Herschel Space Observatory
The Herschel Space Observatory was a space observatory built and operated by the European Space Agency (ESA). It was active from 2009 to 2013, and was the largest infrared telescope ever launched until the launch of the James Webb Space Telescope in 2021. Herschel carries a 3.5-metre (11.5 ft) mirror and instruments sensitive to the far infrared and submillimetre wavebands (55–672 µm). Herschel was the fourth and final cornerstone mission in the Horizon 2000 programme, following SOHO/Cluster II, XMM-Newton and Rosetta.
Model of the Herschel Observatory | |||||||||
| Names | Far Infrared and Submillimetre Telescope | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Mission type | Space telescope | ||||||||
| Operator | ESA / NASA | ||||||||
| COSPAR ID | 2009-026K | ||||||||
| SATCAT no. | 34937 | ||||||||
| Website | www | ||||||||
| Mission duration | Planned: 3 years Final: 4 years, 1 month, 2 days | ||||||||
| Spacecraft properties | |||||||||
| Manufacturer | Thales Alenia Space | ||||||||
| Launch mass | 3,400 kg (7,500 lb) | ||||||||
| Payload mass | Telescope: 315 kg (694 lb) | ||||||||
| Dimensions | 7.5 m × 4.0 m (25 ft × 13 ft) | ||||||||
| Power | 1 kW | ||||||||
| Start of mission | |||||||||
| Launch date | 14 May 2009, 13:12:02 UTC | ||||||||
| Rocket | Ariane 5 ECA | ||||||||
| Launch site | Guiana Space Centre, French Guiana | ||||||||
| Contractor | Arianespace | ||||||||
| End of mission | |||||||||
| Disposal | Decommissioned | ||||||||
| Deactivated | 17 June 2013, 12:25 UTC | ||||||||
| Orbital parameters | |||||||||
| Reference system | L2 point (1,500,000 km / 930,000 mi) | ||||||||
| Regime | Lissajous | ||||||||
| Main telescope | |||||||||
| Type | Ritchey–Chrétien | ||||||||
| Diameter | 3.5 m (11 ft) f/0.5 (primary mirror) | ||||||||
| Focal length | 28.5 m (94 ft) f/8.7 | ||||||||
| Collecting area | 9.6 m2 (103 sq ft) | ||||||||
| Wavelengths | 55 to 672 µm (far infrared) | ||||||||
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ESA astrophysics insignia for Herschel | |||||||||
The observatory was carried into orbit by an Ariane 5 in May 2009, reaching the second Lagrangian point (L2) of the Earth–Sun system, 1,500,000 kilometres (930,000 mi) from Earth, about two months later. Herschel is named after Sir William Herschel, the discoverer of the infrared spectrum and planet Uranus, and his sister and collaborator Caroline Herschel.
The observatory was capable of seeing the coldest and dustiest objects in space; for example, cool cocoons where stars form and dusty galaxies just starting to bulk up with new stars. The observatory sifted through star-forming clouds—the "slow cookers" of star ingredients—to trace the path by which potentially life-forming molecules, such as water, form.
The telescope's lifespan was governed by the amount of coolant available for its instruments; when that coolant ran out, the instruments would stop functioning correctly. At the time of its launch, operations were estimated to last 3.5 years (to around the end of 2012). It continued to operate until 29 April 2013 15:20 UTC, when Herschel ran out of coolant.
NASA was a partner in the Herschel mission, with US participants contributing to the mission; providing mission-enabling instrument technology and sponsoring the NASA Herschel Science Center (NHSC) at the Infrared Processing and Analysis Center and the Herschel Data Search at the Infrared Science Archive.