Astronomical survey

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Composite image of the GOODS-South field, result of a deep survey using two of the four giant 8.2-metre telescopes composing ESO's Very Large Telescope.
Gamma-ray pulsars detected by the Fermi Gamma-ray Space Telescope.

An astronomical survey is a general map or image of a region of the sky which lacks a specific observational target. Alternatively, an astronomical survey may comprise a set of many images or spectra of objects which share a common type or feature. Surveys are often restricted to one band of the electromagnetic spectrum due to instrumental limitations, although multiwavelength surveys can be made by using multiple detectors, each sensitive to a different bandwidth.[citation needed] Surveys have generally been performed as part of the production of an astronomical catalogue.

Scientific value[edit]

Sky surveys, unlike targeted observation of a specific object, allow astronomers to catalogue 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 entirely obviate the need for telescope time.

Surveys also help astronomers obtain observation time on larger, more powerful telescopes. If the astronomer can show a telescope scheduling committee that previous observations support his hypothesis, he is more likely to be given a chance to make more detailed observations.

The wide scope of surveys makes them ideal for astronomers searching for moving foreground objects such as asteroids and comets. An astronomer can compare existing survey images to current observations to locate targets which are in motion; this task can even be performed automatically using image analysis software. Similarly, images of the same object taken by different surveys can be compared to detect transient events such as variable stars.[1]

List of sky surveys[edit]

  • 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.
  • Planned
    • Pan-STARRS - a proposed 4-telescope large-field survey system to look for transient and variable sources
    • Large Synoptic Survey Telescope - a proposed very large telescope designed to repeatedly survey the whole sky that is visible from its location

Surveys of the Magellanic Clouds[edit]

Further information[edit]

Notes[edit]

  1. ^ Gay, Dr. Pamela; Cain, Fraser (26 May 2008). "Episode #90: The Scientific Method". Astronomy Cast (Podcast). Retrieved 16 Dec 2009. 
  2. ^ Risinger, Nick. "Phototopic Sky Survey". Retrieved 12 May 2011. 
  3. ^ Associated Press (12 May 2011). "Amateur Photographer Links 37,000 Pics in Night-Sky Panorama". Fox News. Retrieved 13 May 2011. 
  4. ^ "WiggleZ Dark Energy Survey | Home". Wigglez.swin.edu.au. Retrieved 2014-03-03. 
  5. ^ "darkenergysurvey.org". darkenergysurvey.org. Retrieved 2014-03-03. 
  6. ^ "The VLA FIRST Survey". Sundog.stsci.edu. 2008-07-21. Retrieved 2014-03-03. 
  7. ^ "The GALEX Arecibo SDSS Survey". Mpa-garching.mpg.de. Retrieved 2014-03-03. 
  8. ^ gama-survey.org
  9. ^ "GAMA: towards a physical understanding of galaxy formation". Astronomy & Geophysics. Adsabs.harvard.edu. 
  10. ^ "Atlas3D Survey". Astro.physics.ox.ac.uk. Retrieved 2014-03-03.