The Odin earth observation satellite developed by OHB Sweden is a technical marvel and meanwhile the second oldest satellite in the ESAs (European Space Agency) Third Party Missions (TPM) family. The satellite continues to reliably collect valuable data, meaning that Odin is now celebrating its 18th birthday in orbit on February 20, 2019. The mission Odin proves the necessity of taking good care of a system and the importance of having long term trends concerning climate changes. Since its launch on February 20, 2001, the satellite has orbited the Earth around 98,000 times.
Named after the father of gods in Nordic mythology, Odin initially combined two scientific functions. On the one hand, it provided data on star formation on its 600 km long solar-synchronous orbit around the earth, while on the other it explored the mechanisms causing the depletion of the ozone layer in the earth’s atmosphere. Odin was initiated as an international mini-satellite mission lead-managed by Sweden and in cooperation with Canada, France and Finland. Since May 2007, Odin has been a third-party joint mission with the European Space Agency ESA and is now primarily collecting data on the state of the atmosphere, providing us with important information for modelling purposes about the climate changes that threaten us. Odin is the second oldest satellite within the ESAs TPM group. The data from these missions is distributed under specific agreements with the owners or operators of the mission, following the ESA Data Policy.
Developed in Sweden, now in Orbit
Odin is the fifth scientific research satellite developed in Sweden. When the Odin project was still in its infancy, atmospheric researchers discovered that they could use the same instruments to measure the atmosphere as astronomers do for space exploration. So aeronomists and astronomers began to work together. In the Odin project, aeronomists are primarily interested in the distribution of water, chlorine monoxide and ozone. Astronomers for their part are particularly concerned with water and oxygen molecules (O2) in space. The astronomical objectives and the key scientific questions relate to star formation processes, interstellar chemistry and the atmospheric ozone balance.
Odin is still being operated by OHB Sweden. Based in Kista, Sweden, Stefan Lundin is Odin’s project manager. His duties include liaising with the Odin Control Centre OCC in Esrange in Sweden, various scientists and representatives of the government authorities. Odin CC handles the daily work of Odin having several contacts each day. “I run Odin Mission Control, which is based in Stockholm, together with a colleague. Among other things, we are responsible for validating and long term planning, troubleshooting, preparing the scientific roadmap and reporting to the scientists and authorities involved. Sometimes we also adapt to a new situation and change a sequence of commands to respond better to a particular situation. At the same time, we are in close contact with the OCC, which communicates with the satellite several passes per day. We are also responsible for the software both on board the satellite and at the control centers. But fortunately, software changes are made only in rare cases,” says Stefan Lundin.
Two-in-one: Odin addressing astronomy and aeronomy requirements
The main instrument aboard Odin is a radiometer, i.e. a detector for measuring irradiance, with a telescope suitable for both astronomy and aeronomy missions. The radiometer essentially operates in frequency ranges between 486 and 580 GHz and at 119 GHz.
For the aeronomy mission, the payload has been supplemented with a spectrograph, an optical instrument called OSIRIS (Optical Spectrograph and Infrared Imaging System) that breaks down light of different wavelengths into its spectrum and registers this spectrum using suitable detectors.
We are proud that we have accomplished what we promised the scientists.
Odin is able to switch between astronomy and aeronomy mode. It can “stare” at astronomical targets with high precision for hours or alternatively scan the earth’s atmosphere at different speeds at an altitude of 10 to 120 km, 40 times per orbit. “We are proud that we have accomplished what we promised the scientists, ” says Stefan Lundin.