Herschel Space Observatory

The **Herschel Space Observatory** was a space observatory built by the European Space Agency (ESA). It was the largest infrared telescope ever put into orbit until the launch of the James Webb Space Telescope. Herschel was named after Sir William Herschel, the discoverer of the infrared spectrum, double stars, and planet Uranus.

The device was sensitive to the far infrared and sub-millimetre short wavebands. It had a single mirror of  in diameter.

The observatory was carried into orbit in May 2009. It was at the second Lagrangian point (L2) of the Earth-Sun system. At these points, 1,500,000 kilometres (930,000 miles) from the Earth, gravity balances, so the object stays in place.

The Herschel Observatory could record ('see') the coldest and dustiest objects in space. For example, dusty galaxies just starting to form new stars. The United States, through NASA, worked with the ESA to build and operate the observatory. It was the fourth 'cornerstone' mission in the ESA science program, along with Rosetta, Planck, and Gaia.

The observatory was designed to investigate four main topics:
- Galaxy formation in the early universe and the evolution of galaxies;
- Star formation and its interaction with the interstellar medium;
- Chemical composition of atmospheres and surfaces of Solar System bodies, including planets, comets and moons;
- Molecular chemistry across the universe.

## Other websites

- ESA Herschel Science Centre
- ESA Information on Herschel
- NASA Herschel website
- ESA Herschel operations page
- ESA video on YouTube
- Cardiff School of Physics and Astronomy: Herschel/SPIRE team

## Infobox (spaceflight/instruments)

- **acronym1**: HIFI
- **name1**: Heterodyne Instrument for the Far Infrared
- **acronym2**: PACS
- **name2**: Photodetector Array Camera and Spectrometer
- **acronym3**: SPIRE
- **name3**: Spectral and Photometric Imaging Receiver


## Infobox (spaceflight)

- **name**: Herschel Space Observatory
- **names list**: Far Infrared and Submillimetre Telescope
- **image**: Herschel Space Observatory.jpg
- **image caption**: Artist's impression of the _Herschel_ spacecraft
- **image size**: 250px
- **mission type**: Space telescope
- **operator**: European Space Agency, ESANASA
- **cospar id**: 2009-026A
- **satcat**: 34937
- **website**: http://www.esa.int/herschel
- **mission duration**: Planned: 3 years
 Final:
- **manufacturer**: Thales Alenia Space
- **payload mass**: Telescope:
- **power**: 1 kW
- **launch rocket**: Ariane 5, Ariane 5 ECA
- **launch site**: Guiana Space Centre,
French Guiana
- **launch contractor**: Arianespace
- **disposal type**: Decommissioned
- **orbit reference**:
()
- **orbit regime**: Lissajous orbit, Lissajous
- **apsis**: helion
- **telescope type**: Ritchey–Chrétien telescope, Ritchey–Chrétien
- **telescope diameter**:
  (primary mirror)
- **telescope focal length**:

- **telescope wavelength**: 55 to 672 µm (far infrared)
- **insignia caption**: ESA astrophysics insignia for _Herschel_
- **insignia size**: 180x180px
- **programme**: **European Space Agency Science Programme#Horizon 2000, Horizon 2000**
- **previous mission**: _Rosetta (spacecraft), Rosetta_
- **next mission**: _Planck (spacecraft), Planck_