GALEX
GALEX (Galaxy Evolution Explorer or Explorer 83) is a space telescope of NASA for observing galaxies in ultraviolet region of the electromagnetic spectrum.
Construction
The primary mirror of GALEX has about 50 centimeters in diameter. The field of view is very large with about 1 °, and therefore had to be paid very close attention to the form in the production of the mirror. A detector of the telescope observed in the wavelength range 135-175 nm, and the other in the range of 175 to 280 nm
Mission, headed by NASA
GALEX was launched on 28 April 2003 with an airborne Pegasus rocket into an orbit at about 695 km altitude with an inclination of 29 °. Starting area was the Mayport Drop Zone at 29 ° North and 78.5 ° West29 - 78.5 off the coast of Florida.
The originally planned mission duration of 29 months could be exceeded. 2006 recommended the NASA Senior Review Panel, to extend the mission. 2005 to 2007 and 2009, there was due to short circuits to failures of the detector which observed the far ultraviolet region. As of 2009, the damage could not remember what happened in the past will be corrected, so will now continue to work with only one of the detectors.
Mission led by the Caltech
On February 7, 2012 GALEX was switched to stand -by mode to be shut down permanently in 2012. However, negotiations took place regarding whether the NASA Galaxy Evolution Explorer to to the California Institute of Technology (Caltech ) above is that the satellite would operate on. This was made possible by the Stevenson - Wydler Technology Innovation Act, but has not previously been made with spacecraft in space.
After the NASA GALEX has awarded 14 May 2012 at the Caltech (not suitable ) to be used by this three years on, GALEX will not shut down. The Caltech intends to complete in three years with the mapping of the GALEX UV sky. The Caltech carries with other institutes operating costs of $ 100,000 per month. These fall in to Orbital Sciences, which built the satellite prime contractor and operates it. However, NASA retains ownership of GALEX, might still work 12 years. 2013 GALEX discovered a tidal dwarf galaxy, which is caused by the interaction of NGC 6872 with its satellite galaxy NC 4790.
The extended mission GALEX ended on June 28, 2013 with the shutdown of the satellite. He is expected to burn up in about 65 years.