1. VLST workshop; STScI February 2004 1 UV astronomy in the post- GALEX era Noah Brosch Wise Observatory Tel Aviv University Israel

2. VLST workshop; STScI February 20042 Missions described TAUVEX on GSAT-4 TAUVEX on GSAT-4 Israeli mission on Indian geo-sat (2005/6) Israeli mission on Indian geo-sat (2005/6) UVIT on ASTROSAT UVIT on ASTROSAT UV/optical imagers on multi-spectral astronomy mission of India (2007/8) UV/optical imagers on multi-spectral astronomy mission of India (2007/8) WSO/UV WSO/UV International large space telescope for UV astronomy (2008+) International large space telescope for UV astronomy (2008+)

3. VLST workshop; STScI February 20043 GSAT-4 and TAUVEX TAUVEX: from SRG to GSAT-4 TAUVEX: from SRG to GSAT-4 Mode changed from pointed observations to sky scans Mode changed from pointed observations to sky scans Three-telescope array: 20-cm & 1 degree FOV, four filters/telescope Three-telescope array: 20-cm & 1 degree FOV, four filters/telescope

4. VLST workshop; STScI February 20044 The GSAT-4 satellite The GSAT-4 Spacecraft is an Experimental Technology Demonstrator for Advanced Satellite Communication Systems. TAUVEX is its only scientific payload

5. VLST workshop; STScI February 20045 TAUVEX on GSAT-4 GSAT-4 consists of: Ka-Band Regenerative and Bent Pipe transponder Ka-Band Regenerative and Bent Pipe transponder Geostationary Navigation Payload Geostationary Navigation Payload Scientific Payload (TAUVEX) Scientific Payload (TAUVEX) Bus System experiments Bus System experiments

6. VLST workshop; STScI February 20046 TAUVEX on GSAT-4 TAUVEX on rotating platform TAUVEX on rotating platform Constant-declination scans Constant-declination scans Dedicated high- speed telemetry link (always available) Dedicated high- speed telemetry link (always available)

7. VLST workshop; STScI February 20047 Expected performance Assume low straylight (best case) Performance with SF-2 (210+/-20 nm) for different spectral types Lines for monochromatic mag. 17, 18, 19, 20, 21 star

8. VLST workshop; STScI February 20048 ASTROSAT is an Indian-national scientific satellite to be launched in 2007. Polar orbit (sun-synchronous) offers long integrations only in CVZ. Operation to be targeted to interesting sources.

9. VLST workshop; STScI February 20049 UVIT to operate in conjunction with the X-ray telescopes

10. VLST workshop; STScI February 200410 World Space Observatory/UV WSO/UV: 1.7-meter telescope at 2 nd Lagrangian point. Its mission: high spectral resolution UV spectroscopy, combined with high-angular-resolution imaging. Image quality: 80% enclosed energy= 0”.35@633 nm & 0”.07@122 nm Main instruments: 2xHIRES (R=55000) +one long slit R~1000 spectrograph. http://wso.vilspa.esa.es

11. VLST workshop; STScI February 200411 WSO/UV: imaging focal plane Six imaging devices: four for UV and two for optical. Wide field=5 arcmin @ 0”.15/pixel (f/10); high resolution=1 arcmin FOV @ 0”.03/pixel (f/50). Integral filter wheels (six filters+empty position per camera)

12. VLST workshop; STScI February 200412 When will WSO/UV happen? T170M telescope @ Lavotchkin