Linked Questions
24 questions linked to/from How do SDP4's "Deep space" corrections to SGP4 account for the Sun's and Moon's gravity?
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Can the deactivated satellites also be tracked through TLE?
TLE is used to track whether the satellites are in orbit or not. However, is it possible that a particular satellite is deactivated, decommissioned or deorbited yet its TLE is being updated regularly?
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Is SGP4 propagation necessarily more accurate near the epoch chosen for TLE generation?
This interesting answer includes a quote from Space-Track:
From Space-Track.Org FAQ
TLEs can contain future epochs.
About 20 satellites are categorized as "multi-day objects" because ...
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TLE SGP4 Coordinate Transformations
I am working on developing a user friendly SGP4 orbit propagator in C on a PIC24.
I have extensively read Revisiting Spacetrack Report #3 and celestrak - there are a few outstanding questions I have.
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Why are Tiangong-1's Apogee and Perigee Graphs Wobbly?
The apogee and perigee graph of the Tiangong-1 space station, about to re-enter and break up Real Soon Now, is depicted in this graph (source: Wikipedia):
Why are the graphs wobbly? Is it because the ...
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Sun-synchronous satellite orbit propagation
I'm trying to propagate the orbit of a sun-synchronous satellite. The initial data is defined by the TLE.
The orbit of the satellite is controlled by the operator ...
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How can I plot a satellite's orbit in 3D from a TLE using Python and Skyfield?
I have obtained a Two Line Element (TLE) of a satellite in Earth orbit from Celestrak at https://celestrak.org/NORAD/elements/ and I would like to use it to calculate an orbit.
How can I calculate the ...
- 148k
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Has a TLE ever been issued for a spacecraft trajectory not bound to Earth orbit?
This excellent answer to the question Why has no TLE been published for the DSCOVR satellite and the Falcon 9 R/B? suggests that to the best of the writer's knowledge TLEs are only issued for ...
- 148k
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Why are Keplerian elements used in TLEs instead of Cartesian state vectors?
Propagating a state vector seems easier, you just account for the gravity, change the velocity and update the position.
It also allows to easily apply perturbations, etc.
Additionally, the ...
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How to obtain UTC of the epoch time in a satellite TLE (two line element)?
I want to convert the epoch time of a TLE to UTC. At this moment I am less interested in explanations and history - I just want to know quantitatively, with certainty, how to convert.
I'm confused ...
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