Questions tagged [propagation]
This tag is used for questions related to the prediction of objects in orbit, or in the prediction of evolutions of orbits, using various orbital-mechanic models such as: "two-body", NORAD's SGP4/SDP4, ... and /or numerical integration algorithms.
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How would I use SGP4 to simulate the motion of an object in orbit?
Let's assume I wanted to assess the accuracy of SGP4 over time.
I have an archived set of orbital ephemerides taken from SpaceTrack for a non-active object over the last year.
If I picked an epoch say,...
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Integration of Varying Forces, Impulses in Simulators
I am a software dude working on a personal project for building a spacecraft simulation software. And I've been looking into numerical integration methods, and I am just confused on how to tackle the ...
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Orbit Determination from Position and Velocity
I'm working on a game, somewhat similar to KSP (no building rockets, just beautiful orbital acrobatics). It's in a "small" star system, radius of 6 AU, and it features celestial bodies ...
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ECI position and velocity from angular velocity
I need help with an orbital mechanics issue that I cannot figure out.
I have the initial ECI position and velocity ($r_{vec},v_{vec}$) of a certain satellite. Through them, the angular velocity, the ...
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Reducing degree of ICGEM's Gravity Field Models for orbit propagation
I would like to use one of the static gravity field models published at ICGEM for satellite orbit propagation. For example, EGM2008. Its degree is 2190. I would like to use only 360 (may be even less) ...
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GMAT Get States of Propagation
I am failing with the most simple thing ever:
I want to store the SC states of a Propagation over 1 day inside an array!
So the basic script would look like this:
...
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Difference between different numerical propagators
As a school project, I'm trying to model the evolution of a space-debris population orbiting around Earth. By doing researches, I found several numerical propagators.
Though, I couldn't find any ...
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Implemented analytical orbit propagator
Anybody knows about reliable open source implementation of analytical orbit propagator (for a generic orbit, given the initial state and not TLE)?
Possibly including up to J2 and drag also.
I have ...
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Draper Semianalytical Satellite Theory (DSST) C/C++ version
Anyone knows where one could find the Draper Semianalytical Satellite Theory (DSST) semi-analytical propagator code in C/C++?
I know Orekit includes the Java version inside its code.
An in general if ...
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What would the TLE data (Mean Motion, Eccentricity, Inclination, RAAN, Argument of Pericenter) of GEO and PO be like?
I am currently making a satellite tracker app for android. I want to test my orbit propagation algorithm and I want to make some made-up basic orbits, so I need to know how their TLE would be. I want ...
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Are J2 and J4 cases of EGM2008 and other spherical harmonics models?
EGM84, EGM96, EGM2008... are Earth gravity models that contain coefficients "up to" a number of degrees. When using GMAT, STK, MATLAB Aerospace, this parameter is the "spherical ...
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GMAT: What causes the error "ArrayTemplate error : dimension error"?
I have made various scripts that work with GMAT, but once in a while I get an "ArrayTemplate error : dimension error" error. I do not know what causes it, as in this case my script appears ...
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Ноw to configure mission sequence for propagate until desired date in GMAT?
In GMAT, I have a state of satellite for a date (for example, 24.04.2022). Now, I need to propagate its motion for some days forward, until selected date (say, 29.04.2022).
I added Propagation into ...
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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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Optimizing trajectories with GMAT: how to understand the "Vary" parameters, and how to know what values to use for them?
I've been using GMAT in my free time to optimize trajectories, and have varied burn component values and spacecraft states, usually with success. The vary command in GMAT, with the Yukon optimizer ...
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