Questions tagged [two-line-elements]
Set of values carefully prepared to be used together with a simplified perturbations model (most often SGP4) to predict satellite positions with a moderate level of accuracy for times near the epoch contained within the TLE.
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What happens when the 3-letter suffix space of a SATCAT ID gets exhausted?
The ISS' SATCAT ID is 1998-067A.
The CubeSats and other objects released from the space station are considered its sub-units, thus using different suffixes: 1998-067C, etc.
The same principle applies ...
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TLE/SGP4 state vector accuracy assessment
I’m using the Planet Labs state vectors downloadable from http://ephemerides.planet-labs.com/planet.states or http://ephemerides.planet-labs.com/planet_YYYYMMDD.states to assess the TLEs/SGP4 accuracy ...
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Equinoctial Elements and Perturbative Effects
I have an Orbital model in Equinoctial Elements (paper). There is a perturbative acceleration term in the model.
Can someone point me to some relevant papers showing how to include different ...
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How to generate TLEs based on a set of observation points (location, azimuth, elevation... no range)
I'm interested in generating a "corrected TLE1" based on observation data. I would have observed azimuth and elevation, site location, and time. All of those data fields are observed with ...
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Second derivative of mean motion as indicator of deorbit
I noticed that the second derivative of mean motion (SDMM) is non-zero for only a small percentage of the NORAD catalog. All those objects I checked have reentered since the TLEs I was using were ...
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Where is this LightSail-2 trajectory data coming from? Is there more than TLEs available to the public?
This tweet shows high granularity data for LightSail-2's perigee and apogee, showing that while the apogee-raising strategy is working nicely, currently atmospheric drag is taking its toll and the ...
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Pre-launch TLEs for NASA launches
I was curious if the United States is on the verge of launching maned flights to the ISS, will anyone release Pre-Launch TLE data like was done back when the shuttle was flying.
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Regarding the vernal equinox and calculate a TLE code
I am utterly confused as to how the ecliptic co ordinate system works.
My understanding is that the vernal equinox is comparable to greenwich for longitude here on earth. But how do we know where the ...
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How do I know the exact TLE of my satellite after its deployment?
The satellites are launched in a cluster. How can I validate the TLE of my satellite in the early days following deployment, because there are more than two satellites that are close to each other and ...
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Calculating Which Satellite Passes are Visible - Need help
I am a beginner Python programmer. I am trying to get the code in the article "Calculating which satellites are visible" to function without success. My plan is to identify satellites that ...
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Where can i find ELSETS with Co-Variances?
For Special Permutations (I'm a novice), an ELSET with covariance is more accurate than without covariance. A TLE doesn't have room for any covariance. However, I can't seem to find a catalog that ...
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Where can I find a satellite/space debris database with object masses
The title pretty much says it all. As far as I can tell the default method by which space debris objects are tracked/stored in a database is using two line element sets. However these have no way to ...
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How can I "debounce" these TDRS satellite inclinations? (reconstruct the zero-crossings)
The plot below is from the question Why do the geosynchronous TDRS satellites have this distribution of inclinations?, and the explanation says
Inclination and mean motion (rev/day) for TDRS ...
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CSpOC’s identical TLEs
Identical TLEs are often published by CSpOC at https://www.space-track.org/.
For example, here’s the first line of the three newest TLEs for IRNSS-1H:
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How can I plot a precessing orbital plane of an artificial satellite on a polar plot from a TLE in Python?
How can I plot the orbital plane of an artificial satellite on a polar plot from a TLE in Python?
Very new to all of this. As I understand it I need to extract TLE's from Space-track.org. Then use ...
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Is there a python library to determine the position of a satellite at a given time from TLE data excluding the Satellite catalog number?
Or perhaps some simple code or formula that achieves this. I've used pyephem but it requires a Satellite catalog number.
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Issue with propagating TLE sets using SGP4
I am trying to make some analysis on conjunction events using the TLEs available from Celestrak's SOCRATES page. Take for example the following predicted event:
Here's my issue: when I try to ...
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calculating satellite position and velocity from TLE
I'm trying to calculate satellite orbit from the TLE set
at first, I used several libraries including SGP4, Skyfiled to get the initial position and velocity of the satellite at the epoch time
I know ...
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Given the measured positions of an object, how to retrieve its latest TLE?
I'm working on a simulation space project, in which I simulate the positions of all the Low Earth Orbit objects at any time.
For the moment I have a 3LE database of LEO objects, and each time a ground ...
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Did Tianzhou-2 have a TLE before docking with Tianhe 8 hours after launch? Which is the 2nd stage rocket body and roughly how soon will it reenter?
Clicking on https://celestrak.org/NORAD/elements/stations.txt I get
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Calculate ground track from CCSDS OEM
Are there open source solutions (preferable Python) to calculate the ground track of a spacecraft (i.e. in latitute/longitude) from CCSDS OEM (orbit ephemeris message) format (which is a dataset of ...
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Elevation and Azimuth of satellite in different location
I know the Elevation and Azimuth of the a specific GPS satellite (I have the RINEX files of the station in a specific Location 4.4801,-73.3433; in order to calculate this), but I want to know the ...
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Use ECI cordinates to plot orbit in three.js
I am using satellite.js to get ECI coordinates from TLE data. Now my first question is can ECI coordinates be used to plot satellite orbit as shown here.
If yes then how can i do that in three.js?
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What are common problems when downloading and processing TLE data from Space-Track?
A few of my colleagues and I are trying to download the latest version of the TLE Catalogue from space-track. We've been using the Space-Track TLE Retriever 3 program and we've been able to download ...
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Is Vallado's Revisiting Spacetrack Report #3 still relevant today?
The title pretty much sums it up. I am reading David A. Vallado's Revisiting Spacetrack Report #3, which was published in 2006 and includes source code for the SGP model series. I was wondering, is ...
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