took accompanying role equipment types three main types artillery gun guns howitzers mortars th century guns howitzers steadily merged artillery use making distinction terms somewhat meaningless end th century true guns calibers larger nbsp mm become rare artillery use main


howitzers higher velocities longer barrels equivalent guns first half th century true guns characterized long range maximum elevation significantly less high muzzle velocity hence relatively long barrel smooth bore rifling single charge latter often led fixed ammunition projectile locked cartridge case generally accepted minimum muzzle velocity barrel length associated gun adj gun full recoil action battle gallipoli photo ernest brooks


termed gun howitzers term first used howitzers relatively high maximum muzzle velocities introduced never became widely accepted armies electing widen definition gun howitzer equipments maximum elevations multi charge quite high maximum muzzle velocities relatively long barrels mortars simpler modern mortar originated world war several patterns war mortars settled stokes pattern characterized short barrel smooth bore low muzzle velocity


elevation angle firing generally greater simple light mounting using baseplate ground projectile integral propelling charge dropped barrel muzzle hit fixed firing pin since time mortars become rifled adopted breech loading recognized typifying characteristics artillery one characteristic type obturation used seal chamber prevent gases escaping breech may use metal cartridge case also holds propelling charge configuration called qf


quickfiring nations alternative use metal cartridge case propellant merely bagged combustible cases breech providing sealing called bl breech loading nations second characteristic form propulsion modern equipment either towed self propelled sp towed gun fires ground inherent protection limited gun shield towing horse teams lasted throughout world war ii armies others fully mechanized wheeled tracked gun towing vehicles


glider time first airborne trials ussr sp equipment gun integral part vehicle carries sps first appeared world war really develop world war ii mostly tracked vehicles wheeled sps started appear sps armor carry weapons ammunition armoured sps usually carry useful ammunition load early armoured sps mostly casemate configuration essence open top armored box offering


limited traverse however modern armored sps full enclosed armored turret usually giving full traverse gun many sps cannot fire without deploying stabilizers spades sometimes hydraulic sps designed recoil forces gun transferred directly onto ground baseplate towed guns given limited self propulsion means auxiliary engine two forms tactical propulsion used first half th century railways transporting equipment road two three separate loads disassembly


assembly beginning end journey railway artillery took two forms railway mountings heavy super heavy guns howitzers armored trains fighting vehicles armed light artillery direct fire role disassembled transport also used heavy super heavy weapons lasted caliber categories third form artillery typing classify light medium heavy various terms appears introduced world war spawned wide array artillery sorts sizes simple


categorical system needed armies defined categories bands calibers different bands used different types weapons field guns mortars anti aircraft guns coastal guns modern operations two french army giat gct mm nbsp mm auf self propelled guns th regiment d' artillerie ifor markings parked hekon base near mostar bosnia herzegovina support operation joint endeavor list countries order amount artillery russia north korea china india south korea united states turkey


israel egypt pakistan ref name hackett james p hackett james ed ''the military balance '' international institute strategic studies p ref syria ref name hackett james p iran ref name hackett james p algeria ref name hackett james p jordan ref name hackett james p iraq ref name hackett james p finland ref name hs ref brazil ref name hackett james p cameroon ref name hackett james p


morocco ref name hackett james p hungary france ref name hackett james p artillery used variety roles depending type caliber general role artillery provide ''fire support'' application fire coordinated manoeuvre forces destroy ''neutralize'' ' 'suppress'' enemy nato definition makes artillery supporting arm although nato armies agree logic ''italicised'' terms nato 's unlike rockets guns howitzers armies still call mortars suitable


armies armor units means generally ''concentrate'' fire shorter range disadvantage armies also consider infantry operated mortars responsive artillery function control arrangements case armies however mortars always used artillery units remain many armies including nato nato armies artillery usually assigned tactical mission establishes relationship responsibilities formation units assigned


seems nato nations use terms outside nato others probably used standard terms ' 'direct support'' ''general support'' ''general support reinforcing'' ' 'reinforcing'' tactical missions context command authority ''operational command'' ''operational control'' ''tactical command'' ''tactical control'' nato direct support generally means directly supporting artillery unit provides observers liaison manoeuvre troops supported typically artillery battalion equivalent assigned brigade batteries brigade 's battalions however armies achieve placing assigned artillery


''unobserved'' former may ''adjusted'' latter ''predicted'' observation adjusted fire may directly forward observer indirectly via ''target acquisition'' system nato also recognises several different types fire support tactical purposes ''counterbattery fire'' delivered purpose destroying ''neutralizing'' enemy 's fire support system ''counterpreparation fire'' intensive prearranged fire delivered imminence enemy attack discovered ''covering fire'' used protect troops within range enemy small arms ''defensive fire'' delivered supporting units


serious threat supported unit usmc firing outside fallujah iraq two nato terms also need definition ''neutralization fire'' delivered render target temporarily ineffective unusable ''suppression fire'' degrades performance target level needed fulfill mission suppression usually effective duration fire tactical purposes also include various mission verbs rapidly expanding subject modern concept effects based operations ''targeting'' process selecting target matching appropriate response taking account operational


requirements capabilities requires consideration type fire support required extent coordination supported arm involves decisions effects required example ''neutralization'' ' 'suppression'' proximity risks troops non combatants types munitions including fuzing used quantities targets attacked possibly long methods used example ''converged'' ' 'distributed'' whether adjustment permissible surprise essential need special procedures precision danger close


many fire units needed ones available range required munitions type quantity allotted another target suitable line fire risk troops non combatants ''targeting'' process key aspect tactical fire control depending circumstances national procedures may undertaken one place may distributed armies practicing control front process may undertaken forward observer target acquirer


particularly case smaller target requiring fire units extent process formal informal makes use computer based systems documented norms experience judgement also varies widely armies circumstances surprise may essential irrelevant depends effects required whether target likely move quickly improve protective posture world war ii uk researchers concluded impact fuzed munitions relative risk follows men standing men lying men


firing trenches men crouching trenches airburst munitions significantly increase relative risk lying men etc historically casualties occur first seconds fire ie time needed react improve protective posture however less relevant airburst used several ways making best use brief window maximum vulnerability ordering guns fire together either executive order fire time disadvantage fire ''concentrated'' many dispersed ''fire units''


different times flight first rounds spread time extent large concentration offsets problem may mean one round required gun could arrive second window burst fire rate fire deliver three rounds gun within seconds reduces number guns hence fire units needed means may less dispersed less variation times flight smaller caliber guns nbsp mm always


able deliver three rounds seconds larger calibers firing fixed rounds could also n't multi charge nbsp mm howitzer fh first gained capability multiple round simultaneous impact mrsi single weapon multiple individual weapons fire multiple rounds differing trajectories rounds arrive target time ''time target'' fire units fire time less time flight works well prearranged scheduled fire less satisfactory opportunity targets means delaying delivery fire


selecting 'safe' time fire units achieve used previous two methods counter battery fire modern counter battery fire developed world war objective defeating enemy 's artillery typically fire used suppress enemy batteries interfere activities friendly forces prevent enemy defensive artillery fire impending attack systematically destroy enemy guns world war latter required air observation first indirect counter battery fire may


observer balloon enemy artillery detected two ways either direct observation guns air ground observers including specialist reconnaissance firing signatures includes radars tracking shells flight determine place origin sound ranging detecting guns firing resecting position pairs microphones cross observation gun flashes using observation human observers opto electronic devices although widespread adoption 'flashless' propellant limited effectiveness latter hostile batteries detected may engaged immediately


aircraft 'follow' battery moves defensive measures batteries include frequently changing position constructing defensive earthworks tunnels used north korea extreme example counter measures include air defence aircraft attacking counter battery radars physically electronically modern artillery ammunition caliber nbsp mm used pzh field artillery team 'field artillery team' us term following description terminology applies us armies broadly similar differ significant details modern field artillery post world war three distinct parts forward observer fo fire


direction center fdc actual guns forward observer observes target using tools binoculars laser rangefinders designators call back fire missions radio relays data portable computer via encrypted digital radio connection protected jamming computerized frequency hopping lesser known part team fas field artillery survey team sets gun line cannons today artillery battalions use n aiming circle allows faster setup mobility fas teams still used checks


balances purposes gun battery issues aiming circle fas team fo communicate directly battery fdc one per battery guns otherwise several fos communicate higher fdc battalion level higher fdc prioritizes targets allocates fires individual batteries needed engage targets spotted fos perform preplanned fires battery fdc computes firing data ammunition used powder charge fuse settings


direction target quadrant elevation fired reach target gun fire rounds needed adjusting target number rounds fired target gun target accurately located guns traditionally data relayed via radio wire communications warning order guns followed orders specifying type ammunition fuse setting direction elevation needed reach target method adjustment orders fire effect ffe


however advanced artillery units data relayed digital radio link parts field artillery team include meteorological analysis determine temperature humidity pressure air wind direction speed different altitudes also radar used determining location enemy artillery mortar batteries determine precise actual strike points rounds fired battery comparing location expected compute registration allowing future rounds fired much greater accuracy time target technique


computer engaging fire unit subtracts time flight tot determine time fire executive order fire given guns fire unit correct moment fire fire unit fires rounds individual firing time opening rounds reach target area almost simultaneously especially effective combined techniques allow fires effect made without preliminary adjusting fires multiple rounds simultaneous impact mrsi illustration different trajectories used mrsi muzzle


target typically one degrees horizontal using different size propelling charges shell possible create multiple trajectories higher trajectories cause shells arc higher air take longer reach target shells fired trajectories first volleys starting shell propellant working correct pause volleys fired lower trajectories shells arrive time


useful many shells land target warning traditional volleys along trajectory anybody target area may time however long takes reload fire guns take cover volleys however guns capable burst fire deliver several rounds seconds use firing data guns one location firing one target use time target procedures shells arrive time target


engage targets using mrsi requires two things firstly guns requisite rate fire sufficiently different size propelling charges secondly fire control computer designed compute missions data handling capability allows firing data produced sent gun presented gun commander correct order number rounds delivered mrsi depends primarily range target rate fire maximum rounds range limited lowest propelling charge


reach target examples guns rate fire makes suitable mrsi includes uk 's south africa 's denel g land six rounds simultaneously targets least away germany 's panzerhaubitze land five rounds simultaneously targets least away slovakia 's nbsp mm spgh zuzana model k thunder archer project developed bae systems bofors sweden nbsp mm howitzer wheeled chassis claimed able deliver six shells target simultaneously gun nbsp mm twin


barrel amos mortar system joint developed h gglunds sweden patria finland capable shells mrsi united states crusader program cancelled slated mrsi capability unclear many fire control computers necessary capabilities two round mrsi firings popular artillery demonstration well trained detachments could show skills spectators air burst destructiveness artillery bombardments enhanced shells set airburst meaning explode air target instead


upon impact accomplished either time fuzes proximity fuzes time fuzes use precise timer detonate shell preset delay technique tricky slight variations functioning fuze cause explode high ineffective strike ground instead exploding since december battle bulge proximity fuzed artillery shells available take guesswork process employ miniature low powered radar transmitter fuze detect ground explode


predetermined height return weak radar signal completes electrical circuit fuze explodes shell proximity fuze developed british increase effectiveness anti aircraft warfare effective tactic infantry light vehicles scatters fragmentation shell larger area prevents blocked terrain entrenchments include form robust overhead cover combined tot mrsi tactics give warning incoming rounds rounds


especially devastating many enemy soldiers likely caught open even attack launched assembly area troops moving open rather unit entrenched tactical position use monuments artillery piece monument commemorating battle tupelo american civil war numerous war memorials around world incorporate artillery piece used specific war battle commemorated see also list artillery indirect fire advanced gun system aiming point artillery battery artillery fuze artillery museums


barrage artillery beehive anti personnel round combustion light gas gun cordite counter battery fire counter battery radar fuze project babylon gun laying howitzer light gas gun naval artillery nuclear artillery paris gun railgun coilgun shell projectile shoot scoot shrapnel shell sound ranging suppressive fire references notes bibliography tm reading external links http wwwpafgcouk portsmouth action field gun pictures video http wwwnavweapscom weapons index weaponshtm naval weapons world http wwwcannonartillerycom cannon artillery voice freedom 's thunder http wwwenemyforcescom artilleryhtm modern artillery https wwwtandfonlinecom doi pdf z needaccess true sort forensic information derived analysis shell fragments evans nigel f http nigeleftripodcom indexhtm british artillery world war http napoleonistykaatspacecom artillery tacticshtm


artillery tactics combat napoleonic wars http napoleonistykaatspacecom imperial guard artilleryhtm artillery napoleon 's imperial guard http wwwartillerieinfo french artillery ammunition th end th century historic films showing artillery world war http wwweuropeanfilmgatewayeu node efg artillery multilingual showonly video europeanfilmgatewayeu https wwwyoutubecom watchv iuvcdkgd fm video inside shrieking shrapnel hear great sound shrapnel 's finnish field artillery fire video year chinese inventions explosive weapons


'''administrative law''' division law governs activities executive branch agencies government administrative law concerns executive branch rule making executive branch rules generally referred regulations adjudication enforcement laws administrative law considered branch public law administrative law deals decision making administrative units government part executive branch areas international trade manufacturing environment taxation broadcasting immigration transport administrative law expanded greatly twentieth century legislative bodies worldwide created government agencies


public treasury divisions state courts matters concerning states constitutional reform led government president fernando henrique cardoso introduced regulatory agencies part executive branch since brazilian administrative law strongly influenced judicial interpretations constitutional principles public administration art federal constitution legality impersonality publicity administrative acts morality efficiency chile chile president republic exercises administrative function collaboration several ministries authorities ''ministerial rank'' ministry one


secretary performs public services actual satisfaction public needs single specialized court deal actions administrative entities instead several specialized courts procedures review china prc administrative law people 's republic china virtually non existent economic reform era initiated deng xiaoping since people 's republic china constructed new legal framework administrative law establishing control mechanisms overseeing bureaucracy disciplinary committees communist party china however many argued


usefulness laws vastly inadequate terms controlling government actions largely institutional systemic obstacles like weak judiciary poorly trained judges lawyers corruption administrative supervision regulations administrative reconsideration regulations passed state civil servant provisional regulations changed way government officials selected promoted requiring pass exams yearly appraisals introduced rotation system three regulations amended upgraded laws state compensation law passed followed administrative penalties


law administrative compulsory law enforced administrative litigation law amended general administrative procedure law way france france claims national local governments well claims private bodies providing public services handled administrative courts use ''conseil d' tat'' council state court last resort ordinary special courts main administrative courts ''tribunaux administratifs'' appeal courts ''cours administratives d'appel'' special administrative courts include national court asylum


service users '' galit devant le service public'' equal access government employment '' galit d'acc la fonction publique'' without regard political opinions freedom association ''libert d'association'' right entrepreneurship ''libert du commerce et de l'industrie'' lit freedom commerce industry right legal certainty ''droit la curit juridique'' french administrative law founder continental administrative law strong influence administrative laws several countries belgium greece turkey tunisia germany germany administrative law called '''verwaltungsrecht''' generally rules relationship authorities


citizens establishes citizens' rights obligations authorities part public law deals organization tasks acting public administration also contains rules regulations orders decisions created related administrative agencies federal agencies federal state authorities urban administrations also admission offices fiscal authorities etc administrative law germany follows three basic principles principle legality authority means acting law acting without law principle


legal security includes principle legal certainty principle non retroactivity principle proportionality means act authority suitable necessary appropriate administrative law germany divided '''general administrative law''' '' 'special administrative law''' general administrative law general administration law basically ruled administrative procedures law ''verwaltungsverfahrensgesetz'' vwvfg legal sources rules administrative courts verwaltungsgerichtsordnung vwgo social security code sozialgesetzbuch sgb general fiscal law abgabenordnung ao administrative procedures law ''verwaltungsverfahrensgesetz'' vwvfg


citizen definition says administration act characterized following features official act authority field public law resolve individual case effect outside vwv fg rule structure necessary elements administrative act vwvfg high relevance practice well paragraphs prerequisites redemption unlawful administration act vwvfg withdrawal


lawful administration act vwvfg listed legal sources administration procedural law verwaltungsgerichtsordnung vwgo enacted rules court procedures administrative court vwgo divided five parts constitution courts action remedies retrial costs enforcement final clauses temporary arrangements absence rule vwgo supplemented code civil procedure zivilprozessordnung zpo judicature act gerichtsverfassungsgesetz gvg addition regulation administrative procedure vwvfg also constitutes legal protection administrative


law beyond court procedure vwvgo rules preliminary proceeding called vorverfahren widerspruchsverfahren stringent prerequisite administrative procedure action rescission writ mandamus authority aimed preliminary proceeding gives citizen feeling unlawfully mistreated authority possibility object force review administrative act without going court prerequisites open public law remedy listed vwgo therefore necessary existence conflict public law without


constitutional aspects assignment another jurisdiction social security code sozialgesetzbuch sgb general fiscal law less important administrative law supplement vwvfg vwgo fields taxation social legislation social welfare financial support students baf g etc special administrative law special administrative law consists various laws special sector law important ones town country planning code baugesetzbuch baugb federal control pollution act bundesimmissionsschutzgesetz bimschg industrial code gewerbeordnung gewo police law polizei


und ordnungsrecht statute governing restaurants gastst ttenrecht gastg germany highest administrative court matters federal administrative court bundesverwaltungsgericht federal courts special jurisdiction fields social security law bundessozialgericht tax law bundesfinanzhof italy italy administrative law known '''diritto amministrativo'' branch public law whose rules govern organization public administration activities pursuit public interest public administration relationship citizens genesis related principle division powers


state administrative power originally called executive organize resources people whose function devolved achieve public interest objectives defined law netherlands netherlands administrative law provisions usually contained various laws public services regulations however also single general administrative law act algemene wet bestuursrecht awb rather good sample procedural laws europe applies making administrative decisions judicial review decisions courts another act judicial procedures


administrative chamber specializes administrative appeals courts appeal administrative cases however specialized depending case administrative appeals end judicial section council state raad van state sweden stenbockska palace former seat supreme administrative court sweden sweden system administrative courts considers administrative law cases completely separate system general courts system three tiers county administrative courts ''f rvaltningsr tt'' first tier four administrative courts


appeal ''kammarr tt'' second tier supreme administrative court sweden ''h gsta f rvaltningsdomstolen'' third tier migration cases handled two tier system effectively within system general administrative courts three administrative courts serve migration courts ''migrationsdomstol'' administrative court appeal stockholm serving migration court appeal ''migrations verdomstolen'' taiwan roc taiwan recently enacted ''constitutional procedure act'' former ''constitutional interpretation procedure act '' '''justices constitutional court''' judicial yuan taiwan charge judicial interpretation council made


interpretations date turkey turkey lawsuits acts actions national local governments public bodies handled administrative courts main administrative courts decisions administrative courts checked regional administrative courts council state council state court last resort exactly similar conseil d' tat france ukraine administrative law ukraine homogeneous legal substance isolated system jurisprudence characterized branch law science


review may limited certain questions fairness whether administrative action ''ultra vires'' terms ultra vires actions broad sense reviewing court may set aside administrative decision unreasonable canadian law following rejection patently unreasonable standard supreme court dunsmuir v new brunswick ''wednesbury'' unreasonable british law arbitrary capricious us administrative procedure act new york state law administrative law laid supreme court india also recognized two grounds judicial review


recognized applied english courts namely legitimate expectation proportionality powers review administrative decisions usually established statute originally developed royal prerogative writs english law writ mandamus writ certiorari certain common law jurisdictions india pakistan power pass writs constitutionally guaranteed power power seen fundamental power judicial review aspect independent judiciary australia canada singapore united kingdom


united states american administrative law often involves regulatory activities called independent agencies federal trade commission whose headquarters shown united states many government agencies organized executive branch government although part judicial legislative branches federal government executive branch led president controls federal executive departments led secretaries members united states cabinet many independent agencies united states government created statutes enacted congress exist outside


code federal regulations adjudicate administrative hearings execute administrative goals agency enforcement personnel united states constitution sets limits tripartite authority administrative agencies congress enacted apa establish fair administrative law procedures comply constitutional requirements due process agency procedures drawn four sources authority apa organic statutes agency rules informal agency practice important note though agencies act within congressionally delegated authority must comply requirements apa state level


first version model state administrative procedure act promulgated published uniform law commission ulc year federal administrative procedure act drafted incorporated basic principles enough elaboration detail support essential features therefore model uniform act model act needed state administrative law states uniform variety approaches used various states later modified present version model state administrative


procedure act '''msapa''' maintains continuity earlier ones reason revision past two decades state legislatures dissatisfied agency rule making adjudication enacted statutes modify administrative adjudication rule making procedure american bar association 's official journal concerning administrative law ''administrative law review'' quarterly publication managed edited students washington college law historical development stephen breyer us supreme court justice since divides history administrative law united states six discrete periods book


''administrative law regulatory policy'' ed english antecedents american experience rise regulation traditional model administrative law new deal administrative procedure act maturation traditional model administrative law critique transformation administrative process retreat consolidation agriculture agricultural sector one heavily regulated sectors us economy regulated various ways international federal state


local levels consequently administrative law significant component discipline agricultural law united states department agriculture myriad agencies http wwwamsusdagov agricultural marketing service primary sources regulatory activity although administrative bodies environmental protection agency play significant regulatory role well see also constitutionalism rule law rechtsstaat references reading


'''accounting''' also known '''accountancy''' measurement processing communication financial non financial information economic entities ref name np ref businesses corporations accounting called language business ref name wharton language ref measures results organization 's economic activities conveys information variety users including investors creditors management regulators ref name uw dept ref practitioners accounting known accountants terms accounting financial reporting often used synonyms accounting divided several fields including financial accounting management accounting tax accounting


cost accounting ref name wc accounting information systems designed support accounting functions related activities financial accounting focuses reporting organization 's financial information including preparation financial statements external users information investors regulators suppliers ref name hdf management accounting focuses measurement analysis reporting information internal use management ref name np ref name hdf recording financial transactions summaries financials may presented financial reports known


bookkeeping double entry bookkeeping common system ref name l ref accounting existed various forms levels sophistication throughout human history double entry accounting system use today developed medieval europe particularly venice usually attributed italian mathematician franciscan friar luca pacioli ref name jkdiwan ref today accounting facilitated accounting organizations standard setters accounting firms professional bodies financial statements usually audited accounting firms ref name parliament auditors prepared accordance generally accepted accounting principles gaap ref name hdf


gaap set various standard setting organizations financial accounting standards board fasb united states ref name np financial reporting council united kingdom major economies plans converge towards adopt international financial reporting standards ifrs ref name globalcon ifrs foundation http wwwifrsorg use around world use around worldhtmwbcmode presentationunpublished move towards global standards retrieved april ref history ''portrait luca pacioli'' painted jacopo de' barbari museo di capodimonte accounting thousands years old traced ancient civilizations ref name r robson keith


accounting numbers inscription action distance development accounting ''accounting organizations society'' ref ref name nysscpa ref ref name unisa ref early development accounting dates back ancient mesopotamia closely related developments writing counting money ref name r also evidence early forms bookkeeping ancient iran ref name g ref ref name od oldroyd david dobie alisdair ''themes history bookkeeping'' routledge companion accounting history london july chapter p ref early auditing systems


turn related vulgar latin word ''computare'' meaning reckon base ''computare'' ''putare'' variously meant prune purify correct account hence count calculate well think ref name b word accountant derived french word also derived italian latin word word formerly written english accomptant process time word always pronounced dropping p became gradually changed pronunciation orthography present form


terminology '''accounting''' variously defined keeping preparation financial records transactions firm analysis verification reporting records principles procedures accounting also refers job accountant ref name cambridge business accounting ref ref name cambridge british accounting ref ref name mw accounting ref '''accountancy''' refers occupation profession accountant ref name mw accountancy ref ref name cambridge business accountancy ref ref name cambridge british accountancy ref particularly british english ref name cambridge business accounting ref name cambridge


auditing auditing verification assertions made others regarding payoff ref name b baiman stanley discussion auditing incentives truthful reporting journal accounting research ref context accounting unbiased examination evaluation financial statements organization ref name ref audit professional service systematic conventional audit financial statements aims express disclaim independent opinion financial statements auditor expresses independent opinion fairness financial statements presents


financial position results operations cash flows entity accordance generally acceptable accounting principles gaap material respects auditor also required identify circumstances generally acceptable accounting principles gaap consistently observed ref name sas responsibilities ref information systems accounting information system part organization 's information system used processing accounting data ref name openlearn ref many corporations use artificial intelligence based information systems banking finance industry uses ai fraud detection retail industry uses ai customer services ai also


used cybersecurity industry involves computer hardware software systems using statistics modeling many accounting practices simplified help accounting computer based software enterprise resource planning erp system commonly used large organisation provides comprehensive centralized integrated source information companies use manage major business processes purchasing manufacturing human resources systems cloud based available demand via application browser available software installed specific computers local servers often referred premise tax


accounting tax accounting united states concentrates preparation analysis presentation tax payments tax returns us tax system requires use specialised accounting principles tax purposes differ generally accepted accounting principles gaap financial reporting ref name autogenerated ref us tax law covers four basic forms business ownership sole proprietorship partnership corporation limited liability company corporate personal income taxed different rates varying according income levels including varying marginal rates taxed additional dollar income average rates set


percentage overall income ref name autogenerated forensic accounting forensic accounting specialty practice area accounting describes engagements result actual anticipated disputes litigation forensic means suitable use court law standard potential outcome forensic accountants generally work political campaign accounting political campaign accounting deals development implementation financial systems accounting financial transactions compliance laws governing political campaign operations branch accounting first formally introduced march issue ''the


journal accountancy'' organizations professional bodies professional accounting bodies include american institute certified public accountants aicpa members international federation accountants ifac ref name ifac ref including institute chartered accountants scotland icas institute chartered accountants pakistan icap cpa australia institute chartered accountants india association chartered certified accountants acca institute chartered accountants england wales icaew professional bodies subfields accounting professions also exist example chartered institute management accountants cima uk institute management


large international accounting firms mid twentieth century large mergers late twentieth century led dominance auditing market big five accounting firms arthur andersen deloitte ernst young kpmg pricewaterhousecoopers ref name parliament auditors ref demise arthur andersen following enron scandal reduced big five big four ref name ft big four ref standard setters generally accepted accounting principles gaap accounting standards issued national regulatory bodies addition international accounting standards board iasb issues international financial reporting standards ifrs implemented


countries ref name np standards international audit assurance ethics education public sector accounting set independent standard settings boards supported ifac international auditing assurance standards board sets international standards auditing assurance quality control international ethics standards board accountants iesba ref name ifac ref sets internationally appropriate principles based ''code ethics professional accountants'' international accounting education standards board iaesb sets professional accounting education standards ref name ifac ref international public sector accounting standards board ipsasb sets accrual based international public sector accounting standards ref name ifac ref organizations individual countries


may issue accounting standards unique countries example united states financial accounting standards board fasb issues statements financial accounting standards form basis us gaap ref name np united kingdom financial reporting council frc sets accounting standards ref name icaew standards ref however major economies plans converge towards adopt ifrs ref name globalcon education training qualifications degrees least bachelor 's degree accounting related field required accountant auditor job


positions employers prefer applicants master 's degree ref name bls ref degree accounting may also required may used fulfill requirements membership professional accounting bodies example education accounting degree used fulfill american institute cpa 's aicpa semester hour requirement ref name aicpa ref associate membership certified public accountants association uk available gaining degree finance accounting ref name acpa criteria ref doctorate required order pursue career accounting


academia example work university professor accounting ref name aicpa academia ref ref name byu prep ref doctor philosophy phd doctor business administration dba popular degrees phd common degree wishing pursue career academia dba programs generally focus equipping business executives business public careers requiring research skills qualifications ref name aicpa academia professional qualifications professional accounting qualifications include chartered accountant designations qualifications including certificates diplomas ref name acca qualifications ref scotland chartered


accountants icas undergo continuous professional development abide icas code ethics england wales chartered accountants icaew undergo annual training bound icaew 's code ethics subject disciplinary procedures ref name icaew chartered ref united states requirements joining aicpa certified public accountant set board accountancy state members agree abide aicpa 's code professional conduct bylaws acca largest global accountancy body members organisation provides


research carried academic researchers practicing accountants methodologies academic accounting research include archival research examines objective data collected repositories experimental research examines data researcher gathered administering treatments subjects analytical research based act formally modeling theories substantiating ideas mathematical terms interpretive research emphasizes role language interpretation understanding accounting practice highlighting symbolic structures taken granted themes pattern world distinct ways critical research emphasizes role power conflict accounting practice case studies


computer simulation field research ref name csww coyne joshua g scott l summers brady williams david wood accounting program research rankings topical area methodology ''issues accounting education'' november ref ref name chua ref empirical studies document leading accounting journals publish total fewer research articles comparable journals economics business disciplines ref name jae ref consequently accounting scholars relatively less successful academic publishing business school peers ref name car ref due different publication rates accounting business disciplines recent study based academic author rankings concludes


competitive value single publication top ranked journal highest accounting lowest marketing ref name jbr ref scandals year witnessed series financial information frauds involving enron auditing firm arthur andersen telecommunications company worldcom qwest sunbeam among well known corporations problems highlighted need review effectiveness accounting standards auditing regulations corporate governance principles cases management manipulated figures shown financial reports indicate better economic performance others tax regulatory incentives encouraged leveraging companies decisions bear extraordinary


unjustified risk ref name mbaufmedugt astrid ayala giancarlo ib rg en snr market proposal auditing financial statements public companies journal management value universidad francisco marroqu n march p https webarchiveorg web http wwwmbaufmedugt journalofmanagement content eng marketproposalpdf ufmedugt ref enron scandal deeply influenced development new regulations improve reliability financial reporting increased public awareness importance accounting standards show financial reality companies objectivity independence auditing firms ref name mbaufmedugt addition largest bankruptcy reorganization american history enron scandal undoubtedly biggest audit failure causing


fraud error accounting fraud intentional misstatement omission accounting records management employees involves use deception criminal act breach civil tort may involve collusion third parties ref name iaasb isa ref accounting error unintentional misstatement omission accounting records example misinterpretation facts mistakes processing data oversights leading incorrect estimates ref name iaasb isa ref acts leading accounting errors criminal may breach civil law example tort negligence primary responsibility prevention


detection fraud errors rests entity 's management ref name iaasb isa ref see also accounting information system accounting records references external links https wwwinformsorg informs history traditions application areas accounting operations research accounting institute operations research management sciences website financial accounting fi laskentatoimi


nucleic acids may biomolecules universe capable coding life processes ref name astrodna ref '''astrobiology''' formerly known '''exobiology''' interdisciplinary scientific field studies origins early evolution distribution future life universe astrobiology considers question whether extraterrestrial life exists humans detect ref name ref astrobiology makes use molecular biology biophysics biochemistry chemistry astronomy physical cosmology exoplanetology geology paleontology ichnology investigate possibility life worlds help recognize biospheres might different earth

Natural science
Space science
Astrobiology


origin early evolution life inseparable part discipline astrobiology astrobiology concerns interpretation existing scientific data although speculation entertained give context astrobiology concerns primarily hypotheses fit firmly existing scientific theories interdisciplinary field encompasses research origin planetary systems origins organic compounds space rock water carbon interactions abiogenesis earth planetary habitability research biosignatures life detection studies potential life adapt challenges earth outer space ref name goals ref ref name nyt jc ref biochemistry may begun shortly


big bang billion years ago habitable epoch universe million years old ref name ija october ref ref name nyt ref according panspermia hypothesis microscopic life distributed meteoroids asteroids small solar system bodies may exist throughout universe ref name usra ref ref name ref according research published august large galaxies may favorable creation development habitable planets smaller galaxies milky way ref name sp ref nonetheless earth place universe humans know harbor life ref name nasa ref ref name astrobiology ref estimates habitable zones around stars ref name nyt ref


sometimes referred goldilocks zones along discovery thousands extrasolar planets new insights extreme habitats earth suggest may many habitable places universe considered possible recently ref name nyt ref ref name pnas ref ref name latimes ref current studies planet mars ''curiosity'' ''perseverance'' rovers searching evidence ancient life well plains related ancient rivers lakes may habitable ref name sci ref ref name sci special ref ref name sci ref ref name sci c ref search evidence habitability taphonomy related fossils organic molecules planet mars


primary nasa esa objective even extraterrestrial life never discovered interdisciplinary nature astrobiology cosmic evolutionary perspectives engendered may still result range benefits earth overview term first proposed russian soviet astronomer gavriil tikhov ''astrobiology'' etymologically derived greek ''astron'' constellation star ''bios'' life '' logia'' ' 'study'' synonyms astrobiology diverse however synonyms structured relation important sciences implied development astronomy biology


close synonym ''exobiology'' greek external ''bios'' life logia ' 'study'' term exobiology coined molecular biologist nobel prize winner joshua lederberg exobiology considered narrow scope limited search life external earth whereas subject area astrobiology wider investigates link life universe includes search extraterrestrial life also includes study life earth origin evolution limits url status live ref chloroplasts within plant cells shown another term used past xenobiology


though considered outside mainstream scientific inquiry astrobiology become formalized field study planetary scientist david grinspoon calls astrobiology field natural philosophy grounding speculation unknown known scientific theory nasa 's interest exobiology first began development us space program nasa funded first exobiology project nasa founded exobiology program one four main elements nasa 's current astrobiology program ref name nasa funded search extraterrestrial intelligence seti search radio frequencies electromagnetic spectrum


interstellar communications transmitted extraterrestrial life outside solar system nasa 's viking missions mars launched included three biology experiments designed look metabolism present life mars june john w kluge center library congress held seminar focusing astrobiology panel members l r robin lovin derek malone france steven j dick advancements fields astrobiology observational astronomy discovery large varieties extremophiles extraordinary capability thrive harshest environments earth led speculation life may possibly


thriving many extraterrestrial bodies universe ref name particular focus current astrobiology research search life mars due planet 's proximity earth geological history growing body evidence suggest mars previously considerable amount water surface ref name lpiusraedu ref ref name heisinger ref water considered essential precursor development carbon based life ref name autogenerated ref missions specifically designed search current life mars viking program beagle probes viking results inconclusive beagle failed


minutes landing ref name bbc news jan ref future mission strong astrobiology role would jupiter icy moons orbiter designed study frozen moons jupiter may liquid water cancelled late phoenix lander probed environment past present planetary habitability microbial life mars researched history water european space agency 's astrobiology roadmap identified five main research topics specifies several key scientific objectives topic five research topics ref name esa astromap ref


origin evolution planetary systems origins organic compounds space rock water carbon interactions organic synthesis earth steps life life habitability biosignatures facilitating life detection november nasa launched mars science laboratory mission carrying ''curiosity'' rover landed mars gale crater august ref name gale crater ref ref name gale crater ref ref name gale crater ref ''curiosity'' rover currently probing environment past present planetary habitability microbial life mars december nasa reported based evidence ''curiosity'' studying aeolis palus gale crater


contained ancient freshwater lake could hospitable environment microbial life ref name nyt ref ref name sci european space agency currently collaborating russian federal space agency roscosmos developing exomars astrobiology rover scheduled launched july postponed ref name launchmoved ref meanwhile nasa launched mars astrobiology rover sample cacher later return earth methodology planetary habitability looking life planets like earth simplifying assumptions useful reduce size task astrobiologist one


informed assumption vast majority life forms galaxy based carbon chemistries life forms earth carbon well known unusually wide variety molecules formed around carbon fourth abundant element universe energy required make break bond appropriate level building molecules stable also reactive fact carbon atoms bond readily carbon atoms allows building extremely long complex molecules


presence liquid water assumed requirement common molecule provides excellent environment formation complicated carbon based molecules could eventually lead emergence life ref name ssr ref researchers posit environments water ammonia mixtures possible solvents hypothetical types biochemistry third assumption focus planets orbiting sun like stars increased probabilities planetary habitability large stars relatively short lifetimes meaning life might time emerge planets orbiting small stars provide little heat warmth


planets close orbits around would frozen solid close orbits planets would tidally locked star long lifetimes red dwarfs could allow development habitable environments planets thick atmospheres significant red dwarfs extremely common see habitability red dwarf systems since earth planet known harbor life evident way know simplifying assumptions correct communication attempts illustration pioneer plaque research communication extraterrestrial intelligence ceti focuses


artist 's impression extrasolar planet ogle blg lb orbiting star light years earth planet discovered gravitational microlensing nasa kepler mission launched march searches extrasolar planets astronomy related astrobiology research falls category extrasolar planet exoplanet detection hypothesis life arose earth could also arise planets similar characteristics end number instruments designed detect earth sized exoplanets considered notably nasa 's terrestrial planet finder tpf esa 's darwin programs cancelled nasa


launched ''kepler'' mission march french space agency launched corot space mission also several less ambitious ground based efforts underway goal missions detect earth sized planets also directly detect light planet may studied spectroscopically examining planetary spectra would possible determine basic composition extrasolar planet 's atmosphere surface given knowledge may possible assess likelihood life found planet nasa research group virtual


fraction planets life might arise math n r times f p times n e times f l times f times f c times l math '''''n''''' number communicative civilizations '''''r''''' rate formation suitable stars stars sun '''''f sub p sub ''''' fraction stars planets current evidence indicates planetary systems may common stars like sun '''''n sub e sub ''''' number earth sized worlds per planetary system '''''f sub l sub ''''' fraction earth sized planets life


actually develops '''''f sub sub ''''' fraction life sites intelligence develops '''''f sub c sub ''''' fraction communicative planets electromagnetic communications technology develops '''''l''''' lifetime communicating civilizations however whilst rationale behind equation sound unlikely equation constrained reasonable limits error time soon problem formula used generate support hypotheses contains factors never verified first term '''''r''''' number stars generally constrained within orders magnitude


second third terms ''f sub p sub '' stars planets ''f sub e sub '' planets habitable conditions evaluated star 's neighborhood drake originally formulated equation merely agenda discussion green bank conference applications formula taken literally related simplistic pseudoscientific arguments ref name bc ref another associated topic fermi paradox suggests intelligent life common universe obvious signs another active research area astrobiology planetary system formation suggested peculiarities


solar system example presence jupiter protective shield may greatly increased probability intelligent life arising planet biology hydrothermal vents able support extremophile bacteria earth may also support life parts cosmos biology cannot state process phenomenon mathematically possible exist forcibly extraterrestrial body biologists specify speculative ref name bc discovery extremophiles organisms able survive extreme environments became core research element astrobiologists important


understand four areas limits life planetary context potential panspermia forward contamination due human exploration ventures planetary colonization humans exploration extinct extant extraterrestrial life life thought entirely dependent energy sun plants earth 's surface capture energy sunlight photosynthesize sugars carbon dioxide water releasing oxygen process consumed oxygen respiring organisms passing energy food chain even life ocean depths sunlight cannot reach thought obtain


nourishment either consuming organic detritus rained surface waters eating animals ref name smoker ref world 's ability support life thought depend access sunlight however exploratory dive galapagos rift deep sea exploration submersible ''alvin'' scientists discovered colonies giant tube worms clams crustaceans mussels assorted creatures clustered around undersea volcanic features known black smokers ref name smoker creatures thrive despite access sunlight soon discovered comprise entirely independent ecosystem although


multicellular lifeforms need dissolved oxygen produced oxygenic photosynthesis aerobic cellular respiration thus completely independent sunlight basis food chain form bacterium derives energy oxidization reactive chemicals hydrogen hydrogen sulfide bubble earth 's interior lifeforms entirely decoupled energy sunlight green sulfur bacteria capturing geothermal light anoxygenic photosynthesis bacteria running chemolithoautotrophy based radioactive decay uranium ref name trixler ref chemosynthesis revolutionized study biology astrobiology


revealing life need sun dependent requires water energy gradient order exist biologists found extremophiles thrive ice boiling water acid alkali water core nuclear reactors salt crystals toxic waste range extreme habitats previously thought inhospitable life ref name cavicchioli ref opened new avenue astrobiology massively expanding number possible extraterrestrial habitats characterization organisms environments evolutionary pathways considered crucial component understanding life might evolve elsewhere


extremotolerant microorganisms contributed field astrobiology extreme radiation tolerance presence dna protection proteins may provide answers whether life survive away protection earth 's atmosphere jupiter 's moon europa ref name cavicchioli ref name galileo saturn 's moon enceladus ref name kazan considered likely locations extant extraterrestrial life solar system due subsurface water oceans radiogenic tidal heating enables liquid water exist ref name trixler origin life known abiogenesis distinct evolution life another ongoing field


research oparin haldane postulated conditions early earth conducive formation organic compounds inorganic elements thus formation many chemicals common forms life see today study process known prebiotic chemistry made progress still unclear whether life could formed manner earth alternative hypothesis panspermia first elements life may formed another planet even favorable conditions even interstellar


space asteroids etc carried earth cosmic dust permeating universe contains complex organic compounds amorphous organic solids mixed aromatic aliphatic structure could created naturally rapidly stars ref name space ref ref name sciencedaily ref ref name nature ref scientist suggested compounds may related development life earth said case life earth may easier time getting started organics serve basic ingredients life ref name space carbon universe may


associated polycyclic aromatic hydrocarbons pahs possible starting materials formation life pahs seem formed shortly big bang widespread throughout universe associated new stars exoplanets ref name nasa ref pahs subjected interstellar medium conditions transformed hydrogenation oxygenation hydroxylation complex organics step along path toward amino acids nucleotides raw materials proteins dna respectively ref name space ref ref name ajl ref october astronomers proposed idea detecting life distant planets studying shadows trees certain times


day find patterns could detected observation exoplanets ref name ut ref ref name ija ref astroecology astroecology concerns interactions life space environments resources planets asteroids comets larger scale astroecology concerns resources life stars galaxy cosmological future astroecology attempts quantify future life space addressing area astrobiology experimental astroecology investigates resources planetary soils using actual space materials meteorites ref name astroecologyicarus ref results suggest martian carbonaceous chondrite materials support bacteria algae plant asparagus potato cultures high soil


fertilities results support life could survived early aqueous asteroids similar materials imported earth dust comets meteorites asteroid materials used soil future space colonies ref name astroecologyicarus ref name astroecologyastrobiology ref largest scale cosmoecology concerns life universe cosmological times main sources energy may red giant stars white red dwarf stars sustaining life sup sup years ref name astroecologyicarus ref name astroecologyjbis ref astroecologists suggest mathematical models may quantify potential amounts


future life space allowing comparable expansion biodiversity potentially leading diverse intelligent life forms astrogeology astrogeology planetary science discipline concerned geology celestial bodies planets moons asteroids comets meteorites information gathered discipline allows measure planet 's natural satellite 's potential develop sustain life planetary habitability additional discipline astrogeology geochemistry involves study chemical composition earth planets chemical processes reactions govern composition rocks


soils cycles matter energy interaction hydrosphere atmosphere planet specializations include cosmochemistry biochemistry organic geochemistry fossil record provides oldest known evidence life earth examining fossil evidence paleontologists able better understand types organisms arose early earth regions earth pilbara western australia mcmurdo dry valleys antarctica also considered geological analogs regions mars might able provide clues


life life might arise independently earth expected use many similar identical building blocks also expected biochemical qualities unique life comparable impact elsewhere solar system relative abundances chemicals key survival whatever may could betray presence whatever extraterrestrial life may tendency chemically alter environment might give away life solar system europa due ocean exists icy surface might host form microbial life people


long speculated possibility life settings earth however speculation nature life elsewhere often paid little heed constraints imposed nature biochemistry ref name pace ref likelihood life throughout universe probably carbon based suggested fact carbon one abundant higher elements two natural atoms carbon silicon known serve backbones molecules sufficiently large carry biological information structural basis life one carbon 's important features unlike


silicon readily engage formation chemical bonds many atoms thereby allowing chemical versatility required conduct reactions biological metabolism propagation discussion solar system life might occur limited historically understanding life relies ultimately light warmth sun therefore restricted surfaces planets ref name pace four likely candidates life solar system planet mars jovian moon europa saturn 's moons titan ref name europa ref ref name euroupdate ref ref name titan ref enceladus ref name kazan ref ref name lovett ref mars enceladus


europa considered likely candidates search life primarily may underground liquid water molecule essential life know use solvent cells ref name autogenerated water mars found frozen polar ice caps newly carved gullies recently observed mars suggest liquid water may exist least transiently planet 's surface martian low temperatures low pressure liquid water likely highly saline europa enceladus large global oceans liquid water exist beneath moons'


icy outer crusts ref name galileo ref ref name europa ref name euroupdate water may warmed liquid state volcanic vents ocean floor primary source heat probably tidal heating december nasa reported detection clay like minerals specifically phyllosilicates often associated organic materials icy crust europa ref name nasa ref presence minerals may result collision asteroid comet according scientists ref name nasa additionally june astronomers reported detection complex macromolecular organics enceladus ref name nat ref


according nasa scientists may emerging habitable spot beyond earth solar system life know ref name kazan ref name lovett another planetary body could potentially sustain extraterrestrial life saturn 's largest moon titan ref name titan titan described conditions similar early earth surface scientists discovered first liquid lakes outside earth lakes seem composed ethane methane water scientists think possible liquid hydrocarbons might take place water living cells


mediocrity assumed famed astronomers frank drake carl sagan others principle mediocrity suggests life earth exceptional likely found innumerable worlds research systematic search possible life outside earth valid multidisciplinary scientific endeavor however hypotheses predictions existence origin vary widely present development hypotheses firmly grounded science may considered astrobiology 's concrete practical application proposed viruses likely encountered life bearing planets ref name astro ref


may present even biological cells research outcomes work nasa access date june ref ref name ea ref center evidence extraterrestrial life identified examination allan hills meteorite recovered antarctica originated mars thought david mckay well scientists contain microfossils extraterrestrial origin interpretation controversial ref name disbelief ref ref name life ref ref name mckay ref asteroid may transported life earth ref name yamato second largest meteorite mars found earth microscopic level spheres


found meteorite rich carbon compared surrounding areas lack spheres carbon rich spheres may formed biotic activity according nasa scientists ref name nasa ref ref name aj ref ref name sp ref march richard b hoover scientist marshall space flight center speculated finding alleged microfossils similar cyanobacteria ci carbonaceous meteorites fringe ''journal cosmology'' story widely reported mainstream media ref name tenney ref ref name hoover ref however nasa formally distanced hoover 's claim according american astrophysicist neil degrasse tyson moment life


earth known life universe compelling arguments suggest alone extreme environments earth march researchers reported microbial life forms thrive mariana trench deepest spot earth ref name ls ref ref name ng ref researchers reported microbes thrive inside rocks sea floor ocean coast northwestern united states ref name ls ref name ls ref according one researchers find microbes everywhere 're extremely adaptable conditions survive wherever ref name ls evidence


perchlorates found throughout solar system specifically mars dr kennda lynch discovered first known instance perchlorates perchlorates reducing microbes paleolake pilot valley utah finds expand potential habitability certain niches planets methane spectral signature methane detected martian atmosphere earth based telescopes well ''mars express'' orbiter solar radiation cosmic radiation methane predicted disappear martian atmosphere within several years gas must actively replenished order


maintain present concentration ref name results ref ref name fourier spec ref june nasa announced cyclical seasonal variation atmospheric methane may produced geological biological sources ref name nasa ref ref name nasa vid ref ref name spc ref european exomars trace gas orbiter currently measuring mapping atmospheric methane planetary systems possible exoplanets may moons solid surfaces liquid oceans hospitable planets far discovered outside solar system hot gas giants thought inhospitable life yet known whether solar system


warm rocky metal rich inner planet earth aberrant composition improved detection methods increased observation time undoubtedly discover planetary systems possibly like example nasa 's kepler mission seeks discover earth sized planets around stars measuring minute changes star 's light curve planet passes star spacecraft progress infrared astronomy submillimeter astronomy revealed constituents star systems planetary habitability efforts answer questions abundance potentially habitable planets habitable zones chemical precursors


much success numerous extrasolar planets detected using wobble method transit method showing planets around stars numerous previously postulated first earth sized extrasolar planet discovered within star 's habitable zone gliese c ref name gliese ref extremophiles studying extremophiles useful understanding possible origin life earth well finding likely candidates future colonization planets aim detect organisms able survive space travel conditions maintain proliferating capacity


environments still able restart cellular growth capable effectively protecting dna membrane proteins integrity different extreme conditions desiccation temperatures nbsp c uvc c ray radiation also able repair damage produced space environment locations earth particularly well suited astrobiological studies extremophiles example valeria souza colleagues proposed cuatro ci negas basin coahuila mexico could serve astrobiological precambrian park due similarity ecosystems earlier time earth 's history multicellular life began


dominate understanding extremophilic organisms survive earth 's extreme environments also understand microorganisms could survived space travel panspermia hypothesis could possible missions research environmental limits life workings extreme ecosystems ongoing enabling researchers better predict planetary environments might likely harbor life missions ''phoenix'' lander mars science laboratory exomars mars rover mars ''cassini'' probe saturn 's moons aim explore possibilities life planets


solar system ''viking'' program two viking landers carried four types biological experiments surface mars late mars landers carry experiments looking specifically metabolism current microbial life mars landers used robotic arm collect soil samples sealed test containers craft two landers identical tests carried two places mars' surface viking near equator viking north ref name chambers ref result inconclusive still disputed


scientists ref name bianciardi ref ref name discovery ref ref name navarro ref ref name paepe ref norman horowitz chief jet propulsion laboratory bioscience section mariner viking missions horowitz considered great versatility carbon atom makes element likely provide solutions even exotic solutions problems survival life planets ref name horowitz horowitz nh utopia back search life solar system new york wh freeman company ref however also considered conditions found mars incompatible carbon based


exposure organic chemicals biological samples outer space low earth orbit ref name home ref mars science laboratory mars science laboratory msl mission landed ''curiosity'' rover currently operation mars ref name mslnamewebsite ref launched november landed gale crater august ref name gale crater mission objectives help assess mars' habitability determine whether mars ever able support life ref name msl main page ref collect data future human mission study martian geology climate assess role water essential ingredient


rover perseverance jezero crater february investigate environments mars relevant astrobiology investigate surface geological processes history including assessment past habitability potential preservation biosignatures biomolecules within accessible geological materials ref name cowing ref science definition team proposing rover collect package least samples rock cores soil later mission bring back definitive analysis laboratories earth rover could make measurements technology demonstrations help designers human expedition understand hazards posed


martian dust demonstrate collect carbon dioxide co sub sub could resource making molecular oxygen sub sub rocket fuel ref name goals ref ref name faq ref ''europa clipper'' ''europa clipper'' mission planned nasa launch conduct detailed reconnaissance jupiter 's moon europa investigate whether internal ocean could harbor conditions suitable life ref name missions ref ref name fpe ref also aid selection future landing sites ref name europa lander ref proposed concepts ''icebreaker life'' ''icebreaker life'' lander mission proposed nasa 's discovery program launch opportunity ref


name 'icebreaker ' ref selected development would stationary lander would near copy successful ''phoenix'' would carried upgraded astrobiology scientific payload including meter long core drill sample ice cemented ground northern plains conduct search organic molecules evidence current past life mars ref name astrobiomag ref ref name lpi ref one key goals ''icebreaker life'' mission test hypothesis ice rich ground polar regions significant concentrations organics due protection


ice oxidants radiation ''journey enceladus titan'' ''journey enceladus titan'' ''jet'' astrobiology mission concept assess habitability potential saturn 's moons enceladus titan means orbiter ref name sotin ref ref name jet ref ref name lcpm ref ''enceladus life finder'' ''enceladus life finder'' ''elf'' proposed astrobiology mission concept space probe intended assess habitability internal aquatic ocean enceladus saturn 's sixth largest moon ref name lpsc ref ref name contestants ref ''life investigation enceladus'' ''life investigation enceladus'' ''life'' proposed astrobiology sample return mission concept spacecraft would enter saturn orbit


enable multiple flybys enceladus' icy plumes collect icy plume particles volatiles return earth capsule spacecraft may sample enceladus' plumes e ring saturn upper atmosphere titan ref name astro ref ref name porco ref ref name doc ref ''oceanus'' ''oceanus'' orbiter proposed new frontiers mission would travel moon saturn titan assess habitability ref name sotin ref ''oceanus'' objectives reveal titan 's organic chemistry geology gravity topography collect reconnaissance data catalog organics determine may interact liquid


water ''explorer enceladus titan'' ''explorer enceladus titan'' '''e sup sup t''' orbiter mission concept would investigate evolution habitability saturnian satellites enceladus titan mission concept proposed european space agency ref name 'e ' ref see also http wwwastrobiologycom astrobiologycom top ranked news source astrobiology '''' ''the living cosmos'' references bibliography http wwwjournalscambridgeorg jid ija ''international journal astrobiology'' published cambridge university press forum practitioners interdisciplinary field https webarchiveorg web http wwwliebertpubcom publicationaspxpub id ''astrobiology'' published mary ann liebert inc peer reviewed journal explores origins life evolution


beyond https webarchiveorg web http wwwastrobiologysurveyorg astrobiology survey introductory course astrobiology https wwwnasagov feature nasa search life astrobiology solar system beyond summary search life beyond earth nasa june extraterrestrial life origin life astronomical sub disciplines branches biology speculative evolution


nasa wake turbulence study wallops island vortex created passage aircraft wing revealed smoke vortices one many phenomena associated study aerodynamics '''aerodynamics''' greek ''aero'' air dynamics study motion air particularly affected solid object airplane wing sub field fluid dynamics gas dynamics many aspects aerodynamics theory common fields term ''aerodynamics'' often used synonymously gas dynamics difference


gas dynamics applies study motion gases limited air formal study aerodynamics began modern sense eighteenth century although observations fundamental concepts aerodynamic drag recorded much earlier early efforts aerodynamics directed toward achieving heavier air flight first demonstrated otto lilienthal since use aerodynamics mathematical analysis empirical approximations wind tunnel experimentation computer simulations formed rational basis development heavier air flight


number technologies recent work aerodynamics focused issues related compressible flow turbulence boundary layers become increasingly computational nature history modern aerodynamics dates back seventeenth century aerodynamic forces harnessed humans thousands years sailboats windmills images stories flight appear throughout recorded history ancient greek legend icarus daedalus fundamental concepts continuum drag pressure gradients appear work aristotle archimedes ref name andersonhist sir isaac newton


became first person develop theory air resistance making one first aerodynamicists dutch swiss mathematician daniel bernoulli followed ''hydrodynamica'' described fundamental relationship pressure density flow velocity incompressible flow known today bernoulli 's principle provides one method calculating aerodynamic lift leonhard euler published general euler equations could applied compressible incompressible flows euler equations extended incorporate effects viscosity first half resulting navier stokes equations


navier stokes equations general governing equations fluid flow difficult solve flow around simplest shapes replica wright brothers' wind tunnel display virginia air space center wind tunnels key development validation laws aerodynamics sir george cayley became first person identify four aerodynamic forces flight weight lift drag thrust well relationships ref name aernav ''cayley george'' aerial navigation http wwwaeronauticsnasagov fap onaerialnavigationpt pdf part http wwwaeronauticsnasagov fap onaerialnavigationpt pdf part


http wwwaeronauticsnasagov fap onaerialnavigationpt pdf part ''nicholson 's journal natural philosophy'' via nasa http inventionpsychologymsstateedu cayley cayleyhtml raw text retrieved may ref outlined path toward achieving heavier air flight next century francis herbert wenham constructed first wind tunnel allowing precise measurements aerodynamic forces drag theories developed jean le rond d'alembert gustav kirchhoff lord rayleigh charles renard french aeronautical engineer became first person reasonably predict power needed sustained flight otto lilienthal first person become highly successful glider flights


also first propose thin curved airfoils would produce high lift low drag building developments well research carried wind tunnel wright brothers flew first powered airplane december time first flights frederick w lanchester martin kutta nikolai zhukovsky independently created theories connected circulation fluid flow lift kutta zhukovsky went develop two dimensional wing theory expanding upon work lanchester ludwig prandtl credited developing mathematics behind thin airfoil


lifting line theories well work boundary layers aircraft speed increased designers began encounter challenges associated air compressibility speeds near speed sound differences airflow conditions lead problems aircraft control increased drag due shock waves threat structural failure due aeroelastic flutter ratio flow speed speed sound named mach number ernst mach one first investigate properties supersonic flow macquorn rankine pierre henri hugoniot independently developed


theory flow properties shock wave jakob ackeret led initial work calculating lift drag supersonic airfoils theodore von k rm n hugh latimer dryden introduced term transonic describe flow speeds critical mach number mach drag increases rapidly rapid increase drag led aerodynamicists aviators disagree whether supersonic flight achievable sound barrier broken using bell x aircraft time sound barrier broken aerodynamicists' understanding subsonic low supersonic flow