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GALEX
Galaxy Evolution Explorer (GALEX or Explorer 83 or SMEX-7) was a NASA orbiting space telescope designed to observe the universe in ultraviolet wavelengths to measure the history of star formation in the universe. In addition to paving the way for future ultraviolet missions, the space telescope allowed astronomers to uncover mysteries about the early universe and how it evolved, as well as better characterize phenomena like black holes and dark matter. GALEX was launched on 28 April 2003 for a 29-month primary mission, which was extended three times before the spacecraft was placed into standby mode on 7 February 2012, and decommissioned in June 2013.
The spacecraft was three-axis stabilized, with power coming from four fixed gallium arsenide (GaAs) solar cells which supply nearly 300 watts to the spacecraft. The satellite bus is from Orbital Sciences Corporation based on OrbView 4. The telescope was a 50 cm (20 in) Modified Ritchey–Chrétien with a rotating grism. GALEX used the first ever UV light dichroic beam-splitter flown in space to direct photons to its Near UV (175–280 nanometers) and Far UV (135–174 nanometers) microchannel plate detectors. Each of the two detectors was 65 mm (2.6 in) in diameter. The target orbit was 670 km (420 mi) circular and inclined at 29.00° to the equator.
An air launched Pegasus launch vehicle, launched on 28 April 2003 at 11:59:57 UTC, placed the craft into a nearly circular orbit at an altitude of 697 km (433 mi) and an orbital inclination to the Earth's equator of 29.00°.
The Galaxy Evolution Explorer (GALEX) explored the origin and evolution of galaxies, and the origins of stars and heavy elements over the redshift range of Z between 0 and 2. GALEX conducted an all-sky imaging survey, a deep imaging survey, and a survey of 200 galaxies nearest to the Milky Way galaxy. As well, GALEX performed three spectroscopic surveys over the 135–300 nanometre band. GALEX had a planned 29-month mission, and is a part of the Small Explorer (SMEX) program.
The first observation, taken on 21 May 2003, was in the constellation Hercules, and was dedicated to the crew of the Space Shuttle Columbia. This region was selected because it had been directly overhead the shuttle at the time of its last contact with the NASA Mission Control Center, Houston, Texas.
After its primary mission of 29 months, observation operations were extended. In 2009, one of its detectors, which observed in far-ultraviolet light, stopped functioning. Late in the mission, observations of more intense UV sources were allowed, including the Kepler field.
Observation operations were extended to almost 9 years, with NASA placing it into standby mode on 7 February 2012. NASA cut off financial support for operations of GALEX in early February 2011 as it was ranked lower than other projects which were seeking a limited supply of funding. The mission's life-cycle cost to NASA was US$150.6 million. The California Institute of Technology (Caltech) negotiated to transfer control of GALEX and its associated ground control equipment to the California Institute of Technology in keeping with the Stevenson-Wydler Technology Innovation Act. Under this Act, excess research equipment owned by the U.S. government can be transferred to educational institutions and non-profit organizations. On 17 May 2012, GALEX operations were transferred to Caltech.
On 28 June 2013, NASA decommissioned GALEX. It is expected that the spacecraft will remain in orbit until at least 2068 before it will re-enter the atmosphere.
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GALEX AI simulator
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GALEX
Galaxy Evolution Explorer (GALEX or Explorer 83 or SMEX-7) was a NASA orbiting space telescope designed to observe the universe in ultraviolet wavelengths to measure the history of star formation in the universe. In addition to paving the way for future ultraviolet missions, the space telescope allowed astronomers to uncover mysteries about the early universe and how it evolved, as well as better characterize phenomena like black holes and dark matter. GALEX was launched on 28 April 2003 for a 29-month primary mission, which was extended three times before the spacecraft was placed into standby mode on 7 February 2012, and decommissioned in June 2013.
The spacecraft was three-axis stabilized, with power coming from four fixed gallium arsenide (GaAs) solar cells which supply nearly 300 watts to the spacecraft. The satellite bus is from Orbital Sciences Corporation based on OrbView 4. The telescope was a 50 cm (20 in) Modified Ritchey–Chrétien with a rotating grism. GALEX used the first ever UV light dichroic beam-splitter flown in space to direct photons to its Near UV (175–280 nanometers) and Far UV (135–174 nanometers) microchannel plate detectors. Each of the two detectors was 65 mm (2.6 in) in diameter. The target orbit was 670 km (420 mi) circular and inclined at 29.00° to the equator.
An air launched Pegasus launch vehicle, launched on 28 April 2003 at 11:59:57 UTC, placed the craft into a nearly circular orbit at an altitude of 697 km (433 mi) and an orbital inclination to the Earth's equator of 29.00°.
The Galaxy Evolution Explorer (GALEX) explored the origin and evolution of galaxies, and the origins of stars and heavy elements over the redshift range of Z between 0 and 2. GALEX conducted an all-sky imaging survey, a deep imaging survey, and a survey of 200 galaxies nearest to the Milky Way galaxy. As well, GALEX performed three spectroscopic surveys over the 135–300 nanometre band. GALEX had a planned 29-month mission, and is a part of the Small Explorer (SMEX) program.
The first observation, taken on 21 May 2003, was in the constellation Hercules, and was dedicated to the crew of the Space Shuttle Columbia. This region was selected because it had been directly overhead the shuttle at the time of its last contact with the NASA Mission Control Center, Houston, Texas.
After its primary mission of 29 months, observation operations were extended. In 2009, one of its detectors, which observed in far-ultraviolet light, stopped functioning. Late in the mission, observations of more intense UV sources were allowed, including the Kepler field.
Observation operations were extended to almost 9 years, with NASA placing it into standby mode on 7 February 2012. NASA cut off financial support for operations of GALEX in early February 2011 as it was ranked lower than other projects which were seeking a limited supply of funding. The mission's life-cycle cost to NASA was US$150.6 million. The California Institute of Technology (Caltech) negotiated to transfer control of GALEX and its associated ground control equipment to the California Institute of Technology in keeping with the Stevenson-Wydler Technology Innovation Act. Under this Act, excess research equipment owned by the U.S. government can be transferred to educational institutions and non-profit organizations. On 17 May 2012, GALEX operations were transferred to Caltech.
On 28 June 2013, NASA decommissioned GALEX. It is expected that the spacecraft will remain in orbit until at least 2068 before it will re-enter the atmosphere.