Questions tagged [spice]
The SPICE is a information system released by the Navigation and Ancillary Information Facility (NAIF) to assist scientists and engineers. The system includes data sets called "kernels" and the SPICE Toolkit, a software library needed to read the kernel files and to calculate observation geometry parameters of interest to scientists and engineers.
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rebound + SPICE (scipy) simulation produces highly inclined lunar orbit
I am using the python rebound library with SPICE data to simulate the solar system. Below is a full script which simulates the solar system for 1 year beginning at 2000, and here is the ...
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Calculating relative position of JUICE for observer at given coordinates with SPICE
My antenna is at coordinates: LATITUDE = 47.397490, LONGITUDE = 8.550440 I want to calculate azimuth and elevation of JUICE with SPICE. This is what I have so far: ...
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SPICE can't find path with meta kernel
I'm trying to load kernels with a meta kernel but I get this error message. ...
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Incorrect limb points from SPICE 'limbpt' routine?
I'm encountering a baffling problem with the SPICE routine limbpt (as implemented in SpiceyPy) and I'm not sure how to fix it, so I'm hoping one of you might know ...
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What does w.r.t. mean? I've found it in the summary of jup365.bsp [closed]
Inside summary of the file jup365.bsp I have found this: ...
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Obtain all the points of the orbit of a celestial body in the solar system
How can I render (or plot) the orbit of a planet using SPICE? Sorry, I'm not English and I don't know how to say to draw the path that the planet follows around the Sun (their orbit or, maybe, ...
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Which SPICE kernels I have to load to calculate state vector of the outer planets
I'm developing a software to show the planets in the sky. I have loaded the following kernels: ...
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1answer
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Computing viewing geometry of Solar System targets from ground-based observatories using SPICE kernels
SOLVED. I want to calculate the visible part of an asteroid (I'll use the Moon in this example) from the Chile VLT observatory (latitude, longitude coordinates = -24.62733, -70.40417). On the NAIF ...
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Beginner to simulating communications systems of space missions. I have GMAT, MATLAB and NASA's SPICE library. Where would I start?
I recently managed to load SPICE kernels into GMAT to simulate the trajectories of real missions, and got its MATLAB interface working (still trying to understand how to use the two software together)....
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1answer
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Different Earth-centered ICRF positions in GMAT and Skyfield/Spiceypy with DE421
I compared the Earth-centered positions from the Moon in the ICRF (i.e., in GCRF) using three different sources: SpiceyPy (https://pypi.org/project/spiceypy/) Skyfield (https://rhodesmill.org/...
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How to compute light time correction for eclipse entry/exit timings?
I used a typical geosynchronous orbital parameters and generated lunar shadow penumbra entry and exit timings using OREKIT and GMAT. GMAT has an option to include light-time correction (also for ...
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Why does Earth's North Pole RA flip by ~180 deg around AD2000 relative to SSB? (JPL Horizons data)
Using JPL's Horizons API I see that the Earth's North Pole RA flipped by ~180 degrees quite suddenly around AD 2000. It was pretty stable around 180deg for at least 1000 years prior, and then remains ...
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Where to get data for axis of rotation of solar system bodies?
Where can I get data for the axis of rotation of the (major) bodies of the solar system? For each solar system body, I want to get a unit vector of its axis of rotation (at a specified point in time). ...
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Osculating conic orbital elements: Comparing SPICE's oscelt to MATLAB's ijk2keplerian functions
I have been using the SPICE Toolbox and wanted to derive orbital elements from a state vector $X$ in ECEF coordinates [1] in order to define a circular orbit around Earth. To do so I need first ...
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Change frame center definition of Chebyshev coefficients
I am using SPICE to read and store Chebyshev coefficients to then compute position of Solar System bodies in my navigation software (see this post). The coefficients are defined with respect to the ...
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