Proceedings of the 14th ISMSE & 12th ICPMSE, Biarritz, France, 1 to 5 October 2018. ANALYSIS OF FIRST DATA FROM ATOMIC OXYGEN MONITOR SYSTEM ONBOARD SLATS

JAXA has proposed a brand-new concept for satellites in low Earth orbit (LEO). The Super Low Altitude Test Satellite (SLATS) also known as “TSUBAME” is the first Earth observation satellite to adopt a “super low orbit” at an altitude lower than 300 km. Higher resolution optical observation and the reduced emission power of such active sensors as radar are expected in future Earth observations from super low altitude orbits. Launched on December 23, 2017 from the Tanegashima Space Center, SLATS successfully completed its critical operation phase. The Atomic oxygen MOnitor (AMO) is one of the mission sensors of SLATS. It consists of two mission sensors—the Atomic Oxygen Fluence Sensor (AOFS) and the Materials Degradation Monitor (MDM). The AOFS will obtain AO environment data in SLATS’s orbit. It consists of eight sensor heads (AOFS-Hs) and one set of readout electronics. For AO measurement, six Thermoelectric Quartz Crystal Microbalances (TQCMs) with polyimide sensors (AOFS-Hs) were mounted at several positions of the satellite. Two non-coated TQCM sensors were also mounted next to the AO sensors for measuring the contamination background. Two AOFS-Hs have shutter mechanisms that control incident AO fluence on the front of the AOFS-Hs. The MDM will observe the degradation of candidate materials selected for future use in super low altitude satellites. It consists of a sample control unit (MDM-S) and a CCD camera unit (MDM-C). Thirteen temperature-controlled samples were fixed at MDM-S. The samples are thermal control films, power cables, and an AO monitor material. MDM-C will take an image once a week with LED lights that illuminate from the front and back of the material surface. Such AMO data will be used for a design standard and material usage guidance on future satellites in super low altitude orbits. This paper presents the flight data of both the AOFS and MDM from January 1, 2018 to the middle of July 2018.