Questions tagged [coordinates]
Questions about sets of data used to determine a unique point in a given space, e.g. (degrees North, degrees East) for geographic coordinates
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Definition of ECL50 coordinate frame?
Is there a document with the definition of the "ECL50" frame? It was used at least in the Voyager and Ulysses missions. I have seen in literature people saying "ECL50 is the same as ...
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Are ECI and ECEF Frames, and Do They Belong to the Geocentric Equatorial Coordinate Systems?
I'm completely confused about the difference between geocentric equatorial coordinate systems, ECI, and ECEF. David Vallado, in his book 'Fundamentals of Astrodynamics and Applications,' mentions that ...
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How does the Gpredict software algorithm track satellites?
I was wondering how Gpredict calculates the ground tracks, Lat, Long and elevation based on a ground station.
If I understand correctly, Gpredict takes the values from a TLE (Two-Line Element) set, ...
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How to convert Geocentric Coordinates to ECEF using Skyfield?
I'm trying to obtain ECEF coordinates from geocentric coordinates and then plot the ground track using the subpoint function. Any advice? My objective is to create an accurate ground track.
Additional ...
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When solving flight dynamics equations, should the integration variables be set in one or multiple reference frames?
when establishing the differential equations of flight dynamics, I have 2 choices:
1、establish the equations in one coordinate system (e.g. in the earth centered inertial system), then doing the ...
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TEME state vector to TLE orbital elements
I was looking at time series of some TLE parameter(semimajor axis, inclination, etc..) and I wanted to how those parameters evolve between measured time points.
So i decided to feed TLE element to ...
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Why ECEF does not coincide with ECI on January 1, 2000 at 12.00? [duplicate]
I assumed that ECEF frame coincides with ECI frame on January 1, 2000 at 12.00.
To see that, on MATLAB, I used the dcmeci2ecef() function as:
...
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How can I calculate GPS satellite's Latitude and Longitude if I have the elevation, the azimuth, the XYZ coordinates of the ground station
How can I calculate a GPS satellite's latitude and longitude if the elevation, the azimuth, and the XYZ coordinates of the ground GPS station are provided?
I have tried these questions:
Computing GEO ...
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Elevation angle for a non-GEO satellite
I want to calculate the elevation angle of a Non-GEO satellite with respect to a ground terminal. The information I have to solve this:
Instantaneous Longitude, Latitude, and Altitude of the non-GEO ...
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How to calculate the ECEF coordinates of a satellite given its elevation and azimuth angle, plus the coordinates of a reference object on Earth
So I am looking for a way to 'reverse engineer' satellite ECEF coordinates given its angles of elevation and azimuth and given the coordinates of an object on Earth serving as a reference ground. The ...
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How to convert TLE data into state vectors in ITRF?
As shown in the question, Now I have a TLE observation data and CPF(Consolidated Prediction Format) data. According to CPF's documentation, CPF predictions are tabulated satellite state vectors ...
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Is this a typo in the Python Skyfield API? "International Coordinate Reference Frame (ICRF)"?
In the Python Skyfield library there is a position object skyfield.positionlib.ICRF, in the documentation it states:
An (x,y,z) position and velocity oriented to ...
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At what point on the Earth's surface does the +X axes of the J2000 coordinate system intersect?
From my newly and developing understanding of the J2000 coordinate system it is defined as the point at which the sun appears to cross the celestial equator from the Southern to the Northern ...
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Where do I find ECEF coordinates of a satellite?
I am taking a university course named 'satellite navigation' as a part of my master degree in aerospace engineering. For the exam we are required to elaborate the coordinates of a LEO satellite (it ...
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Transformation ECI to ECEF acceleration and forces
I know that for velocity conversions between ECI and ECEF there is an $\omega \times r_{ECI} $ term, such that the overall transformation is $v_{ECEF}=v_{ECI}-\omega \times r_{ECI}$. In my belief ...
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