The Low-Latitude Ionosphere/Thermosphere Enhancements in Density (LLITED) Mission Science

Abstract:

The LLITED CubeSat mission, funded the through NASA HTIDs program, is a 1-year on-orbit mission to investigate to the Equatorial Ionization Anomaly (EIA) and the Equatorial Temperature and Wind Anomaly (ETWA) and their relationship. This will be the first time coincident high-resolution simultaneous thermosphere and ionosphere in situ observations of the features will be obtained. The EIA and ETWA are two of the dominant ionosphere/thermosphere interactions on the low-latitude duskside. While the EIA has been extensively studied both observationally and with modeling, the ETWA is less well known since observations are infrequent due to a lack of suitably instrumented spacecraft at appropriate altitudes. LLITED will characterize and improve our understanding of the ETWA, provide insight into the coupling physics between the ETWA and EIA, and increase our knowledge of the duskside dynamics that may influence space weather. We present the current state of knowledge of the field and describe specifically the contribution of LLITED. In addition to LLITED, there will be a number CubeSat and small sat ionosphere/thermosphere missions in-orbit simultaneously with LLITED. Some of these missions will obtain complementary measurements. We discuss the potential impact to LLITED science goals by utilizing these data sets.

The LLITED hardware is nearing completion (Dec. 2020-Jan. 2020). The mission consists of two 1.5U CubeSats in a high-inclination circular orbit, with an orbit altitude between 400 and 500 km. The CubeSats will maintain a 1/4 to 1/2 orbit separation to each other in order to observe any temporal changes as the ETWA/EIA evolve. The bus and subsystems are provided by The Aerospace Corporation. Both CubeSats will host three payloads: an ionization gauge (IG), planar ion probe (PIP), and GPS radio occultation sensor (GPSRO). The Aerospace Corporation is providing the IG and GPSRO sensors and Embry-Riddle is providing the PIP. The products provided are in-situ neutral pressure/density, in-situ plasma density, and slant TEC.