NASA Interferometer to Study the Sun Using Small Sats

The Sun Radio Interferometer Space Experiment (SunRISE) mission uses smallsat technologies to create a space-borne interferometer. The mission will differentiate hypotheses on how magnetic energy in the corona is converted into intense relativistic particle radiation and how this radiation propagates into interplanetary space. SunRISE will localize solar radio emissions using a >10-km wide synthetic aperture consisting of six identical space vehicles. The Observatory will fly ~300 km above geosynchronous Earth orbit (GEO) in a passive formation. Each space vehicle (SV) is a 6U form-factor spacecraft with a payload comprised of decametric-hectometric (DH, 0.1 MHz–23 MHz) and global navigation satellite system (GNSS) receivers. The DH receiver observes Type II and Type III solar radio bursts. The GNSS receiver provides position and timing information for the DH measurements. SunRISE is unique in that the “instrument” is a combination of the six payloads in space and the ground processing system. The observing scheme features some key simplifications that enable the SunRISE architecture. SunRISE leverages several state-of-the-art capabilities to accomplish its mission. The SVs are built and in storage awaiting launch. This paper will describe the SunRISE mission, the architecture and technologies employed, and some of the challenges faced in its development.