A user seeks an accurate barycentric solar system ephemeris to obtain state vectors for the sun and planets. The JPL Horizons website is recommended as a suitable resource, allowing users to input time and retrieve necessary data. For barycentric coordinates, the observer location should be set to @0, while @010 is for heliocentric. While heliocentric data is noted as more useful by some, barycentric data is preferred for specific calculations like angular momentum. The discussion emphasizes the importance of using barycentric coordinates to avoid adjustments for solar wobble.
Does anyone know of a website with an accurate ephemeris where you can plug in a time and get the state vectors (position and velocity) for the sun and all of the planets in a barycentric coordinate system?
For observer location, use @0 for barycentric or @010 for heliocentric.
There won't be a huge difference between the two.
I find heliocentric more useful.
Thanks for the tip. I need barycentric because I am calculating angular momentum and I don't want to have to adjust things for the wobbling of the sun.
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20250922, 0701NZST
Canon 6D II 70-200mm @200mm,
F4, 100th sec, 1600ISO
Makeshift solar filter made out of solar eclipse sunglasses
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