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BRITE - Constellation. BRI ght T arget E xplorer. BRITE-AUT. BRITE-CAN. BRITE-POL. high precision photometry (~mmag) selected very bright stars (<4 mag) 15 stars per field minimum (24deg FOV) obtained during at least 15min per orbit (100min)
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BRITE - Constellation BRIghtTargetExplorer BRITE-AUT BRITE-CAN BRITE-POL
high precision photometry (~mmag) selected very bright stars (<4 mag) 15 stars per field minimum (24deg FOV) obtained during at least 15min per orbit (100min) in (at least) two wavelength regions (blue-red) long time base observations (180 d/y/field) all sky access including polar regions 3 years lifetime per satellite (minimum 2) 1MByte/day science data (compressed) BRITE Mission Goals
BRITE Photometry 101min BLUE- RED
BRITE Sky BRITE: BRIghtTargetExplorer
BRITE Target Stars Selection • 42 proposals have been submitted • 13 PI‘s and their teams • Austria (15), Australia (1), • Belgium (2), Bulgaria (1), • Canada (4), Croatia (1), • Germany (6), Iran (1), Poland (2), • Spain (1), Switzerland (1), U.K. (3) and USA (3) • O, B and Be stars, beta Cephei stars, hot Supergiants, • delta Scuti variables, gamma Doradus pulsators, • roAp / CP stars, red Giants , eclipsing binaries and more BRITE CANDIDATE TARGET STAR CATALOG BRITE-sky: a target fields evaluations tool
BRITE - Constellation • nano-satellites • 20cm cube spacecrafts <8kg • 3 axis pointing control • LEO sunsynchronous (polar) orbit • small aperture (3cm) telescopes • wide (24deg) field of view • one instrument is RED sensitive one BLUE
BRITE Orbit and Observing Strategy • Low Earth Orbit (LEO) Sun-Synch • (Dawn-Dusk) • 820 km, LTDN 6AM (BRITE_AUT) • Orbit Period ~ 101min • 15-40min/per orbit per field • 1-3 fields per orbit • 180-220 days per year • 300 days per year (near pole) Sun
BRITE-AUT Launch Madras SFL is contracted to launch BRITE-AUT Q1-2011
BRITE Instrument - Telescope 5 lens system plus filter & baffle RED design BLUE design for a 24 deg cicular FOV, telecentric low distortion, mimimal vignetting
BRITE Detectors KODAKKA11002 good performance at high (+20C) temperatures low power consumption and reasonable price ReadNoise ~15e rms
BRITE – Point Spread Function ZEMAX Model PSF - 5 deg offsets BRITE Blue 0.50 0.73 1.07 1.29 0.83 0.61 0.52 +0.3 +0.2 +0.1 0.0 -0.2 -0.3 -0.1 red: rms scatter in mmag black: CCD distance in [mm] design best focus extra focal intra focal
BRITE – Point Spread Function ZEMAX Model PSF - 7 deg offsets BRITE Red 0.46 1.31 1.19 1.01 0.85 0.56 0.40 +0.3 +0.2 +0.1 0.0 -0.1 -0.15 -0.20 red: rms scatter in mmag black: CCD distance in [mm] design
BRITE Point Spread Function BRITE Blue PSF 5 deg offsets 8 pixels diameter – 80 pixels carry signal~30“/pixel
BRITE – Field Of View 30“/pixel 2670 pixel 4000 pixel
Region of Interest ROI/Raster up to 15 (32x32pixel) ROI/Raster
ROI Rnnn X2 Y2 RnnnB2 RnnnB3 RnnnA2 RnnA1 V pix BW pix RnnnB4 RnnnB1 BW pix H pix Y1 X1 BRITE Onboard Data Processing sections: RnnnB1-4 ... backgrounds RnnnA1-2 ... apertures processed data: for each background median and sigma are calculated + the sum of signals values encompassed in the two apertures a total of 10 values BW ... width of background [pixels]
BRITE Photometric Performance mag(V) mag(V) = 0-> 1.3 sec / 14 exp per min scatter mag(V) = 2-> 8.0 sec / 5 exp per min mag(V) = 4-> 50.0 sec / 1 exp per min
BRITE Operational Software Science Data Generation Code
BRITE Ground Station(s) • Primary Ground Station: IKS – TU Graz • Additional Locations: UTIAS – Toronto Canada TU Wien IfA Uni Wien
BRITE-AUT Project Timeline • development of the hardware and software • completion of two satellites June 2010 • launch targeted for January 2011 http://www.brite-constellation.at