# Observatories/Astronomy

Historically, observatories [are] as simple as using or placing stably an astronomical sextant (for measuring the distance between stars) or Stonehenge (which has some alignments on astronomical phenomena). Most optical telescopes are housed within a dome or similar structure, to protect the delicate instruments from the elements. Telescope domes have a slit or other opening in the roof that can be opened during observing, and closed when the telescope is not in use. In most cases, the entire upper portion of the telescope dome can be rotated to allow the instrument to observe different sections of the night sky. Radio telescopes usually do not have domes.
There are "a plethora of observations from heavenly bodies which did not agree with each other despite being from the same astronomical entities."

## Astronomy

"The radio quasar 3C 454.3 underwent an exceptional optical outburst lasting more than 1 year and culminating in spring 2005. The maximum brightness detected was R = 12.0, which represents the most luminous quasar state thus far observed (MB ~ −31.4). In order to follow the emission behaviour of the source in detail, a large multiwavelength campaign was organized by the Whole Earth Blazar Telescope (WEBT). Continuous optical, near-IR and radio monitoring was performed in several bands. Two pointings by the Chandra and INTEGRAL satellites provided additional information at high energies in May 2005."
"The historical radio data are from the University of Michigan Radio Astronomy Observatory (UMRAO) and the Metsähovi Radio Observatory (Teräsranta et al. 2005, references therein, and unpublished data), while data from the Crimean (RT-22), MDSCC (PARTNeR), Medicina, Noto, and SAO RAS (RATAN-600) Observatories as well as data from the VLA/VLBA Polarization Calibration Database$^1$ contribute to the most recent part of the light curves."
"In order to have information on both the rising and decreasing phases of the outburst, data were collected from June 2004 to the end of September 2005. In total, 5584 UBV RI observations from 18 telescopes$^4$ were performed in this period; moreover, JHK data were taken at Campo Imperatore, Calar Alto, and Roque de los Muchachos (NOT). Radio data from 1 to 43 GHz were acquired at several telescopes, mentioned above."

## Observatories

Def. a place where stars, planets and other celestial bodies are observed is called an observatory.
The "Faulkes Telescope Project, sponsored by the Las Cumbres Observatory Global Telescope Network, provides students in the United Kingdom with free access to two high-powered robotic telescopes, one in Hawaii and the other in Australia, which the students are able to use remotely to carry out their own scientific investigations (http://faulkes-telescope.com/)."

## Planetary observatories

"The 0.6m Tortugas Mountain Observatory is used to monitor the temporal changes in the Jovian cloud deck and equatorial activity on Saturn. The data are collected with a CCD camera, archived at the NMSU astronomy department and made available to the Astronomical community through the NASA Planetary Data System Subnode. Images collected over the last 27 years are being used as a climatic data base to interpret the Hubble Space Telescope ~HST!, Galileo and Cassini data. Although funding has been reduced, simultaneous observations are scheduled when the 3.5 meter telescope is used for infrared imaging of Jupiter."

## Radiation observatory

Def. a device used to measure the heating power of electromagnetic radiation, especially that of solar radiation is called an actinometer.
Def. an actinometer used to measure solar radiation incident on a surface is called a pyranometer.
At right is an SR20 solar radiation sensor. It complies with the "secondary standard" specifications within the latest ISO and WMO standards.
Def. the "total solar radiation from sun and sky on a horizontal surface" is called the global radiation.
The Radiation Observatory, University of Bergen, Bergen, Norway, latitude 60° 24' N and longitude 5° 19' E, at 45 m elevation above sea level, uses one or more pyranometers to measure the Global Radiation.
A sensitivity check is made of each pyranometer against a standard using the sun/shade method on a cloudless day.
A sensitivity may be similar to 4.818 V/Wm$^{-2}$, which should be a small factor such as 1.0165 times the original sensitivity when first manufactured.
The diffuse (sky) radiation is measured by a pyranometer. "When measuring the sky radiation, the direct solar radiation is constantly shadowed off by means of a 6 cm diameter circular disc mounted on a 30 cm long rotating arm."
Def. a device that measures the intensity of solar radiation received on the surface of the earth is called a pyrheliometer.
The normal incidence beam radiation is measured by a normal incidence pyrheliometer with a known and calibrated sensitivity, e.g. 8.15 V/Wm$^{-2}$.
The pyrheliometer is mounted on an automatic solar tracker.
Def. a device that measures radiant energy is called a radiometer.
Ultraviolet radiation is measured by means of a total ultraviolet radiometer with a specific wavelength response such as 290 - 385 nm.
"For the measurement of long-wave radiation, a ventilated [...] pyrgeometer [...] with coated silicon hemisphere [is] used. This makes it possible to compute the [Downward Atmospheric Radiation], since the temperature of the instrument is also recorded."
"The [Duration of Sunshine] is measured by a Campbell-Stoke sunshine recorder with blue paper strips. The strips are read according to the rules of [the World Meteorological Organization] WMO [3]. Maximum possible duration gives the number of hours the sun is above the natural horizon, as found from the records on days with clear skies at sunrise or sunset. The [Duration of Sunshine] is also given as the number of minutes during which the [NIP records] irradiance above 120 Wm$^{-2}$ (with one instantaneous recording counted as 20 seconds)."
"The necessary routine calibrations of the pyranometers and the NIP pyrheliometer are carried out by means of the absolute self-calibrating cavity pyrheliometer [which in turn is] compared to the World Radiation Reference Scale (WRR)".

## Observatory geology

Observatory geology has two forms: the geological study necessary to put an observatory on a solid foundation to maximize telescope function through minimizing ground-based vibration and imaging terrain so that geological study may be performed.
"Images of Europa from the Galileo spacecraft [launch release at right from the shuttle Atlantis] show a surface with a complex history involving tectonic deformation, impact cratering, and possible emplacement of ice-rich materials and perhaps liquids on the surface. Differences in impact crater distributions suggest that some areas have been resurfaced more recently than others; Europa could experience current cryovolcanic and tectonic activity. Global-scale patterns of tectonic features suggest deformation resulting from non-synchronous rotation of Europa around Jupiter. Some regions of the lithosphere have been fractured, with icy plates separated and rotated into new positions. The dimensions of these plates suggest that the depth to liquid or mobile ice was only a few kilometers at the time of disruption. Some surfaces have also been upwarped, possibly by diapirs, cryomagmatic intrusions, or convective upwelling. In some places, this deformation has led to the development of chaotic terrain in which surface material has collapsed and/or been eroded"

## Theoretical observatory astronomy

A "'Theoretical Observatory' [...] decides which systems, sub-systems and sub-sub-systems should be recognizable, and which not. The result of this process [is] a Theoretically Observed Bright Multiple Star Catalogue or TOBMSC."
A computer code "decides which components would actually be identifiable, either as visual systems, as spectroscopic systems or as eclipsing systems."

## Entities

"In order that the [Virtual Astronomical Observatory] VAO would be seen as an entity that is of and for the research community, a dedicated not-for-profit company was established to manage the governance and business functions."
"The U.S. Virtual Astronomical Observatory (VAO; http://www.us-vao.org/) [...] goal is to enable new science through efficient integration of distributed multi-wavelength data."

## Sources

The "Great Observatories Origins Deep Survey (GOODS) [...] are primarily, but not exclusively, based on multi–band imaging data obtained with the Hubble Space Telescope (HST) and the Advanced Camera for Surveys (ACS). [...] Existing deep observations from the Chandra X-ray Observatory (CXO) and groundbased facilities are supplemented with new, deep imaging in the optical and near-infrared from the European Southern Observatory (ESO) and from the Kitt Peak National Observatory (KPNO) [includes deep] observations with the Space Infrared Telescope Facility (SIRTF) [and] at the Kitt Peak National Observatory, National Optical Astronomical Observatories".
"The astrometric solution for the z-band mosaics has been derived by a least-squares optimization of the position, orientation, x and y pixel scales, and axis skew of each tile and epoch, minimizing the inter-epoch variations of the estimated position for ~ 2000 sources."

## Objects

The top image at right shows the cupola or dome open with the automated telescopes visible of one of the Okno towers.
The Russian Okno system, four towers are at left, is an optoelectronic system for monitoring and surveillance of space objects integrated to the KRONA system of space recognition.
The installation, at lower right, is located in the mountains near Dushanbe, Tajikistan and Nurek Dam at an altitude of 2,200 meters, approximately latitude 38.280833 ° N longitude 69.224722 ° E.
It is a unique facility equipped with telescopes and radar control capable of tracking space objects orbiting the Earth at an altitude of 2,000 to 40,000 km.
The Okno system is fully automated, performs autonomous control sessions in real time and can only work at night, the role of the center is particularly important in emergency situations, such as a loss of communications with an artificial satellite.
At lower left is an image of the US counterpart, the Ground-based Electro-Optical Deep Space Surveillance (GEODSS) base at Diego Garcia, British Indian Ocean Territory latitude 7.41173°S and longitude 72.45222°E.

## Continua

"The CCD spectroscopic observations were performed with the 91-cm telescope at Okayama Astrophysical Observatory (OAO) and the 101-cm telescope at Bisei Astronomical Observatory (BAO) between July 23 and 27."
"The averaged signal to noise ratios (S/N) at the continuum level were 60-100 for OAO data using exposure times of 180-300 s, and 25-40 for BAO data using exposure times of 120 s respectively, which depend on the brightness of the object and the sky condition."

## Emissions

"For events observed at Beijing Astronomical Observatory and Ondrejov Observatory, we found that emissions took place at the cyclotron harmonics beginning from the third harmonic."

## Absorptions

"The first observational evidence of an absorption feature in the C$^+$ spectrum has been carried out by the Kuiper Astronomical Observatory toward the W51 H II region (Zmuidzinas 1987)."

## Bands

"The data on AG Peg were obtained with the ultraviolet broad-band photometers on the Orbiting Astronomical Observatory 2; a large ultraviolet flux was found and easily measured."

## Backgrounds

"The sky background depends strongly on the color filters used. For a dark night, it is smallest, around 20 electrons/pixel/140 seconds with the U filter, and largest, around 600 electrons/pixel/140 seconds with the R filter."
The "1 meter Schmidt telescope at the Venezuelan National Astronomical Observatory [is] located at Llano del Hato".

## Strong forces

"The molecular cloud Cepheus B is subject to strong forces both trying to compress and to disrupt it simultaneously."
The above is based "on observations collected at the Centro Astronómico Hispano Alemán, Calar Alto (Spain), operated by the Max Planck Institut für Astronomie, Heidelberg (FRG), and at the Observatorio Astronómico Nacional in Sierra San Pedro Mártir, Baja California (México)".

## Electromagnetics

"Electromagnetic radiation from galaxies gives information about the status of baryonic matter, ie, stars, gas, and dust."
The "data [was] collected at the Subaru Telescope, which is operated by the National Astronomical Observatory of Japan."
At right is a photograph of the Bernard-Lyot telescope at the Pic du Midi Observatory, Bigorre, France, at dusk with the dome moved to begin opening for observation. The high-sensitivity NARVAL spectropolarimeter installed on the Bernard-Lyot telescope was used to detect the Zeeman effect and thereby a magnetic field in the light emitted by the A0V star Vega.

## Meteors

"Reduced trajectory data and orbital elements are reported for 20 double-station meteors photographed at the NASA-NMSU meteor observatory during the winter of 1974/75."
The "meteor radar established at the Ondfejov Observatory of the Astronomical Institute of the Czechoslovak Academy of Sciences [...] measures meteor hourly rates, distances as well as velocities."
The "photographic apparatus at the Yale Observatory, designed mainly for the purpose of attempting to secure records of meteor trails, was put up in 1894 with the aid of a grant from the J. Lawrence Smith fund of the National Academy of Sciences."

## Cosmic rays

The Fred Lawrence Whipple Observatory is an astronomical observatory owned and operated by the Smithsonian Astrophysical Observatory (SAO) [with r]esearch activities [that] include imaging and spectroscopy of extragalactic, stellar, and planetary bodies, as well as gamma-ray and cosmic-ray astronomy.
The Pierre Auger Observatory is an international cosmic ray observatory designed to detect ultra-high-energy cosmic rays: single sub-atomic particles (protons or atomic nuclei) with energies beyond 10$^{20}$ [electronvolt] eV (about the energy of a tennis ball traveling at 80 km/h). These high energy particles have an estimated arrival rate of just 1 per km$^2$ per century, therefore the Auger Observatory has created a detection area the size of Rhode Island — over 3,000 km$^2$ (1,200 sq mi) — in order to record a large number of these events. It is located in western Argentina's Mendoza Province, in one of the South American Pampas.
The basic set-up consists of 1600 water tanks (water Cherenkov Detectors, similar to the Haverah Park experiment) distributed over 3,000 square kilometres (1,200 sq mi), along with four atmospheric fluorescence detectors (similar to the High Resolution Fly's Eye) overseeing the surface array.

## Neutrons

A "new detector to observe solar neutrons [has been in operation] since 1990 October 17 [...] at the Mount Norikura Cosmic Ray Laboratory (CRL) of [the] Institute for cosmic Ray Research, the University of Tokyo."
"On 1991 June 1, an active sunspot appeared at N25 E90 on the Sun (NOAA region 6659). The commencement of an enormous bright flare was observed at 03:37 UT on 1991 June 4 [...] The flare was classified as 3 B and the location was at N31 E70 of the solar surface."
"The solar neutron telescope [image at right] consists of 10 blocks of scintillator [...] and several lead plates which are used to place kinetic energies T$_n$ of incoming particles into three bands (50-360 MeV, 280-500 MeV, and ≥ 390 MeV)." The telescope is inclined to the direction of the Sun by 15°. The plane area of the detector is 1.0 m$^2$ and protected by lead plates (Pb) to eliminate gamma-ray and muon background from the side of the detector. The anti-coincident counter (A) is used to reject the muons and gamma rays, coming from the side of the detector and the top scintillators. (P) and (G) are used to identify the proton events and gamma rays. The central scintillator blocks are optically separated into 10 units.
"The horizontal scintillator just above the 10 vertical scintillators distinguishes neutral particles (neutrons) from the charged particles (mainly muons, protons and electrons)."
"Mount Norikura Cosmic-Ray Laboratory has an elevation of 2770 m above sea level. The geographical latitude is 36.10° N and the longitude is 137.55° E. The zenith angle of the Sun at 03:37 UT on June 4 is 18.9° and the solar neutron telescope was set at a zenith angle of 15° on this day."

## Protons

A "Proton Observatory [specifically, the] proton vector magnetometer, with a coil theodolite as its main part, permits measurements of the declination of the Earth's magnetic field in accordance with the method of addition."

## Electrons

"The ELectron Observatory (ELO) is a calorimeter designed to extend current data on the energy spectrum of cosmic-ray electrons to over 10 TeV, with the potential of detecting predicted structures imprinted on the electron flux by the acceleration process."

## Positrons

"The GAMMA-400 space observatory will provide precise measurements of gamma rays, electrons, and positrons in the energy range 0.1–3000 GeV."

## Neutrinos

The Baksan Neutrino Observatory (BNO) consists of the Baksan Underground Scintillation Telescope, located 300m below the surface, a gallium–germanium neutrino telescope (the [Soviet–American Gallium Experiment] SAGE experiment) located 3,500m deep, as well as a number of ground facilities.
The Extreme Universe Space Observatory (EUSO) is the first Space mission concept devoted to the investigation of cosmic rays and neutrinos of extreme energy (E > 5×10$^{19}$ eV). Using the Earth's atmosphere as a giant detector, the detection is performed by looking at the streak of fluorescence produced when such a particle interacts with the Earth's atmosphere.
The IceCube Neutrino Observatory (or simply IceCube) is a neutrino telescope constructed at the Amundsen-Scott South Pole Station in Antarctica.[1] Similar to its predecessor, the Antarctic Muon And Neutrino Detector Array (AMANDA), IceCube contains thousands of spherical optical sensors called Digital Optical Modules (DOMs), each with a photomultiplier tube (PMT) and a single board data acquisition computer which sends digital data to the counting house on the surface above the array.
IceCube was completed on 18 December, 2010, New Zealand time.
The Sudbury Neutrino Observatory detector at right was designed to detect solar neutrinos through their interactions with a large tank of heavy water. The detector turned on in May 1999, and was turned off on 28 November 2006.
The experiment observed the light produced by relativistic electrons in the water created by neutrino interactions. As relativistic electrons travel through a medium, they lose energy producing a cone of blue light through the Cerenkov effect, and it is this light that is directly detected.

## Gamma rays

Launched in 1991, The Compton Gamma Ray Observatory [carried aboard the] Burst and Transient Source Explorer (BATSE) instrument, an extremely sensitive gamma-ray detector. The BATSE searched the sky for gamma ray bursts (20 to >600 keV) and conducted full sky surveys for long-lived sources. It consisted of eight identical detector modules, one at each of the satellite's corners (left, right; front and back; top and bottom). Each module consisted of both a NaI(Tl) Large Area Detector (LAD) covering the 20 keV to ~2 MeV range, 50.48 cm in dia by 1.27 cm thick, and a 12.7 cm dia by 7.62 cm thick NaI Spectroscopy Detector, which extended the upper energy range to 8 MeV, all surrounded by a plastic scintillator in active anti-coincidence to veto the large background rates due to cosmic rays and trapped radiation. Sudden increases in the LAD rates triggered a high-speed data storage mode, the details of the burst being read out to telemetry later. Bursts were typically detected at rates of roughly one per day over the 9-year CGRO mission. A strong burst could result in the observation of many thousands of gamma rays within a time interval ranging from ~0.1 s up to about 100 s.

## X-rays

The X-ray/optical composite at left "highlights an ultraluminous X-ray source (ULX) shown in the box. ... The timing and regularity of these outbursts ... make the object one of the best candidates yet for a so-called intermediate-mass black hole. ... Chandra X-ray Observatory [at right] observations of this ULX have provided evidence that its X-radiation is produced by a disk of hot gas swirling around a black hole with a mass of about 10,000 suns." "Chandra observed M74 twice: once in June 2001 and again in October 2001. The XMM-Newton satellite also (a European Space Agency mission) observed this object in February 2002 and January 2003."

## Opticals

"Observations [of 64 neglected double stars] were made with the GRAS002 robotic [optical] telescope located at the Remote Astronomical Society Observatory [at] Mayhill, [New Mexico] NM, USA (http://www.remote-astronomical-society.org/)."
The double stars [were] imaged using a Takahashi Mewlon 300 Dall-Kirkham cassegrainian reflector located at the Remote Astronomical Society Obseervatory in Mayhill, New Mexico."
The Gran Telescopio Canarias (meaning "Canaries Great Telescope"), also known as GranTeCan or GTC, is a 10.4 m (410 in) reflecting telescope at the Roque de los Muchachos Observatory on the island of La Palma, in the Canary Islands of Spain, as of July 2009. The telescope [is] sited on a volcanic peak 2,267 metres (7,438 ft) above sea level. As of 2009, it is the world's largest single-aperture optical telescope.
The GTC began its preliminary observations on 13 July 2007, using 12 segments of its primary mirror, made of Zerodur glass-ceramic by the German company Schott AG. Later the number of segments was increased to a total of 36 hexagonal segments fully controlled by an active optics control system, working together as a reflective unit. Its Day One instrumentation [is the Optical System for Imaging and low Resolution Integrated Spectroscopy] OSIRIS. Scientific observations began properly in May 2009.

## Ultraviolets

"OAO 1 was a solar-cell-powered satellite instrumented to make precision astronomical observations and to measure the absorption and emission characteristics of the stars, planets, nebulae, and the interplanetary and interstellar media from visible to gamma-ray regions. The stabilization system permitted three axes a pointing accuracy of 1 arc minute after the star tracker acquired a guide star. The control system permitted an ultimate pointing accuracy of 0.1 arc second."
"Ultraviolet extinction bumps [in spectra obtained using OAO 2] are investigated in the interstellar extinction curves between 1800 and 3600 A for 36 stars which have (B-V) excesses ranging from 0.03 to 0.55 and are mostly confined to the brighter OB associations distributed along the galactic plane. Each extinction curve is found to have a broad bump which peaks near 2175 A and whose position and profile appear to be constant among all the stars. It is shown that the bump is probably interstellar in origin and that the constancy of its position and shape places such severe restrictions on grain geometrical parameters that classical scattering theory cannot be used to explain the feature unless the dust grains in widely separated regions of space and with very different physical conditions are assumed to have nearly identical size and shape distributions."

## Visuals

What is “the “old-fashioned” spirit of real-time visual astronomy”? “I think everyone can conjure up a mental image of astronomers at every level and place in history, gazing through the eyepieces of their telescopes at sights far away - true visual astronomy.”
At right is an image of the 26-inch Warner & Swasey refracting telescope at the United States Naval Observatory.

## Violets

In 1959 "observations of the spectrum of the planet Venus, with spectrographs of low and high dispersion at the Georgetown College Observatory, show that a wide, continuous absorption band is present in the violet and near-ultraviolet."
The spectra at right show a "[c]omparison between a night sky spectrum obtained in a light polluted site (Asiago Astrophysical Observatory – Italy, upper panel) and a dark site (ESO-Paranal – Chile, lower panel). Spectral line identifications for the main features are traced in red for artificial sources and in blue for the natural ones. The emissions generated by street lighting are clearly visible, mainly in the form of strong lines of Mercury and Sodium, which fall not only in the visible range (500-600nm), but also in the in blue and violet parts of the spectrum."

## Blues

"VERITAS (Very Energetic Radiation Imaging Telescope Array System) is a ground-based gamma-ray instrument operating at the Fred Lawrence Whipple Observatory (FLWO) in southern Arizona, USA. It is an array of four 12m optical reflectors for gamma-ray astronomy in the GeV - TeV energy range. These imaging Cherenkov [a bluish light] telescopes are deployed such that they have the highest sensitivity in the VHE energy band (50 GeV - 50 TeV), with maximum sensitivity from 100 GeV to 10 TeV. This VHE observatory effectively complements the NASA Fermi mission."
The Collaboration between Australia and Nippon for a Gamma Ray Observatory in the Outback, CANGAROO is for very high energy cosmic gamma ray observation by telescope [detecting Cherenkov light]. It is located on the Woomera Prohibited Area in South Australia.

## Cyans

In January 1986, the Voyager 2 spacecraft flew by Uranus at a minimal distance of 107,100 km providing the first close-up images and spectra of its atmosphere. They generally confirmed that the atmosphere was made of mainly hydrogen and helium with around 2% methane. The atmosphere appeared highly transparent and lacking thick stratospheric and tropospheric hazes. Only a limited number of discrete clouds were observed.

## Greens

"In 1999, observations of the Venus nightglow with the Keck I telescope showed that the 5577 Å oxygen green line was a significant feature, comparable in intensity to the terrestrial green line. Subsequent measurements have been carried out at the Apache Point Observatory (APO) [at left] and again at Keck I, confirming the presence of the line with substantially varying intensity."
"[U]nequivocal detections [occurred at McDonald Observatory on 10 nights from 25 June through 17 July 2000] of the O ($^1$S) and O ($^1$D) metastable lines in emission in the cometary [Comet C/1999 S4 (LINEAR)] spectrum. These lines are well separated from any telluric or cometary emission features."

## Yellows

"The lack of long period Cepheids of Population I with P > 45 d in the Galaxy as opposed to the Magellanic Clouds, has fascinated observers and theoreticians for many years."

## Oranges

The Spite plateau (or Spite lithium plateau) is a baseline in the abundance of lithium found in old stars orbiting the galactic halo.
"Lithium depletion through atomic diffusion has been suggested as a solution to the discrepancy between the Spite plateau abundance and the predicted value of the primordial lithium abundance".

## Reds

"The flare was observed by [the commencement of an enormous bright flare was observed at 03:37 UT on 1991 June 4 (K. Yamaguchi, M. Ire, & M. Miyashita 1991, private communication$^5$; Sakurai et al. 1992) with] a 14 cm aperture Hα monochromatic heliograph of the National Astronomical Observatory [Mitaka, Tokyo 181, Japan]."
Visual photographs of Comet West showing red emission from the comet's tail have been taken in early March 1976 at the Munich Public Observatory shown at right.

## Infrareds

The European Space Agency's Herschel Space Observatory has aboard the Photodetector Array Camera and Spectrometer (PACS). "The camera operates in three bands centred on 70, 100, and 160 μm, respectively, and the spectrometer covers the wavelength range between 51 and 220 μm."

## Submillimeters

The "solar submillimeter telescope [(SST) is] at the El Leoncito Observatory located at 2550 m altitude in the Argentina Andes. The SST has a 1.5 m reflector with four 212 GHz and two 405 GHz radiometers operating simultaneously with 5 ms time resolution. The main-beam cluster consists of three 212 GHz beams (about 4 half-power beamwidth) partially overlapping each other and one 405 GHz beam (about 2) in the center of the three".

## Microwaves

"The basic scientific goal of the Planck mission is to measure [cosmic microwave background] CMB anisotropies at all angular scales larger than 10 arcminutes over the entire sky with a precision of ~2 parts per million. The model payload consists of a 1.5 meter off-axis telescope with two focal plane arrays of detectors sharing the focal plane. Low frequencies will be covered by 56 tuned radio receivers sensitive to 30-100 GHz, while high frequencies will be covered by 56 bolometers sensitive to 100-850 GHz."

## Radars

The "Arecibo Observatory in Puerto Rico [is] the world's largest, and most sensitive, single-dish radio telescope."
"The 1,000-foot-diameter (305 meters) Arecibo telescope [... provides] access to state-of-the-art observing for scientists in radio astronomy, solar system radar and atmospheric studies, and the observatory has the unique capability for solar system and ionosphere (the atmosphere's ionized upper layers) radar remote sensing."
It contains the largest curved focusing dish on Earth, giving Arecibo the largest electromagnetic-wave-gathering capacity. The dish surface is made of 38,778 perforated aluminum panels, each measuring about 3 by 6 feet (1 by 2 m), supported by a mesh of steel cables.
The telescope has three radar transmitters, with [EIRP] effective isotropic radiated powers of 20 TW at 2380 MHz, 2.5 TW (pulse peak) at 430 MHz, and 300 MW at 47 MHz. The telescope is a spherical reflector, not a parabolic reflector. To aim the telescope, the receiver is moved to intercept signals reflected from different directions by the spherical dish surface. A parabolic mirror would induce a varying astigmatism when the receiver is in different positions off the focal point, but the error of a spherical mirror is the same in every direction.
The receiver is located on a 900-ton platform which is suspended 150 m (500 ft) in the air above the dish by 18 cables running from three reinforced concrete towers, one of which is 110 m (365 ft) high and the other two of which are 80 m (265 ft) high (the tops of the three towers are at the same elevation). The platform has a 93-meter-long rotating bow-shaped track called the azimuth arm on which receiving antennas, secondary and tertiary reflectors are mounted. This allows the telescope to observe any region of the sky within a forty-degree cone of visibility about the local zenith (between −1 and 38 degrees of declination). Puerto Rico's location near the equator allows Arecibo to view all of the planets in the Solar System, though the round trip light time to objects beyond Saturn is longer than the time the telescope can track it, preventing radar observations of more distant objects.

## Radios

The radio telescope P-2500 (RT 70) - Soviet radio telescope with a mirror diameter of 70 meters - is one of the largest in the world. It is located on the third floor of the Deep Space Communication building on the Black Sea coast near the village of Dairy (Ukraine).
The "La Posta Astro-Geophysical Observatory, shown at left, [is] on a 3,900-foot site in the Laguna Mountains 65 miles east of San Diego. The observatory played a major role in solar radio mapping, studies of environmental disturbances, and development of a solar optical videometer for microwave research. Its 60-foot dish, which could both transmit and receive, was used for important Center research programs in propagation and ionospheric forecasting.

## Superluminals

"For the 1989.29 VLBI observation we simultaneously used the VLA [above center] at 5 GHz in its normal B-configuration synthesis mode to obtain an image of the large scale structure of 3C390.3 with angular resolution of 1.2". We observed the source nearly continuously for 14 hours, except for a 5 min observation of 1803+784 as a phase and amplitude calibrator twice per hour."

## Plasma objects

"To that purpose, we review the current understanding of the prominence as a plasma object and relate it to its surrounding cavity."
"The eclipse photographs [...] belong to the High Altitude Observatory archives."

## Gaseous objects

"BVI images were obtained with an 800 x 800 TI CCD on the Perkins 1.8 m telescope at Anderson Mesa over two nights in 1991 October."
The ""shell" is peculiar in that the gaseous object is a giant filament rather than an intact ring."

## Liquid objects

Condensation "calculations show that spinel-rich chondrules did not crystallize from metastable liquid condensates, and that spinel-rich inclusions are not aggregates of refractory nebular condensates."
The Smithsonian Astrophysical Observatory at right participates in meteorite research. The observatory is now part of the Harvard-Smithsonian Center for Astrophysics.

## Rocky objects

"The formation of Earth-like planets through collisional accumulation of rocky objects within a disk has mainly been explored in theoretical and computational work in which post-collision ejecta evolution is typically ignored$^{1,2,3}$, although recent work has considered the fate of such material$^4$. [...] An important ingredient in understanding the vanishing mid-infrared excess emission toward TYC 8241 2652 1 is the initial state of its disk system. Given an age of ~10 Myr, the star could have been host to either an accreting protoplanetary disk rich in gas and dust or a second-generation debris disk formed from the collisions of rocky objects orbiting the star$^{13}$. [...] the dusty material orbiting TYC 8241 2652 1 is the result of the collisions of rocky objects."
"To determine the age of TYC 8241 2652 1 we obtained high-resolution optical spectra over four epochs from February 2008 to January 2009 with an echelle spectrograph mounted on the Siding Spring Observatory 2.3-m telescope. [...] The spectral type and effective temperature is determined from line ratios$^{28}$ in the Siding Spring Observatory echelle spectra."

## Shelters

For intelligent life forms to survive in conditions above the Earth's atmosphere or even within that atmosphere, often requires protection. This protective gear or mechanisms are made of chemicals.

## Sun

"On April 23, 1978 a system of bright loop prominences was observed at Oslo Solar Observatory, Harestua, on the east limb of the Sun."

## Locations on Earth

The town is generally between 70 m and 100 m above sea level.
The location of the observatory can hardly be considered ideal for astronomical observations, even at the time of its construction. It is at a low elevation in an essentially urban setting of an army town with many nearby buildings that date from the time of its construction.[2] It is very near a road that is lit by streetlights, although this was somewhat ameliorated by a clockwork switch inside the observatory that would turn off the nearest streetlights for about 20 minutes. This clockwork system was upgraded in 1987. As the electricity supply has been removed in 2006, this facility is no longer available. In its current location, the observatory will be an island in a sea of houses and some people fear that it will be targeted by vandals or, perhaps, will have to be protected with high, unsightly fences.
The National Observatory of Athens is 107 m asl.
The new 63 cm telescope in Penteli [is] used extensively by the astronomers of the Institute.
"Research areas of the [Institute of Astronomy and Astrophysics] IAA range from Solar Physics to Cosmology. The IAA also runs the 2.3 m Aristarchos telescope at Helmos Observatory and the 1.2 m telescope at Kryoneri Observatory."

## Neolithic

The base of the Neolithic is approximated to 12,200 b2k.
Whatever religious, mystical or spiritual elements were central to Stonehenge, its design includes a celestial observatory function, which might have allowed prediction of eclipse, solstice, equinox and other celestial events important to a contemporary religion.
“Stonehenge does not occupy a topographic high, but rather a site of intermediate elevation, such that the natural horizon, when viewed from the heel stone, is remarkably even and is sufficiently far away that its elevation above the astronomical horizon is a small angle.”
“All results were registered by Professor Gowland in relation to a datum line [102.8 m] 337.4 feet above sea level.”

## Observation posts

An observation post, temporary or fixed, is any preselected position from which observations are to be made - this may include very temporary installations or even an airborne aircraft.

## Outbuildings

The shapes and sizes, as well as functions, of particular observatories have changed over time.
An instrument, or a collection of them, with outbuildings for such things as control centres, data reduction centers, and maintenance are called observatories, such as radio observatories.

## Domes

Most optical telescopes are housed within a dome or similar structure, to protect the delicate instruments from the elements. Telescope domes have a slit or other opening in the roof that can be opened during observing, and closed when the telescope is not in use. In most cases, the entire upper portion of the telescope dome can be rotated to allow the instrument to observe different sections of the night sky.
The domes of observatories, such as in the image at right, and the objects inside used to observe and control these observatories are made of chemicals.

## Towers

Tuorla is located about 12 kilometres from Turku in the direction of Helsinki. The observatory is at an altitude of 60.6 m above sea level (asl). The tower allows the observatory clear line of sight without being affected by the surrounding trees.

## Control rooms

Def. a room serving as the centre of monitoring a building, controlling an operation etc is called a control room.

## Equatorial rooms

An equatorial room, in astronomical observatories, is the room which contains an equatorial mounted telescope. It is usually referred to in observatory buildings that contain more than one type of instrument: for example buildings with an "equatorial room" containing an equatorial telescope and a "transit room" containing a transit telescope. Equatorial rooms tend to be large circular rooms to accommodate all the range of motion of a long telescope on an equatorial mount and are usually topped with a dome to keep out the weather.

## Laboratories

Housing sensitive instruments on the ground floor may benefit from being “surrounded by thick concrete walls, which offer excellent thermal stability and of course vibration isolation from the dome and external observatory structure.”

## Observation rooms

On the right is an image of the observation room for the 150-Foot Solar Tower Observatory on Mt. Wilson.

## Stairwells

The staircase or stairwell to an observation platform or a telescope provides an excellent spiral wall to exhibit images and photographs from completed and ongoing research.
At right is the spiral staircase to the old viewing room of the United States Naval Observatory.
Left is the staircase for the observation platform at the Munich Public Observatory.

## Warm rooms

“With the increasing use of computers and CCD cameras, it is very advantageous to incorporate a 'warm room' into the observatory structure to keep the computer warmer than ambient air in cool seasons.”

## Libraries

"The Astronomy Library supports programs of study in both astronomy and astrophysics and is used by the Astronomy Department, the Center for Space Physics and the Institute for Astrophysical Research. Named for Professor Michael D. Papagiannis in recognition of his 30 years of service to Boston University, this collection includes books in all areas of the field, current journals, and a comprehensive collection of sky atlases and maps."
The image on the right shows reading tables and a portion of the stacks. The images on the left and center show the main reading rooms of the Cambridge Observatory Library and Van Vleck Observatory Library of Wesleyan University, respectively.

## Machine shops

"Our objective is to design, build, and maintain the highest quality research and teaching instruments, while always keeping finished cost to a minimum and safety to a maximum."
"I asked him where he had it made, he said he made it himself, & when I asked him where he got his tools said he made them himself & laughing added if I had staid for other people to make my tools & things for me... I had never made any thing..."

## Lecture rooms

The Munich Public Observatory "lecture room has 64 seats and a wide range of equipment for presentations: Slide-, video-, LCD- and overhead-projectors and a large screen with the dimension of 3 x 2.5 m. Lectures can be transmitted to our conference room."

## Exhibition halls

"There is a scaled model of the solar system in the 40 square meters sized exhibition hall [of the Munich Public Observatory]. A mini-planetarium demonstrates the orbits of Earth and Moon. With our spatial model the positions of the stars in the universe can be easily understood. Astronomical information is shown on large boards."

## Conference rooms

The Munich Public Observatory "50 square meters sized conference room is equipped for multi-purpose use with a variable number of seats and a bar. We use it for seminars and as a lounge for our club members."

## Planetaria

"In [the Munich Public Observatory] planetarium with 32 seats a Zeiss projector creates an impressive view of the night sky, independent of the weather or time of day, which in nature could only be seen under the best weather conditions. The constellations and the movement of the sun, moon and planets can be clearly demonstrated and these important aspects of the science of astronomy can be easily explained."
At left is the exterior structure for the Minsk planetarium.

## Observation platforms

Both astronomers and the general public who enjoy and support most astronomical observatories take advantage of observation platforms.
"The 300 square meters sized observation platform [at the Munich Public Observatory shown at right] is located at an altitude of 35 meters above street level and provides a splendid view over the city of [Munich] and the Alps. Two telescope domes [and] two smaller huts, housing the large telescopes are located here. In addition to these the visitors can use a series of smaller, portable telescopes."
An airborne observatory is an airplane or balloon with an astronomical telescope. By carrying the telescope high, the telescope can avoid cloud cover, pollution, and carry out observations in the infrared spectrum, above water vapor in the atmosphere which absorbs infrared radiation.
The Gerard P. Kuiper Airborne Observatory (KAO) was a national facility operated by NASA to support research in infrared astronomy. The observation platform was a highly modified C-141A jet transport aircraft with a range of 6,000 nautical miles (11,000 km), capable of conducting research operations up to 48,000 feet (14 km). The KAO was based at the Ames Research Center, NAS Moffett Field, in Sunnyvale, California. It began operation in 1974 as a replacement for an earlier aircraft, the Galileo Observatory, a converted Convair CV-990 (N711NA).
The Stratospheric Observatory for Infrared Astronomy (SOFIA) ... is based on a Boeing 747SP wide-body aircraft that has been modified to include a large door in the aft fuselage that can be opened in flight to allow a 2.5 meter diameter reflecting telescope access to the sky. This telescope is designed for infrared astronomy observations in the stratosphere at altitudes of about 41,000 feet (about 12 km). SOFIA's flight capability allows it to rise above almost all of the water vapor in the Earth's atmosphere, which blocks some infrared wavelengths from reaching the ground. At the aircraft's cruising altitude, 85% of the full infrared range will be available. The aircraft can also travel to almost any point on the Earth's surface, allowing observation from the northern and southern hemispheres.

## Hypotheses

* Radiation astronomy observatories have probably been around as long as hominins have.