Galaxy Evolution Explorer

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GALEX
GALEX
Type: Space telescope
Country: United StatesUnited States United States
Operator: NASA
COSPAR-ID : 2003-017A
Mission dates
Dimensions: 280 kg
Begin: April 28, 2003, 12:00 UTC
Starting place: Mayport Drop Zone
at 29 ° N, 78.5 ° W
Launcher: Pegasus XL ,
dropped from an L-1011
Flight duration: 10 years, 2 months
Status: Decommissioned on
June 28, 2013 at 19:09 (UTC)
Orbit data
Rotation time : 98.6 min
Orbit inclination : 29.0 °
Apogee height :  697 km
Perigee height :  691 km

GALEX ( Gal axy Evolution Ex plorer or Explorer 83 ) is a space telescope of NASA for the observation of galaxies in the ultraviolet region of the electromagnetic spectrum .

construction

The main mirror from GALEX is approx. 50 centimeters in diameter. The field of view is very large at over 1 °. One detector of the telescope observes in the wavelength range from 135 to 175 nm, the other in the range from 175 to 280 nm.

Mission under the direction of NASA

On April 28, 2003, GALEX was brought into Earth orbit at an altitude of approx. 695 km with an orbital inclination of 29 ° using an aircraft-based Pegasus rocket . The starting area was the Mayport Drop Zone at 29 ° north and 78.5 ° west off the coast of Florida .

The originally planned mission duration of 29 months could be exceeded. In 2006 the NASA Senior Review Panel recommended extending the mission. In 2005 to 2007 and 2009, short circuits led to failures of the detector that observed the far ultraviolet range. As of 2009, the damage could no longer be repaired, as happened in the past, so that only one of the detectors can now be used.

In 2007, with the help of the now failed detector, a 13 light-year long tail was discovered behind the star Mira .

Mission under the direction of Caltech

On February 7th, 2012, GALEX was switched to stand-by mode in order to be switched off for good in 2012. However, negotiations were ongoing as to whether NASA would transfer the Galaxy Evolution Explorer to the California Institute of Technology (Caltech), which wanted to continue operating the satellite. This was made possible by the Stevenson-Wydler Technology Innovation Act , but has never been done before with spacecraft in space.

After NASA lent (not transferred) GALEX to Caltech on May 14, 2012 in order to continue to use it for three years, GALEX was initially not switched off. Caltech wants to complete the mapping of the UV sky with GALEX in the three years. Together with other institutes, Caltech bears the operating costs of USD 100,000 per month. These are incurred by Orbital Sciences , which built and operates the satellite as prime contractor. However, NASA remains the owner of GALEX, which could work for another 12 years. In 2013, GALEX discovered a tidal dwarf galaxy formed by the interaction of NGC 6872 with its satellite galaxy NC 4790.

GALEX's extended mission ended on June 28, 2013 with the shutdown of the satellite. It is expected to burn up in about 65 years.

GALEX preparing to launch
Image of the comet-like tail of the star Mira

Web links

Commons : GALEX  - collection of images, videos and audio files

Individual evidence

  1. ↑ GALEX in the NSSDCA Master Catalog , accessed on September 20, 2012 (English).
  2. ↑ GALEX status update. November 27, 2007, accessed July 7, 2010 .
  3. ↑ GALEX status update. December 2, 2009, accessed July 7, 2010 .
  4. ↑ GALEX Status Update - Space Telescope Moves on with One Detector. April 9, 2007, accessed July 7, 2010 .
  5. ^ Science @ NASA: A Star with a Comet's Tail. April 15, 2007, accessed July 7, 2010 .
  6. ↑ Ralph-Mirko Richter: GALEX space telescope is in standby mode in Raumfahrer.net, date: February 8, 2012, accessed: February 10, 2012
  7. ↑ NASA / JPL / California Institute of Technology: NASA's Galaxy Evolution Explorer in Standby Mode , date: February 7, 2012, accessed: February 10, 2012.
  8. ↑ Stephen Clark: NASA, Caltech mull over unique satellite donation in Spaceflight Now Date: February 10, 2012, accessed: February 11, 2012.
  9. ↑ Stephen Clark: Galaxy-hunting telescope to live on with private funding in Spaceflight Now, date: May 16, 2012, accessed: May 18, 2012.
  10. ↑ NASA Lends Galaxy Evolution Explorer to Caltech. California Institute of Technology, May 15, 2012, accessed September 20, 2012 .
  11. ↑ Ralph-Mirko Richter: News from GALEX in Raumfahrer.net, February 17, 2013, accessed: February 18, 2013.
  12. ↑ Caltech: NASA's GALEX Reveals the Largest-Known Spiral Galaxy. Accessed January 10, 2013, February 18, 2013.
  13. ↑ Ralph-Mirko Richter: The GALEX mission has ended in Raumfahrer.net, June 30, 2013, accessed: June 30, 2013.
  14. ↑ JPL: NASA Decommissions Its Galaxy Hunter Spacecraft. Accessed June 28, 2013, June 30, 2013.