Wide-Field Infrared Survey Explorer
WISE | |
---|---|
Type: | Space telescope |
Country: | United States |
Operator: | NASA |
COSPAR-ID : | 2009-071A |
Mission dates | |
Dimensions: | 661 kg |
Begin: | December 14, 2009, 14:09 UTC |
Starting place: | Vandenberg SLC-2W |
Launcher: | Delta 7320-10 D347 |
Status: | in operation |
Orbit data | |
Rotation time : | 95.0 min |
Orbit inclination : | 97.5 ° |
Apogee height : | 522 km |
Perigee height : | 515 km |
Wide-field Infrared Survey Explorer ( WISE , planned as a Next Generation Sky Survey, NGSS ) is an unmanned space telescope of NASA , which the entire sky in four from January 2010 wavelength bands in the mid-infrared range by scrutinized . After the successful launch, it was also named Explorer 92 . It was decommissioned in February 2011, but reactivated in the fall of 2013 to continue searching for asteroids. After the end of the mission was initially announced for December 2018, it will now be continued.
tasks
The objects that WISE examined included
- Asteroids and other objects of the solar system . WISE aims to find all asteroids in the main belt that are more than 3 km in diameter
- Cool and faint stars , including the stars closest to the Sun and brown dwarfs
- If the hypothetical star Nemesis had been a brown dwarf, WISE would have discovered it.
- Young stars in the Milky Way and dust disks around stars that have already evolved
- The most luminous galaxies and infrared galaxies .
Goals and skills go beyond those of the failed Wide Field Infrared Explorer mission. The WISE sky survey is around a hundred times more sensitive than the IRAS and Akari surveys at comparable wavelengths and thus provides an important basis for many future studies.
construction
WISE was built by Ball Aerospace and had a takeoff weight of 661 kg. It requires 301 watts of electrical power, which is supplied by a solar cell field with 551 watts maximum power. The WISE telescope has a diameter of 40 cm, its optics and detectors were cooled by a cryostat with solid hydrogen . It was observed at four wavelength bands around 3.4; 4.6; 12 and 22 μm. After the coolant has been used up, the images at 12 μm are dominated by thermal noise; the 22 μm detector was switched off.
Mission history
Start and first survey
The launch took place on December 14, 2009 at 2:09:33 pm UTC with a Delta II 7320-10C rocket from Vandenberg Air Force Base . The 525 km high orbit is synchronous with the sun . WISE always looks away from the earth and moves uniformly across the sky, but a movable deflecting mirror freezes the 47 '× 47' field of view for a few seconds on the detectors with 1024 × 1024 picture elements each. On December 29, 2009, the protective cap of the telescope was blown off. The first images of the mission were released on January 6, 2010 after WISE was fully calibrated. In the second half of July 2010, WISE completed the first sky survey, for which it took 1.3 million images within half a year.
Second NEOWISE survey and shutdown
On October 5, 2010 it was announced that after 1.5 times the sky had been surveyed, the hydrogen had evaporated and the telescope had therefore warmed to −203 ° C. The mission was continued under the name NEOWISE until January 2011, as the sensors for the two shorter wavelengths still function satisfactorily even at the higher temperature. The second sky survey has been completed, examining asteroids and comets in our solar system. On February 17, 2011, the transmitter was switched off by WISE and the satellite was put into an idle state, from which it could be woken up again for further use if the appropriate funding was available.
reactivation
In August 2013, NASA announced that it would reactivate WISE to track down asteroids for three years. However, WISE was not operational again until several months later, as the telescope first had to cool down and then be calibrated. This mission also bore the project name NEOWISE . After WISE had cooled down to less than −200 ° C at the end of December 2013, further observations began as part of the NEOWISE mission. On December 29, 2013, the space telescope discovered a previously unknown, near-Earth object , the asteroid 2013 YP139 . The NEOWISE project achieved greater awareness through the discovery of comet C / 2020 F3 (NEOWISE) in March 2020, which was named after it.
AllWISE catalog
Within the primary mission, the data of almost 750 million cosmic objects were recorded and published as part of the AllWISE catalog . In analyzing this data, a group from the Jet Propulsion Laboratory discovered around 2.5 million previously unknown, super-massive and active black holes . Furthermore, star islands enveloped by clouds of dust could be detected, the brightness of which is higher than that of our Milky Way and represents an unknown class of galaxies. However, they can only be detected indirectly, as their visible spectrum is shielded by the dust.
The survey also revealed the discovery of 3,525 previously unknown stars and brown dwarfs, which are located within 500 light years of our solar system. In addition, tens of thousands of asteroids and over 20 comets in our solar system have been discovered using the data from WISE. When searching for a large planet X , it failed to detect a planet the size of Jupiter within 26,000 AU of the Sun. The probability of the hypothetical star Nemesis also fell - due to the large and extensive data base .
In March 2015, NASA published the raw data (approx. 2.5 million image sets) from December 13, 2013 to December 13, 2014. The data contain over 10,000 objects in the solar system, 129 of which were newly discovered. There are 39 near-earth objects alone. The data also contains over 10 billion measurements of background objects.
The special catalog AllWISE AGN was also published in 2015 , which is based on the AllWISE catalog from 2013 and specializes in active galactic nuclei (AGN) .
Web links
- University of California at Berkeley: Official project page at the Space Sciences Laboratory (English)
- JPL: WISE website of JPL (English)
- JPL: WISE Press Kit from NASA (English; PDF; 2.1 MB)
- JPL: WISE Fact Sheet (English; PDF; 297 kB)
- IRSA: Wide-field Infrared Survey Explorer (WISE) (English)
Individual evidence
- ↑ Chris Peat: WISE - Orbit. In: Heavens Above. August 6, 2012, accessed August 8, 2012 .
- ↑ Wide-Field Infrared Survey Explorer in the NSSDCA Master Catalog , accessed November 13, 2013.
- ^ The Near Earth Object Wide-field Infrared Survey Explorer (NEOWISE) Science Data Center: The NEOWISE Project. Retrieved March 7, 2019 .
- ↑ To Avalanche of Dark Asteroids . NASA Science, March 26, 2010
- ↑ Launch PRESS KIT / DECEMBER 2009 Wide-field Infrared Survey Explorer. (PDF; 2.1 MB) NASA, December 2009, accessed on October 9, 2010 (English).
- ↑ Amanda K. Mainzer, et al .: Preliminary Design of The Wide-Field Infrared Survey Explorer (WISE) , p. 1: “The single WISE instrument consists of a 40 cm diamond-turned aluminum afocal telescope, a two-stage solid hydrogen cryostat, a scan mirror mechanism, and reimaging optics giving 5 ″ resolution (full-width-half-maximum). “ arxiv : astro-ph / 0508246 ; WISE solid hydrogen cryostat design overview , bibcode : 2005SPIE.5904..357N ; NASA's WISE cryostat , accessed February 21, 2011
- ^ Mission Status Center. Spaceflight Now, December 14, 2009, accessed December 14, 2009 .
- ↑ a b NASA's WISE Space Telescope Jettisons its cover NASA December 29, 2009
- ↑ WISE observatory sheds lens cap and takes in starlight spaceflightnow, December 29, 2009
- ↑ Stefan Deiters: WISE First sky survey completed. Astrones.com, July 20, 2010, accessed October 9, 2010 .
- ↑ NASA's WISE Mission Warms up but Keeps Chugging Along. NASA, October 4, 2010, accessed October 9, 2010 .
- ↑ NASA's NEOWISE Completes Scan for Asteroids and Comets
- ↑ WISE - News & Events. Retrieved March 11, 2012 .
- ↑ NASA reactivates space telescope for asteroid search. ORF, August 22, 2013, accessed on December 13, 2013 .
- ↑ The Neowise Project neowise.ipac.caltech.edu
- ↑ Stephen Clark: WISE telescope approved for three-year asteroid survey. Spaceflight Now, August 22, 2013, accessed November 13, 2013 .
- ↑ Surprise Picture for WISE's Fourth Anniversary. JPL, December 12, 2013, accessed December 13, 2013 .
- ↑ Günther Glatzel: NEOWISE is working again in Raumfahrer.net, Date: December 21, 2013, Accessed: December 24, 2013. December 2013
- ↑ "Neowise": Reactivated telescope tracks asteroids spiegel.de, accessed on January 9, 2014
- ↑ Wide-Field Infrared Survey Explorer in the Small-Body Database of the Jet Propulsion Laboratory .
- ↑ The AllWISE Data Release November 13, 2013. November 13, 2013, accessed July 15, 2018 .
- ↑ Space telescope finds millions of black holes. Spiegel Online, August 30, 2012, accessed August 30, 2012 .
- ↑ a b Ralph-Mirko Richter: WISE: No Planet X in the Outer Solar System in raumfahrer.net, Date: March 11, 2014, Accessed: March 14, 2014
- ↑ Whitney Clavin and JD Harrington: NASA's WISE Survey Finds Thousands of New Stars, But No 'Planet X' , JPL, Date: March 7, 2014, Accessed: March 14, 2014
- ↑ NASA / JPL-Caltech : NASA Asteroid Hunter Spacecraft Data Available to Public . Press release from March 26, 2015.
- ↑ ALLWISEAGN - AllWISE Catalog of Mid-IR AGNs. Retrieved July 15, 2018 .