Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Estimating Satellite Orbital Drag During Historical Magnetic Superstorms   Understanding extreme space weather events is of paramount importance in
efforts to protect technological systems in space and on the ground.
Particularly in the thermosphere, the subsequent extreme magnetic storms can
pose serious threats to low-Earth orbit (LEO) spacecraft by intensifying errors
in orbit predictions. Extreme magnetic storms (minimum Dst $\leq$ --250 nT) are
extremely rare: only 7 events occurred during the era of spacecraft with
high-level accelerometers such as CHAMP (CHAllenge Mini-satellite Payload) and
GRACE (Gravity Recovery And Climate experiment), and none with minimum Dst
$\leq$ --500 nT, here termed magnetic superstorms. Therefore, current knowledge
of thermospheric mass density response to superstorms is very limited. Thus, in
order to advance this knowledge, four known magnetic superstorms in history,
i.e., events occurring before CHAMP's and GRACE's commission times, with
complete datasets, are used to empirically estimate density enhancements and
subsequent orbital drag. The November 2003 magnetic storm (minimum Dst = --422
nT), the most extreme event observed by both satellites, is used as the
benchmark event. Results show that, as expected, orbital degradation is more
severe for the most intense storms. Additionally, results clearly point out
that the time duration of the storm is strongly associated with storm-time
orbital drag effects, being as important as or even more important than storm
intensity itself. The most extreme storm-time decays during CHAMP/GRACE-like
sample satellite orbits estimated for the March 1989 magnetic superstorm show
that long-lasting superstorms can have highly detrimental consequences for the
orbital dynamics of satellites in LEO.

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The categories of this paper are: econ
5
The categories of this paper are: gr-qc
33
The categories of this paper are: plasm-ph
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The categories of this paper are: stat
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The categories of this paper are: math
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The categories of this paper are: quant-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: supr-con
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The categories of this paper are: hep-th
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The categories of this paper are: atom-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: q-bio
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The categories of this paper are: eess
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The categories of this paper are: nlin
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The categories of this paper are: comp-gas
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The categories of this paper are: hep-ph