Professor Horst Cerjak, 19.12.20051
BRITE 2014
W.Weiss, R.KuschnigUniversity of Vienna
BRITE Constellation – 2 Years in Orbit
O. Koudelka, M.Unterberger, P.Romano Graz University of Technology
Professor Horst Cerjak, 19.12.20052
BRITE 2014
Contents
• Scientific Goals• Mission Description• Operations• Scientific Data Collection and Analysis• Summary
Professor Horst Cerjak, 19.12.20053
BRITE 2014
• First nanosatellite constellation dedicated to an astronomy mission (astereoseismology)
• 5 spacecraft operational in Space• Austria (BRITE-Austria/TUGSAT-1 & UniBRITE)• Poland (BRITE-PL1 „Lem“ & BRITE-PL2 „Heveliusz“)• Canada (BRITE-CAN1 „Toronto“)
BRITE (BRIght Target Explorer)
Professor Horst Cerjak, 19.12.20054
BRITE 2014
Scientific Goals• Photometric measurement of brightness and
temperature variations of massive luminous stars (up to visual magnitude 4)
• Fastest data cadence: few minutes
• Time base: up to 2 years
• high duty cycle
• 2-colour (blue and red)
• 24° field of view
Professor Horst Cerjak, 19.12.20055
BRITE 2014
BRITE Flight Model
telescope
star tracker
solar cells
magnetometer
S-band antenna
Size: 20 x 20 x 20 cm
Mass: 6.8 kg
Power: 6…10 W
S-Band downlink (256 kbit/s)
UHF uplink (9.6 kbit/s)
Professor Horst Cerjak, 19.12.20056
BRITE 2014
Launch
• TUGSAT-1/BRITE-Austria andUniBRITE were launched byPSLV-C20 of ISRO/ANTRIX on 25 February 2013from the Satish DhawanSpace Centre in Sriharikota
• Sun-synchonous LEO orbit
Courtesy: ISRO
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Mission Operations
• 14 orbits per day • 3 orbits in morning sequence• 3 - 4 orbits in evening sequence
• Automatic & remote ground stations operations supported
• BRITE-Austria operated from Graz• UniBRITE operated from Toronto
Professor Horst Cerjak, 19.12.20058
BRITE 2014
Management
• BRITE Executive Science Team (BEST)�Scientists from Austria, Canada, Poland�Defines targets
• Operation teams�Prepare commands for spacecraft, �up- and downloads
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BRITE 2014
Satellite Performance
• RMS pointing stability in X / Y: 1.6 / 1.5 pixels (2 – 3 pixels)
• Up to 20 subrasters: 32x32 to 24x24 pixels
• Typical 1 sec integrations, stacking available
• CCD deterioration due to radiation -> chopping
Attitude Spacecraft temperature
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Raster Photometry
• Raster: 24 x 24 pixels
All 15 rasters during one observation, spacecraft pointing at Orion
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BRITE 2014
Ultrapraecision
from ground in space
11
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BRITE 2014
Observations Planning
Professor Horst Cerjak, 19.12.200513
BRITE 2014
Life Cycle of MatterLife Cycle of Matter
White DwarfsNeutron StarsBlack Holes
Professor Horst Cerjak, 19.12.200514
BRITE 2014
Light Curve for Orion
Gray curve: TUGSAT-1/BRITE-Austria (blue filter)Bllue curve: UniBRITE (red filter)
Professor Horst Cerjak, 19.12.200515
BRITE 2014
Bright Star Bonus� Interferometry
• angular diameter
� Adaptive Optics & Lucky Image
• stellar & debris disks
� Parallax with high accuracy
• linear diameter
� Very high spectral resolution spectroscopy
• stellar fundamental parameters & atmosphere
• (Doppler) surface imaging
� Time resolved spectroscopy
• asteroseismology
� Spectropolarimetry
• magnetic field structures
� Multi-wavelengths options
� ““““Easy”””” access to telescope time
of medium size telescopes
Professor Horst Cerjak, 19.12.200516
BRITE 2014
Summary
• BRITE-Constellation is the world‘s first nanosatellite constellation dedicated to astronomy
• 5 components of BRITE-Constellation operational
• Scientific & technical requirements fully met
• Science fields: 150d in Orion, Centaurus, Perseus, and Vela Pupis.
• Observing program developed till end 2016
• Scientific data analysis under way
Professor Horst Cerjak, 19.12.200517
BRITE 2014
Professor Horst Cerjak, 19.12.200518
BRITE 2014
Thank you for your attention!