astronomical survey


An astronomical survey is a general
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image An SAR radar image acquired by the SIR-C/X-SAR radar on board the Space Shuttle Endeavour shows the Teide volcano. The city of Santa Cruz de Tenerife is visible as the purple and white area on the lower right edge of the island. Lava flows ...

of a region of the
sky The sky is the panorama obtained from observing the universe The universe ( la, universus) is all of space and time and their contents, including planets, stars, galaxy, galaxies, and all other forms of matter and energy. The Big Bang th ...

that lacks a specific observational target. Alternatively, an astronomical survey may comprise a set of many images or spectra of objects that share a common type or feature. Surveys are often restricted to one band of the
electromagnetic spectrum The electromagnetic spectrum is the range of frequencies Frequency is the number of occurrences of a repeating event per unit of time A unit of time is any particular time Time is the indefinite continued sequence, progress of existe ...

electromagnetic spectrum
due to instrumental limitations, although multiwavelength surveys can be made by using multiple detectors, each sensitive to a different bandwidth. Surveys have generally been performed as part of the production of an
astronomical catalog Astronomy (from el, ἀστρονομία, literally meaning the science that studies the laws of the stars) is a natural science that studies celestial objects and phenomena. It uses mathematics Mathematics (from Ancient Greek, Gr ...
. They may also search for
transient astronomical eventA transient astronomical event, often shortened by astronomer An astronomer is a scientist in the field of astronomy who focuses their studies on a specific question or field outside the scope of Earth. They observe astronomical objects such as st ...
s. They often use wide-field
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Scientific value

Sky surveys, unlike targeted observation of a specific object, allow astronomers to catalog celestial objects and perform statistical analyses on them without making prohibitively lengthy observations. In some cases, an astronomer interested in a particular object will find that survey images are sufficient to make telescope time entirely unnecessary. Surveys also help astronomers choose targets for closer study using larger, more powerful telescopes. If previous observations support a hypothesis, a telescope scheduling committee is more likely to approve new, more detailed observations to test it. The wide scope of surveys makes them ideal for finding foreground objects that move, such as asteroids and comets. An astronomer can compare existing survey images to current observations to identify changes; this task can even be performed automatically using
image analysis Image analysis or imagery analysis is the extraction of meaningful information from image File:TEIDE.JPG, An Synthetic aperture radar, SAR radar imaging, radar image acquired by the SIR-C/X-SAR radar on board the Space Shuttle Endeavour sho ...
software. Besides science, these surveys also detect
potentially hazardous object is listed as a potentially hazardous near-Earth asteroid, yet poses no immediate threat to Earth. ( Radar image taken by GDSCC in 1996.) A potentially hazardous object (PHO) is a near-Earth object – either an asteroid or a comet – with an ...
s. Similarly, images of the same object taken by different surveys can be compared to detect
transient astronomical eventA transient astronomical event, often shortened by astronomer An astronomer is a scientist in the field of astronomy who focuses their studies on a specific question or field outside the scope of Earth. They observe astronomical objects such as st ...
s such as variable stars.

List of sky surveys

* Optical **
Hipparchus Hipparchus of Nicaea (; el, Ἵππαρχος, ''Hipparkhos'';  BC) was a Greek astronomer, geographer, and mathematician. He is considered the founder of trigonometry, but is most famous for his incidental discovery of precession of the ...
- created the first known star catalogue with more than 850 stars. The data was incorporated into the
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along with the first list of
stellar magnitudes
stellar magnitudes
and was the primary astronomical reference until modern times, 190-120 BC. **
Astrographic Catalogue The Carte du Ciel (literally, 'Map of the Sky') and the Astrographic Catalogue (or Astrographic Chart) were two distinct but connected components of a massive international astronomical project, initiated in the late 19th century, to catalogue and ...
- first international astronomical survey of the entire sky. The survey was performed by 18 observatories using over 22,000 photographic plates. The results have been the basis of comparison for all subsequent surveys, 1887-1975. **
Catalina Sky Survey Catalina Sky Survey (CSS; obs. code: 703) is an astronomical survey to discover comets and asteroids. It is conducted at the Steward Observatory's Catalina Station, located near Tucson, Arizona, in the United States. CSS focuses on the search f ...

Catalina Sky Survey
- an astronomical survey to discover comets and asteroids. **
Pan-Andromeda Archaeological Survey Pan-Andromeda Archaeological Survey (PAndAS) is a large-scale astronomical survey using the Canada-France-Hawaii Telescope. The survey is exploring the structure and content of the Andromeda Galaxy (M31) and its neighbour, the Triangulum Galaxy (M3 ...
** National Geographic Society – Palomar Observatory Sky Survey (NGS–POSS) – survey of the northern sky on photographic plates, 1948–1958 ** CfA Redshift Survey – A program from Harvard-Smithonian Center for Astrophysics. It began in 1977 to 1982 then from 1985 to 1995. ** Digitized Sky Survey – optical all-sky survey created from digitized photographic plates, 1994 ** 2dF Galaxy Redshift Survey (2dfGRS) – redshift survey conducted by the Anglo-Australian Observatory between 1997 and 2002 ** Sloan Digital Sky Survey (SDSS) – an optical and spectroscopic survey, 2000–2006 (first pass) ** Photopic Sky Survey – a survey with 37,440 individual exposures, 2010–2011. ** DEEP2 Redshift Survey (DEEP2) – Used Keck Telescopes to measure redshift of 50,000 galaxies ** VIMOS-VLT Deep Survey (VVDS) – Franco-Italian study using the Very Large Telescope at Paranal Observatory ** Palomar Distant Solar System Survey (PDSSS) ** WiggleZ Dark Energy Survey (2006–2011) used the Australian Astronomical Observatory ** Dark Energy Survey (DES) is a survey about one-tenth of the sky to find clues to the characteristics of dark energy.- ** Calar Alto Legacy Integral Field Area Survey (CALIFA) – a spectroscopic survey of galaxies ** SAGES Legacy Unifying Globulars and GalaxieS Survey, SAGES Legacy Unifying Globulars and GalaxieS (SAGES Legacy Unifying Globulars and GalaxieS Survey (SLUGGS) survey – a near-infrared spectro-photometric survey of 25 nearby early-type galaxies (2014) ** LAMOST, Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) – an extra-galactic and stellar spectroscopic survey ** The INT Photometric H-Alpha Survey, IPHAS and VPHAS+ – surveys of the Galactic bulge and inner disk using the Isaac Newton Telescope (north) and VLT Survey Telescope (south) in u, g, r, Hα, and i bands, 2003–present ** Pan-STARRS – a proposed 4-telescope large-field survey system to look for transient and variable sources ** Optical Gravitational Lensing Experiment (OGLE) – large-scale variability sky survey (in I and V bands), 1992–present ** Dark Energy Spectroscopic Instrument#DESI Legacy Imaging Surveys, DESI Legacy Imaging Surveys (Legacy Surveys) - large imaging survey of the extragalactic sky, in three bands and covering one third of the sky, 2013–present * Infrared ** IRAS, Infrared Astronomical Satellite did an all sky survey at 12, 25, 60, and 100 μm, 1983 ** 2MASS, The 2-micron All-Sky Survey (2MASS), a ground-based all sky survey at J, H, and Ks bands (1.25, 1.65, and 2.17 μm) 1997–2001 ** Akari (Astro-F) a Japanese mid and far infrared all-sky survey satellite, 2006–2008 ** WISE mission, Wide-field Infrared Survey Explorer (WISE) was launched in December 2009 to begin a survey of 99% of the sky at wavelengths of 3.3, 4.7, 12, and 23 μm. The telescope is over a thousand times as sensitive as previous infrared surveys. The initial survey, consisting of each sky position imaged at least eight times, was completed by July 2010. ** UKIRT Infrared Deep Sky Survey (UKIDSS) – a collection of ground based northern hemisphere surveys (GPS, GCS, LAS, DXS, UDS) using the WFCAM camera on UKIRT, some wide and some very deep, in Z, Y, J, H, & K bands 2005– ** VISTA (telescope), VISTA public surveys – a collection of ground based southern hemisphere surveys (Vista Variables in the Via Lactea, VVV, VMC, VHS, VIKING, VIDEO, UltraVISTA), of various areas and depths, in Z, Y, J, H, & Ks bands, 2009–present ** SCUBA-2 All Sky Survey * Radio **HIPASS – Radio survey, the first blind hydrogen line, HI survey to cover the entire celestial hemisphere, southern sky. 1997–2002 ** Ohio Sky Survey – Over 19,000 radio sources at 1415 MHz. 1965–1973. ** NRAO VLA Sky Survey, NVSS – Survey at 1.4 GHz mapping the sky north of −40 deg ** Faint Images of the Radio Sky at Twenty-Centimeters, FIRST – Survey to look for faint radio sources at twenty cms. ** Sydney University Molonglo Sky Survey, SUMSS - Survey at 843 MHz, mapping the sky south of -30 deg with similar sensitivity and resolution to the northern NVSS ** PALFA Survey – On-going 1.4 GHz survey for radio pulsars using the Arecibo Observatory. ** GALEX Arecibo SDSS Survey GASS designed to measure the neutral hydrogen content of a representative sample of ~1000 massive, galaxies ** C-Band All Sky Survey, C-BASS – On-going 5 GHz all sky survey to aid in the subtraction of galactic foregrounds from maps of the Cosmic Microwave Background ** Evolutionary Map of the Universe, EMU – A large radio continuum survey covering 3/4 of the sky, expected to discover about 70 million galaxies ** Giant Metrewave Radio Telescope, GMRT - The Giant Metrewave Radio Telescope's TGSS ADR mapped the sky at 150 MHz. **High Time Resolution Universe, HTRU – A pulsar and radio transients survey of the northern and southern sky using the Parkes Radio Telescope and the Effelsberg telescope. * Gamma-ray ** Fermi Gamma-ray Space Telescope, formerly referred to as the "Gamma-ray Large Area Space Telescope (GLAST)." 2008–present; the goal for the telescope's lifetime is 10 years. * Multi-wavelength surveys ** Galaxy And Mass Assembly survey, GAMA – the Galaxy And Mass Assembly survey combines data from a number of ground- and space-based observatories together with a large redshift survey, performed at the Anglo-Australian Telescope. The resulting dataset aims to be a comprehensive resource for studying the physics of the galaxy population and underlying mass structures in the recent universe. ** Great Observatories Origins Deep Survey, GOODS – The Great Observatories Origins Deep Survey. ** COSMOS – The Cosmic Evolution Survey ** (The latter two surveys are joining together observations obtained from space with the Hubble Space Telescope, the Spitzer Space Telescope, the Chandra X-ray Observatory and the XMM-Newton satellite, with a large set of observations obtained with ground-based telescopes). ** Atlas 3d survey, Atlas 3d Survey – sample of 260 galaxies for the Astrophysics project. * Planned ** Vera C. Rubin Observatory – a proposed very large telescope designed to repeatedly survey the whole sky that is visible from its location ** ASKAP HI All Sky Survey (WALLABY) – PI Bärbel Koribalski

Surveys of the Magellanic Clouds

* MCELS (Magellanic Cloud Emission-line Survey) * The Magellanic Clouds Photometric Survey – UBVI (optical) * Deep Near Infrared Survey (DENIS) – near-IR

See also

* See astronomical catalogue for a more detailed description of astronomical surveys and the production of astronomical catalogues * Redshift surveys are astronomical surveys devoted to mapping the cosmos in three dimensions * :astronomical catalogues—List of astronomical catalogues on Wikipedia * Astrograph for a type of instrument used in Astronomical surveys. * Timeline of astronomical maps, catalogs, and surveys


{{Authority control Astronomical surveys, Astronomical imaging Observational astronomy Works about astronomy, Survey