EPP

The China Seismo-Electromagnetic Satellite, launched into orbit from Jiuquan Satellite Launch Centre on February 2^nd, 2018 , is China’s first space satellite dedicated to geophysical exporation. The satellite carries eight scientific payloads including high-precision magnetometers to detect electromagnetic changes in space, in particular changes associated with global earthquake disasters. In order to encourage and facilitate use by geophysical scientists of data from the satellite’s payloads, this paper introduces the application systems developed for the China Seismo-Electromagnetic Satellite by the Institute of Crustal Dynamics, China Earthquake Administration; these include platform construction, data classification, data storage, data format, and data access and acquisition.

The CSES (China seismic electromagnetic satellite) was launched on February 2, 2018 in a circular polar orbit at an altitude of ~507 km. One of the main objectives of CSES is to search for and characterize ionospheric perturbations that can be associated with seismic activities, to better understand the generation mechanism of such perturbations. Its scientific payload can measure a broad frequency range of electromagnetic waves and some important plasma parameters. This paper is a first-hand study of unusual observations recorded by the CSES over seismic regions prior to four earthquakes with M >7.0 since the satellite's launch. CSES detectors measured irregularities near the epicenter of these four earthquakes. It is already clear that data from instruments onboard the CSES will be of significant help in studies of characteristics of ionospheric perturbations related to earthquakes and their generation mechanisms.

The High Precision Magnetometer (HPM) on board the China Seismo-Electromagnetic Satellite (CSES) allows highly accurate measurement of the geomagnetic field; it includes FGM (Fluxgate Magnetometer) and CDSM (Coupled Dark State Magnetometer) probes. This article introduces the main processing method, algorithm, and processing procedure of the HPM data. First, the FGM and CDSM probes are calibrated according to ground sensor data. Then the FGM linear parameters can be corrected in orbit, by applying the absolute vector magnetic field correction algorithm from CDSM data. At the same time, the magnetic interference of the satellite is eliminated according to ground-satellite magnetic test results. Finally, according to the characteristics of the magnetic field direction in the low latitude region, the transformation matrix between FGM probe and star sensor is calibrated in orbit to determine the correct direction of the magnetic field. Comparing the magnetic field data of CSES and SWARM satellites in five continuous geomagnetic quiet days, the difference in measurements of the vector magnetic field is about 10 nT, which is within the uncertainty interval of geomagnetic disturbance.