The main instrument of the observatory is a 170-cm telescope based on the classic Ritchey-Chretien scheme. The telescope (T-170M) is composed by the optical system, a structural module and a service complex. The primary mirror unit (PMU) is the main structural element of the telescope.
There are three attachment points between the telescope and the spacecraft service module in the bottom frame part. The optical bench with the scientific instrumentation devices, and the primary mirror baffle are mounted on the PMU frame. The secondary mirror unit (SMU), the light protective cover with the deployment mechanism, and the rotary external baffle with its fixing unit are located in the top part of telescope tube. The external rotary baffle has an oblique cut for light exposures prevention of the telescope internal cavity. It can be put in two positions: transport and operational. The translation of the external baffle from the transport position to the operational one is carried out after spacecraft insertion onto the low Earth orbit (LEO) by turning it by 180 deg. The turning is performed by the actuators located on the top frame parts of the telescope. The T-170M telescope is based on the classic Ritchey-Chretien scheme.
The telescope is under development by Lavochkin Association (Russia). Optical elements are being manufactured by the Lytkarino Optical Glass Factory (Russia). Space qualification is under responsibility of the Institute of Astronomy RAS (Russia). The primary mirror and other optical elements is being manufactured by the Lytkarino Optical Glass Factory (Russia).The T-170M telescope has assimilated the successful experience gained during the fulfillment of the "Astron" project. In 2012 the telescope passed through the heat-vacuum tests.
|Primary mirror diameter||170 cm|
|Focal length||1700 cm|
|Field of view||30 arcmin|
|Angular resolution on focal plane||12.13 arcsec/mm|
|Image quality||close to the diffraction limit in the center of the field of view|
|Pointing accuracy||0,1 arcsec|
|Size||5.67 x 2.30 m (8.43 x 2.3 m)|