waashk/20ng huggingface dataset:
In article <1993Apr28.141606.17449@lambda.msfc.nasa.gov>, bday@lambda.msfc.nasa.gov (Brian Day) writes:  > rdouglas@stsci.edu (Rob Douglas) writes: >  >>[...]  But try to land a shuttle with that big huge telescope in the  >>back and you could have problems.  The shuttle just isn't designed to land  >>with that much weight in the payload. >  > Is HST really _that_ much heavier than a Spacelab ??? >   I hate to belabor the obvious once again, but if there had been an Orbiter emergency in the early stages of the original HST deployment mission, they would have HAD to land with HST in the bay.   Indeed they were worried about that.  One concern was the possibility that they would lose a motor or something on the way up, and make orbit but one that was too low to give HST a useful lifetime against atmospheric drag.   I believe the decision was to deploy HST even if the projected lifetime was as short as six months.  In fact we got an excellent orbit, on the upper envelope of what the Shuttle can do.  I have never heard of any serious consideration that HST might be brought  down for refurbishment.  You would have the horrendous cost of transporting, cleaning, re-testing, and re-certifying all the hardware on the ground, in addition to the lost observing time and the cost of a second deployment  mission with the risks that we might not get such a good orbit the second  time.  And, you would probably STILL need a (third) servicing mission in a  few years as gyros and other components wear out.  Better to have two  servicing missions in space (which could well happen) than to bring HST down  and take it up again.
In article <1993Apr5.160550.7592@mksol.dseg.ti.com> mccall@mksol.dseg.ti.com (fred j mccall 575-3539) writes:  >>Why can't the government just be a tennant?  >I think this would be a great way to build it, but unfortunately >current spending rules don't permit it to be workable.   Actually, that is no longer true. In the last few years Congress has ammended laws to provide whatever is needed. Note that both Spacehab and Comet are funded this way.  The problems aren't legal nor technical. The problem is NASA's culture.    Allen
[questions and issues WRT congress raised and discussed}  Dennis Replies; >Now black when it is white is just white. Except that when black is called >white money is put into the system in a study to find out just when it is >justified to call black, white.  It is also apparant that when white is called >black, just the opposite occurs. Now white is a color, but when white is >called black, it calls into question the validity of the color spectrum. ... >It is a given however that NASA nor the military, whose competence in >differentating black from white is well known (remember the black and >white paint on the Saturn V rocket?) That nothing will occur here either. >When black and white are used by congress, who cares nothing for results, >just more money for pork barrel jobs brought about by the black/white >controversy....  Dennis, why must you always see things in black and white terms? :-)  -Tommy Mac ------------------------------------------------------------------------- Tom McWilliams 517-355-2178 wk   \\ As the radius of vision increases, 18084tm@ibm.cl.msu.edu 336-9591 hm \\ the circumference of mystery grows.
In article <1993Apr18.014305.28536@sfu.ca>, Leigh Palmer <palmer@sfu.ca> writes: > In article <C5nGxq.663@zoo.toronto.edu> Henry Spencer, > henry@zoo.toronto.edu writes: > >The National Air & Space Museum has both the prototype and the film. > >When I was there, some years ago, they had the prototype on display and > >the film continuously repeating. >  > Great! I'll visit the National Air and Space Museum at the end of the > month with my wife, who was also working at General Atomic at the time. > Once again netnews has enriched my life.  Sorry to put a damper on your plans, but I was there three weeks ago and it wasn't there.  Not that I would have known to look for it, of course, but I combed the space exhibits pretty thoroughly and something like that would have caught my attention instantly.
Background: The Orion spacedrive was a theoretical concept.  It would be a drive using thermonuclear explosions to drive a spacecraft. The idea was that you'd detonate devices with somewhere from one to ten megatons yield behind a "pusher plate" attached to the main spacecraft.  The shock wave from the explosions would transfer momentum to the ship.    Now, in an atmosphere I can see this.  The energy of the explosion heats the atmosphere, which expands explosively and slams a shock wave into the pusher plate.  But in a vacuum, only two things I can see are going to hit the plate: fission/fusion products (barium, krypton, helium, neutrons, evaporated bomb casing) and electromagnetic radiation (gammas mostly, some light/heat from irradiated fission products).    Would this work?  I can't see the EM radiation impelling very much momentum (especially given the mass of the pusher plate), and it seems to me you're going to get more momentum transfer throwing the bombs out the back of the ship than you get from detonating them once they're there.    I must be missing something.  Would someone enlighten me via email?    Thanks.  --  	--Jim
In article <1993May1.044441.1@aurora.alaska.edu> nsmca@aurora.alaska.edu writes: >Okay, the earth has a magnetic field (unless someone missed something?) > >Okay if you put a object in the earth magnetic field, it produces electricty..  No, if you put a conductor in a changing magnetic field, it produces a voltage. The two ways you can do that with a permanent magnet is to move the magnet or move the conductor.  The slow shifting of the Earth's magnetic field isn't really significant, especially when you consider how weak the Earth's magnetic field is to begin with.  >Now the question. Can you use electricity to power a space/low earth orbit >vehicle? and i fyou can, can you use the magnetic field of the earth to power >it??  Well, it would require generating an incredibly large magnetic field to repel the Earth's magnetic field (as a magnet can repel another magnet).  Of course, this force only works in one direction, and the magnetic field generated has to be unimaginably powerful.  Magnetic repulsion drops off as 1/r^3, and the earth's magnetic field on the surface is already very weak.  It would require some sort of unknown superconductor, and special nonmagnetic construction. And seriously hardenned electronics (optical computers, perhaps).  And the physiological danger would be significant (due to the iron content in our blood, among other things).  In other words, forget it.  >Can the idea of a "dragless" satellite be used in part to create the electrical >field? > >After all the dragless satellite is (I might be wrong), a suspended between to >pilons, the the pilons compensate for drag.. I think I know what I want to say, >just not sure how to say it.. > >A dragless satellite sounds interestingly enough liek a generator.  I missed out on the "dragless satellite" thread, but it sounds totally bogus, from this little bit.
Teflon? A contribution from the space program? Since the French were using Teflon on household items in the early 1950's, it is unlikely that it was invented by NASA. As for pacemakers and calculators, again those are anecdotally connected with NASA.
==========================                                OZONE GIF IMAGES                                 April 15, 1993                          ==========================       Two GIF images of the ozone maps over the northern and southern hemispheres are now available at the JPL Info public access site.  These maps were produced by the Microwave Limb Sounder aboard the Upper Atmosphere Research Satellite (UARS), and are courtesy of the Public Information Office at JPL.  Note that the images are in GIF89a format, so make sure your display software supports this format (as opposed to the older GIF87a format).  The caption files accompanying the images are appended at the end of this message, as well as being embedded in the images.  The images are available by dialup modem at +1 (818) 354-1333, up to 9600 bps, parameters N-8-1, or by using anonymous ftp to:          ftp:      pubinfo.jpl.nasa.gov (128.149.6.2)         user:     anonymous         cd:       news (will be moved to the images directory in 30 days)         files:    ozone93a.gif - Northern hemisphere                   ozone93b.gif - Southern hemisphere       Also, photographic prints of these images can be ordered from Newell Color Lab listed below.  Refer to the P number associated with the images when ordering.       Newell Color Lab      221 N. Westmoreland Avenue      Los Angeles CA 90064      Telephone: (213) 380-2980      FAX: (213) 739-6984  -------------------------------------------------------------------------- ozone93a.gif  PUBLIC INFORMATION OFFICE JET PROPULSION LABORATORY CALIFORNIA INSTITUTE OF TECHNOLOGY NATIONAL AERONAUTICS AND SPACE ADMINISTRATION PASADENA, CALIF. 91109.  TELEPHONE (818) 354-5011  PHOTO                                                     P-42210                                                    April 14, 1993  This graphic depicts chlorine monoxide and ozone over Earth's northern hemisphere in February 1992 and 1993.  These maps were produced by the Microwave Limb Sounder aboard the Upper Atmosphere Research Satellite.  The chlorine monoxide (ClO) maps (left) are for a layer about 20 kilometers (66,000 feet) above the Earth's surface on February 17, 1992 (above) and 1993 (below).  The ozone maps show the total amount above an altitude of about 12 kilometers (41,000 feet) averaged over the period from February 15 to March 6 for the two years.  The Microwave Limb Sounder, developed and operated by a team at NASA's Jet Propulsion Laboratory, is one of several instruments on the Goddard Space Flight Center's Upper Atmosphere Research Satellite, launched in September 1991.  -------------------------------------------------------------------------- ozone93b.gif  PUBLIC INFORMATION OFFICE JET PROPULSION LABORATORY CALIFORNIA INSTITUTE OF TECHNOLOGY NATIONAL AERONAUTICS AND SPACE ADMINISTRATION PASADENA, CALIF. 91109.  TELEPHONE (818) 354-5011  PHOTO CAPTION                                             P-42211                                                    April 14, 1993
Press Release No.19-93 Paris, 22 April 1993  Users of ESA's Olympus satellite report on the outcome of their experiments  "Today Europe's space telecommunications sector would not be blossoming as it now does, had OLYMPUS not provided a testbed for the technologies and services of the 1990s". This summarises the general conclusions of 135 speakers and 300 participants at the Conference on Olympus Utilisation held in Seville on 20-22-April 1993. The conference was organised by the European Space Agency (ESA) and the Spanish Centre for the Development of Industrial Technology (CDTI).  OLYMPUS has been particularly useful : -      in bringing satellite telecommunications to thousands of        new users, thanks to satellite terminals with very small        antennas (VSATs). OLYMPUS experiments have tested        data transmission, videoconferencing, business television,        distance teaching and rural telephony, to give but a few        examples.  -      in opening the door to new telecommunications services        which could not be accommodated on the crowded lower-        frequency bands; OLYMPUS was the first satellite over        Europe to offer capacity in the 20/30 GHz band.  -      in establishing two-way data relay links  OLYMPUS        received for the first time in Europe, over several months,        high-volume data from a low-Earth orbiting spacecraft and        then distributed it to various centres in Europe.  When OLYMPUS was launched on 12 July 1989 it was the world's largest telecommunications satellite; and no other satellite has yet equalled its versatility in combining four different payloads in a wide variety of frequency bands.  OLYMPUS users range from individual experimenters to some of the world's largest businesses. Access to the satellite is given in order to test new telecommunications techniques or services; over the past four years some 200 companies and organisations made use of this opportunity, as well as over 100 members of the EUROSTEP distance-learning organisation.    As the new technologies and services tested by these OLYMPUS users enter the commercial market, they then make use of operational satellites such as those of EUTELSAT.
>There is a guy in NASA Johnson Space Center  that might answer  >your question. I do not have his name right now but if you follow  >up I can dig that out for you.
Others said: # >Coca Cola company will want to paint the moon red and white.  (Well, # >if not this moon, then a moon of Jupiter)...  This reminds me of the old Arthur C. Clarke story about the Coca Cola ad stashed inside an experiment.
In article <1993Apr20.120311.1@pa881a.inland.com> Don Schiewer, schiewer@pa881a.inland.com writes: >What is the deal with life on Mars?  I save the "face" and heard  >associated theories. (which sound thin to me) > >Are we going back to Mars to look at this face agian? >Does anyone buy all the life theories?
SOmebody mentioned  a re-boost of HST during this mission,  meaning that Weight is a very tight  margin on this  mission.  How will said re-boost be done?  Grapple, HST,  stow it in Cargo bay,  do OMS burn to high altitude,    unstow  HST,   repair  gyros,  costar install,  fix solar arrays,  then return to earth?  My guess is  why  bother with  usingthe shuttle to reboost?  why not  grapple,  do all said fixes,   bolt a small  liquid  fueled thruster module  to  HST,   then let it make the re-boost.  it has to be cheaper on mass then usingthe shuttle as a tug.   that way, now that they are going to need at least 5  spacewalks,  then they can carry an EDO pallet,  and  sit on station and even  maybe do the  solar array tilt  motor  fix.
In article <1993Apr21.134436.26140@mksol.dseg.ti.com> mccall@mksol.dseg.ti.com (fred j mccall 575-3539) writes: >>>(given that I've heard the Shuttle software rated as Level 5 ... >>Level 5?  Out of how many? ... > >... Also keep in mind that it was >*not* achieved through the use of sophisticated tools, but rather >through a 'brute force and ignorance' attack on the problem during the >Challenger standdown - they simply threw hundreds of people at it and >did the whole process by hand...  I think this is a little inaccurate, based on Feynman's account of the software-development process *before* the standdown.  Fred is basically correct:  no sophisticated tools, just a lot of effort and painstaking care.  But they got this one right *before* Challenger; Feynman cited the software people as exemplary compared to the engine people.  (He also noted that the software people were starting to feel management pressure to cut corners, but hadn't had to give in to it much yet.)  Among other things, the software people worked very hard to get things right for the major pre-flight simulations, and considered a failure during those simulations to be nearly as bad as an in-flight failure. As a result, the number of major-simulation failures could be counted on one hand, and the number of in-flight failures was zero.  As Fred mentioned elsewhere, this applies only to the flight software. Software that runs experiments is typically mostly put together by the experimenters, and gets nowhere near the same level of Tender Loving Care. (None of the experimenters could afford it.)
yamauchi@ces.cwru.edu (Brian Yamauchi) writes:  >Any comments on the absorbtion of the Office of Exploration into the >Office of Space Sciences and the reassignment of Griffin to the "Chief >Engineer" position?  Is this just a meaningless administrative >shuffle, or does this bode ill for SEI?  Unfortunately, things have been boding ill (is that a legitimate conjugation?) for a while.  While the Office of Exploration had some great ideas, they never got much money.  I've heard good things about Griffin, but it's hard to want him back in a job where he couldn't do anything.  >Does anyone know what his new duties will be?  The group examining the Freedom-based space station redesign proposals is  headed by Michael Griffin, "NASA's cheif engineer" in the words of Space News. I believe this is him.
nsmca@aurora.alaska.edu, University of Alaska Fairbanks writes:  [A GOOD DEAL OF HEALTHY IF NOT DEEPLY THOUGHT OUT IDEALISM DELETED BELOW.]  >Major question is if you decide to mine the moon or Mars, who will stop you? >[...] Can the truly inforce it? [...]   If their parent company does business (and they will) on the face of the Earth then they are vulnerable to govt. sanctions.  Yes they can be stopped.  >If you go to the moon as declare that you are now a soverign nation, who will >stop you from doing it. [...]     For the first 100 - 500 (IMHO) years nobody will have to.  The colonists will be too dependent on Earth too pull it off.  Eventually they will, history shows us that.  >Also once you have the means to mine the moon (or whatever) then just do it.  >The UN if done right can be made to be so busy with something else, they will >not care [...]  What exactly do you mean here?  Terrorism?  Start an international incident so your dream can come true?  Crack a few eggs to make the omelet?  This sounds fairly irresponsible.   >Basically what I am saying is where is that drive of yeasteryears to go a >little bit farther out, to do jus ta  little bit more, and to tell the crown to >piss off.. If my ancestors thought the way many today think, Id have been born >in Central Europe just north of the Black Sea..          Again, the tie that binds will be much stronger for space colonists than any immigrants that have gone before.  Even those intrepid Asian explorers that crossed the Bering land bridge did not have to carry their air on their backs.  ==     >Michael Adams, nsmca@acad3.alaska.edu -- I'm not high, just jacked    Keep the dream alive, maybe dream it a little more cogently.
> > > Also, peri[jove]s of Gehrels3 were: > > >  > > > April  1973     83 jupiter radii > > > August 1970     ~3 jupiter radii  > > Where 1 Jupiter radius = 71,000 km = 44,000 mi = 0.0005 AU. ...  > Sorry, _perijoves_...I'm not used to talking this language.  Thanks again.  One final question.  The name Gehrels wasn't known to me before this thread came up, but the May issue of Scientific American has an article about the "Inconstant Cosmos", with a photo of Neil Gehrels, project scientist for NASA's Compton Gamma Ray Observatory. Same person? --  Mark Brader, SoftQuad Inc., Toronto	"Information! ... We want information!" utzoo!sq!msb, msb@sq.com				-- The Prisoner
In article <1r6aqr$dnv@access.digex.net>, prb@access (Pat) writes: >Voyager  has the unusual  luck to be on a stable trajectory out of the >solar system.   All it's doing is collecting  fields  data,  and routinely >squirting it down.  One of the mariners is also in stable >solar orbit,  and still providing similiar  solar data.    There are no Mariner craft from which we are still receiving data.  I believe you are referring to one or more of Pioneers 6 through 9 (launched from December 1965 through November 1968), which were put into solar orbits to study interplanetary space.  I recall reading that at least one of them was still functioning 25 years after launch.
Forwarded from the Mars Observer Project                       MARS OBSERVER STATUS REPORT                            April 28, 1993                             12:40 PM PDT  Flight Sequence C9 is active as of 00:11 AM, Tuesday, April 27.  With activities beginning at shortly before 5:00 AM yesterday, C9 commanded the spacecraft to execute a series of slews and rolls to provide the MAG (Magnetometer) Team data points in varying spacecraft attitudes and orientations for the purpose of better characterizing the spacecraft-generated magnetic field and its effect on their instrument.  The spacecraft was commanded back to Sun Star Init state at 9:07 AM to re-establish Inertial Reference.  Transition back to Array Normal Spin began at 11:17 AM, after which the sequence powered on the on-board transmitter at 11:18 AM.  Telemetry reacquisition occurred at approximately 11:30 AM at the 4 KBS Science and Engineering downlink data rate on the High Gain Antenna.  Subsystem engineers report that all systems appear to be nominal.  The command to terminate using the Low Gain Antenna for uplink was sent at 12:31 PM.  Uplink and Downlink are currently via the HGA.  MAG Calibration data has been recorded on Digital Tape Recorders 2 and 3. Playback of DTR 2 is scheduled to take place tomorrow morning between 8:11 AM and 12:42 PM.  Playback of DTR 3 is scheduled to take place tomorrow evening beginning at 11:57 PM and ending at 4:28 AM on Friday. DTR playback will be performed via the High Gain Antenna at 42,667 bits per second.  Upon verification of successful DTR playbacks, downlink will be maintained at the 4K S & E rate.
In article <C4zHKw.3Dn@zoo.toronto.edu>, henry@zoo.toronto.edu (Henry Spencer) writes: > In article <2736@snap> paj@uk.co.gec-mrc (Paul Johnson) writes: >>This bit interests me.  How much automatic control is there?  Is it >>purely autonomous or is there some degree of ground control? >  > The "stick-and-rudder man" is always the onboard computer.  The computer > normally gets its orders from a stored program, but they can be overridden > from the ground. >  >>How is >>the transition from aerodynamic flight (if thats what it is) to hover >>accomplished?  This is the really new part... >  > It's also one of the tricky parts.  There are four different ideas, and > DC-X will probably end up trying all of them.  (This is from talking to > Mitch Burnside Clapp, who's one of the DC-X test pilots, at Making Orbit.) >  > (1) Pop a drogue chute from the nose, light the engines once the thing > 	stabilizes base-first.  Simple and reliable.  Heavy shock loads > 	on an area of structure that doesn't otherwise carry major loads. > 	Needs a door in the "hot" part of the structure, a door whose > 	operation is mission-critical. >  > (2) Switch off pitch stability -- the DC is aerodynamically unstable at > 	subsonic speeds -- wait for it to flip, and catch it at 180 > 	degrees, then light engines.  A bit scary. >  > (3) Light the engines and use thrust vectoring to push the tail around. > 	Probably the preferred method in the long run.  Tricky because > 	of the fuel-feed plumbing:  the fuel will start off in the tops > 	of the tanks, then slop down to the bottoms during the flip. > 	Keeping the engines properly fed will be complicated. >  > (4) Build up speed in a dive, then pull up hard (losing a lot of speed, > 	this thing's L/D is not that great) until it's headed up and > 	the vertical velocity drops to zero, at which point it starts > 	to fall tail-first.  Light engines.  Also a bit scary, and you > 	probably don't have enough altitude left to try again. > --  > All work is one man's work.             | Henry Spencer @ U of Toronto Zoology >                     - Kipling           |  henry@zoo.toronto.edu  utzoo!henry  Since the DC-X is to take off horizontal, why not land that way?? Why do the Martian Landing thing..  Or am I missing something.. Don't know to much about DC-X and such.. (overly obvious?).  Why not just fall to earth like the russian crafts?? Parachute in then...  == Michael Adams, nsmca@acad3.alaska.edu -- I'm not high, just jacked