ASTERIA (Arcsecond Space Telescope Enabling Research in Astrophysics) is a technology demonstration of astrophysical measurements using a Cubesat, with a primary goal of training early-career engineers. ASTERIA has been developed under JPL's Phaeton Program to provide recent college graduates, under the guidance of experienced mentors, with real, rapid, hands-on exposure to the multiple disciplines and phases of a flight project. ASTERIA's technical goal is to achieve arcsecond-level line-of-sight pointing error and highly stable focal plane temperature control. These technologies are important for precision photometry, i.e., the measurement of stellar brightness over time. Precision photometry, in turn, provides a way to study stellar activity, transiting exoplanets, and other astrophysical phenomena.
ASTERIA is a 6U CubeSat (roughly 10 x 20 x 30 cm, 12 kg) that will operate in low-Earth orbit. The payload consists of a lens and baffle assembly, a CMOS imager, and a two-axis piezoelectric positioning stage on which the focal plane is mounted. A set of commercial reaction wheels provides coarse attitude control. Fine pointing control is achieved by tracking a set of guide stars on the CMOS sensor and moving the piezoelectric stage to compensate for residual pointing errors. Precision thermal control is achieved by isolating the payload from the spacecraft bus, passively cooling the detector, and using trim heaters to perform small temperature corrections over the course of an observation.
In June 2017, the flight spacecraft was delivered for integration into the Nanoracks Cubesat Deployer. ASTERIA was launched to the International Space Station (ISS) with the SpaceX Falcon-9 Crew Resupply Services – 12 (CRS-12) mission on August 14, 2017. The spacecraft was deployed from the ISS on November 20, 2017 to begin the 90-day ASTERIA technology demonstration mission.
The ASTERIA project is a collaboration with MIT and is funded at JPL through the Phaeton Program for training early career employees. JPL is responsible for overall project management, systems engineering, spacecraft implementation, integration and test, and mission operations. The main spacecraft subsystem suppliers are Blue Canyon Technologies (Attitude Control Subsystem), Vulcan Wireless (Telecommunications Subsystem), MMA Design LLC (Solar Arrays), GomSpace (Power subsystem and Batteries), Spaceflight Industries (Flight computer), Ecliptic Enterprises (Focal Plane), Physik Instrumente (piezo stage), and Thermotive (thermal hardware). Morehead State University will provide spacecraft tracking, telemetry, and control services to the Mission Operations team at JPL. MIT will perform target selection and analysis of stellar photometry data from ASTERIA.