Impact of variations in thermospheric mass density on the orbit propagation of low Earth orbit satellites

Paper number

IAC-18,A6,9,2,x45501

Author

Mr. Changyong HE, Australia, RMIT University (Royal Melbourne Institute of Technology)

Coauthor

Dr. Yang Yang, Australia, RMIT University (Royal Melbourne Institute of Technology)

Coauthor

Dr. Brett Carter, Australia, RMIT University

Coauthor

Dr. Haibing Ruan, China, University of Science and Technology of China

Coauthor

Dr. Florent Deleflie, France, Observatoire de Paris

Coauthor

Prof. Jiuhou Lei, China, University of Science and Technology of China

Coauthor

Prof. Kefei Zhang, Australia, RMIT University, Australia

Year

2018

Abstract

Thermospheric mass density (TMD) contains complicated and non-linear temporal and spatial variations caused by external forcing (e.g., solar and geomagnetic activities) and internal forcing (thermosphere-ionosphere coupling). With the help of an increasing number of TMD estimates from the low Earth orbit (LEO) satellites, more TMD variations have been recognised and quantified in space physics and upper atmosphere studies. Whilst the quantitative impact of these variations on the orbit propagation (OP) for LEO objects is still unknown. The present study will identify the impact of different TMD variations on the orbital dynamics for LEO targets and hence help to further improve the performance of OP-oriented empirical TMD models.

Comparative simulation of OP is carried out with or without different TMD variations in Table~\ref{tab} such as temporal (annual, semi-annual, solar cycles, solar rotation, storm time, etc.) and spatial variations (latitudinal and longitudinal variations). The equatorial mass density anomaly (EMA) is a two-cell structure, peaking at mid-latitudes and having a trough near the equator. The midnight density maximum (MDM) refers to the density maximum near the equator at midnight. These two variations are good examples which can be observed by LEO satellites and may have observable impact on LEO dynamics. Their mechanisms have been well-investigated and can be simulated by the physical atmospheric model, e.g., Thermosphere Ionosphere Electrodynamics General Circulation Model (TIEGCM). The other variations are simulated by the empirical model, i.e., NRLMSISE00. Note that all of the aforementioned variations are not strictly grouped by tempo-spatial variability since many of them (e.g., the EMA and MDM) are featured in both time and space. The difference between the predicted orbit of LEO satellites is presented and reveals the impact of these TMD variations on the orbital dynamics in LEO. Some recommendations for the TMD modelling are also formulated.

\begin{table}[htb]
\centering
\begin{tabular}{lccc}
  \hline
   & Magnitude(\%) & Time/Period & Latitude\newline ($^\circ$)  \\ 
  \hline
  Annual 	    & 5--35 & all	& all \\
  Semi-annual   & 5--25 & all 	& all\\
  Solar cycle   & 20--100    & 11 yrs	& all\\
  Solar rotation& 0--5 	& 27 days	& all\\
  Storms 		& up to 100 & hourly	& all\\
  Latitudinal 	& 20--40 	& all 	& all\\
  Longitudinal  & 0--10 	& all 	& all\\
  MDM 			&20--30 & local summer (23--01 LT) & $[-10,10]$\\
  EMA & 1--6 & 10--20 LT & $[-40,40]$\\
  \hline
\end{tabular}
\caption{Variations in TMD at 200--800~km (MDM: midnight density maximum; EMA: equatorial mass density anomaly).}
\label{tab}
\end{table}

Abstract document

IAC-18,A6,9,2,x45501.brief.pdf

Manuscript document

IAC-18,A6,9,2,x45501.pdf (🔒 authorized access only).

To get the manuscript, please contact IAF Secretariat.