ASTERIA CubeSat becomes first to observe an exoplanet

Built by MIT and NASA’s Jet Propulsion Laboratory, ASTERIA started in 2010 as an undergraduate class project in Space Systems Engineering. Having launched onboard a resupply mission to the International Space Station (ISS) in August 2017, it was deployed from the ISS in November last year. After successfully completing its initial 90-day mission, the CubeSat then observed the transit of 55 Cancri e, a previously discovered exoplanet in the orbit of the Sun-like star, 55 Cancri A. As the exoplanet passed by the star, the CubeSat’s precision photometry detected a change in brightness of around 0.04 per cent.

The ASTERIA mission was designed to demonstrate key technologies, including very stable pointing and thermal control for making extremely precise measurements of stellar brightness in a tiny satellite. Earlier this year- as part of its primary mission - ASTERIA achieved pointing stability of 0.5 arcseconds and thermal stability of 0.01 degrees Celsius. These technologies are fundamental for precision photometry - the measurement of stellar brightness over time – and enabled the CubeSat to hunt for exoplanets.