T-170-M telescope, cameras and the FGS: interfaces, requirements etc.

1. ASI/Roscosmos Meeting Rome, December 20, 2005 T-170-M telescope, cameras and the FGS: interfaces, requirements etc. Alexander MOISHEEV Lavochkin Association moisheev@laspace.ru

2. TheWSO/UV S/C

3. S/C main features • Platform (Service Module –SM) Navigator • Mass of S/C with propellant 2900 kg • SM mass 1300 kg • Mass of propellant of the SM 150 kg Propellant of the SM: Hydrazine • Mass of the P/L 1600 kg • Pointing accuracy with star sensors4 (2) arc.min. • Accuracy of pointing and stabilization 0.1 arc.sec with the FGS;

4. S/C main features (ctd.) • Slewing rate up to 0.1 deg/s • Maximal exposure time 30 hours • Download rate of scientific data up to 1 Mbaud • H/K data transmission rate up to 32 Kbps • Electric power available for the P/L 750 W For science instruments of the 300 W Focal Plane Compartment • Voltage of electric power supply 27±1,35V

6. Initial design requirements to T-170M

7. T-170M FP layout HIRDES slits are placed 50mm off-axis SFUV cameras: FOV- 6 arcmin circular SFVIS camera: FOV- 6x6 arcmin squared FOV’s centers are located 30mm off-axis LFUV cameras: FOV- 1.2 arcmin circular LFVIS camera: FOV- 1.2x1.2 arcmin squared FOV’s centers are located 35mm off-axis FGS cameras FOV- 4x3 arcmin rectangular FOV’s centers are located 60mm off-axis Optics Quality Control System is on axis FOV - non Spectropolarimeter (excluded) FOV – 6 arcmin circular FOV’s center is located 60 mm off-axis Optical Adjustment Control System is placed 60mm off-axis (proposed)

8. Exploded view of the instrumental compartment

9. Field cameras Concept: All cameras in one unit – Field Cameras Unit For estimates of size, mass, electrical properties etc the TAUVEX camera (Israel) is considered as prototype of the UV-cameras

10. Field Cameras Unit (FCU) SF-UV1 LF-UV2

11. FCU structural design • 6 cameras - 3 cameras for operation in the standard mode F/10 ( 2 - SFUV cameras, 1 - SFVIS camera); - 3 cameras for operation in the long focus mode (f/50) (2 - LFUV cameras, 1 - SFVIS camera). • Light-splitting unit; • FCU electronic subsystem (Module of Control and Processing of Data, Power Supply Sources); • FCU structure, unifying all FC in the monoblock unit.

13. FCU features • Spectral ranges: - UV 110 - 350 nm - visible 350 – 700 nm • Image quality - SFUV cameras, SFVIS camera 0.3 arc.sec; - LFUV camera, LFVIS camera 0.1 arc.sec. • Mass of each FC not higher than 1 kg • Power consumption 15 W of each FC not higher than • Maximal power consumption 50 W of the FCU not higher than

14. FCU accommodation

15. Thermal environment of the field cameras • Operation temperature range, C +10 -- +30 • Temperature range during assembling +18 -- +25 and tests • Temperature range during storage +5 -- +35 and transportation of the telescope • Critical temperature range -40 -- Toutgas Toutgas should be defined

16. The Fine Guidance System - FGS The concept: The FGS uses images of guiding stars from the T170M telescope FGS detectors are firmly attached to optical bench in the nearest vicinity of the spectrographs entrance slits The FGS consists of: • three identical detectors (CCD(?) + electronics) • common Data Processing Unit (DPU) • software including Master Catalogue

18. FGS requirements • General:FOV and throughput should provide with the capacity to detect at the level of S/N > 3 at least two guiding stars for the exposure time defined by angular velocity drift of the S/C • Mass of sensor 0.25 kg • Power consumption of sensor 0.6 W not higher than • Mass of the Data Processing Unit 7 kg • Power consumption of the DPU 35 W not higher than

19. Thank you for your attention!