Spektr-UF (Spektr-UV, SUV, World Space Observatory Ultraviolet, WSO-UV) (original) (raw)

Spektr-UF [Lavochkin]

Spektr-UF (also known as Spektr-UV or SUV) is a UV space observatory mission. The mission is led by Russia, but involves multiple international partners. The mission is also known as World Space Observatory Ultraviolet (WSO-UV).

The Spektr-UF project is led by Russia (Roskosmos) with international cooperation including three basic participants: Russia (provides the telescope, spacecraft, launch facilities, ground segment), Spain (ISSIS, ground segment) and Germany (spectrographs).

Originally the satellite was to be built on the Spektr bus, a derivative of the Prognoz-EW-Bus and to be launched on a Proton-K Blok-DM-2 booster, but budget problems have forced a redesign. Now it will be based on the smaller Navigator bus and was to be launched on a Zenit-3F combination.

The main instrument is the T-170M 1.7-meter Ritchey-Chretien telescope, a lighter version of the originally planned T-170 telescope. It was to be equipped with three instruments:

• HIRDES (High-Resolution Double Echelle Spectrograph): R~55000 spectroscopy of point sources in the 102-320 nm range (Germany)
• LSS: Long-slit low-resolution (R~2500) spectroscopy in the 102-320 nm range
• ISSIS (Imaging and Slitless Spectroscopy Instrument for Surveys) being developed to carry out UV and optical diffraction limited imaging of astronomical objects. The ISSIS incorporates three channels:High Sensitivity Far-UV Channel: 120-200 nm; Channel for Surveys (FUV): 120-600 nm, optimized for 120-270 nm; Channel for Surveys (UVO): 120-600 nm, optimized for 270-600 nm. (Spain)

The international contributions were cancelled following the Russian attack on Ukraine and are to be replaced by Russian instruments.

The future of this project is uncertain. Originally a launch in May 2021 is planned. A switch to a Proton-M Blok-DM-03 launch vehicle is likely, as the Zenit-3F will be most probably phased out long before the planned launch date. It will be placed into a geosynchronous orbit with an inclination of 51.6�. Later the launch vehicle was changed to a Angara-A5 Orion. In May 2019, a launch date in October 2025 was announced, slipping to 2028. In December 2023, the launch date was postponed to 2030 due to lack of funding. Currently the launch date is expected no slip to 2035.