ISEND cubesat for studying the Earth's exospheric density and its response to space weather
Abstract
The Instrument for Studying Exospheric Neutral Density (ISEND) is a 7-month, 12U cubesat mission with a primary goal of understanding the evolution of the Earth's outermost atmosphere under various solar irradiance and space weather conditions. The Earth's exosphere is the outermost atmosphere and composed of mostly hydrogen atoms. The exospheric neutrals are used to remotely sense the Earth's magnetospheric system. For examples, TWINS ENA instruments have and SMILE soft X-ray imager will visualize charge exchange processes between exospheric neutrals and charged particles. However, our exosphere is not steady. It gains and loses hydrogen atoms as a result of the sun - solar wind - magnetosphere - plasmasphere - upper atmosphere interactions. Study of the neutral density distribution and its response to space weather is key to understand the whole evolutionary history of the Earth's atmosphere, advance our knowledge of the Sun - Earth interactions, and improve our analysis of the remote-sensing dataset. In spite of the importance of exospheric hydrogen density (NH), the in-situ NH measurements above 1 RE altitude are very rare. Instead, the observations of geocoronal column brightness have been widely used to develop the exospheric neutral density models. However, due to the complex inversion techniques and background removals, discrepancy between the models are up to 200%. ISEND will provide unprecedented, in-situ measurements of exospheric hydrogen density along a highly-elliptical geosynchronous transfer orbit with two instruments on board: a high-heritage, flight-proven Neutral Mass Spectrometer (NMS) for accurate NH measurements and a compact, commercially-built micro-DOSimeter (DOS) for synchronously characterizing the NMS penetrating radiation noise environment. Study of the ISEND data will address the Earth's atmospheric evolution, its potential impact on the nearby space environments, and furthermore the evolution of other planetary atmospheres since the atmospheric escape of light gases is ubiquitous across our solar system and beyond.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2020
- Bibcode:
- 2020AGUFMSA023..01C
- Keywords:
-
- 0394 Instruments and techniques;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 2494 Instruments and techniques;
- IONOSPHERE;
- 2794 Instruments and techniques;
- MAGNETOSPHERIC PHYSICS;
- 7894 Instruments and techniques;
- SPACE PLASMA PHYSICS