Citation: | Jiang,Y., Olsen, N., Ou, J. M., and Yan, Q. (2023). Simulation for MSS-2 low-perigee elliptical orbit satellites: an example of lithospheric magnetic field modelling. Earth Planet. Phys., 7(1), 151–160. doi: 10.26464/epp2023021 |
A future constellation of at least four geomagnetic satellites (designated Macau Scientific Satellite-1 (MSS-1) and Macau Scientific Satellite-2 (MSS-2)) was recently proposed, to continue high-quality geomagnetic observations in the post-Swarm period, focusing especially on collecting data that will provide a global, three-dimensional survey of the geomagnetic field. In this paper, we present a simulation of two years of orbits (2020.01.01−2022.01.01) of two satellites (tentatively denoted as MSS-2) that are constellated in elliptical (200 × 5,300 km) low-perigee orbits. By comparing error variances of Gauss coefficients, we investigate the sensitivity of lithospheric magnetic field modelling to data collected from various satellite orbits, including a near circular reference orbit of 300 × 350 km, and elliptical orbit of 180 × 5,300 km, 220 × 5,300 km, 200 × 3,000 km and 200 × 1,500 km. We find that in two years the two MSS-2 satellites can collect 35,000 observations at altitude below 250 km, data that will be useful in advancing the quality of lithospheric magnetic field modelling; this number of observations reflects the fact that only 4.5% of the flight time of these satellites will be below 250 km (just 6.4% of their flight time below 300 km). By combining observations from the MSS-2 satellites’ elliptical orbits of 200 × 5,300 km with observations from a circular reference orbit, the variance of the geomagnetic model can be reduced by a factor of 285 at spherical harmonic degree