ASTERIA ( Arcsecond Space Telescope Enabling Research In Astrophysics ) is a 6U CubeSat space telescope ( 10 cm x 20 cm x 30 cm , 10 kg ) .
ASTERIA ’ s primary mission objective was demonstrating two key technologies for reducing systematic noise in photometric observations : high-precision pointing control and high-stabilty thermal control .
ASTERIA demonstrated 0.5 arcsecond RMS pointing stability and \pm 10 milliKelvin thermal control of its camera payload during its primary mission , a significant improvement in pointing and thermal performance compared to other spacecraft in ASTERIA ’ s size and mass class .
ASTERIA launched in August 2017 and deployed from the International Space Station ( ISS ) November 2017 .
During the prime mission ( November 2017 – February 2018 ) and the first extended mission that followed ( March 2018 - May 2018 ) , ASTERIA conducted opportunistic science observations which included collection of photometric data on 55 Cancri , a nearby exoplanetary system with a super-Earth transiting planet .
The 55 Cancri data were reduced using a custom pipeline to correct CMOS detector column-dependent gain variations .
A Markov Chain Monte Carlo ( MCMC ) approach was used to simultaneously detrend the photometry using a simple baseline model and fit a transit model .
ASTERIA made a marginal detection of the known transiting exoplanet 55 Cancri e ( \sim 2 R _ { \oplus } ) , measuring a transit depth of 374 \pm 170 ppm .
This is the first detection of an exoplanet transit by a CubeSat .
The successful detection of super-Earth 55 Cancri e demonstrates that small , inexpensive spacecraft can deliver high-precision photometric measurements .