by Chris Peterson » Tue Jan 18, 2011 9:26 pm
Philosophaie wrote:I have developed a program calculating the orbits of the planets from Jet Propulsion Lab (JPL) data.
I am in need of the actual data of the planet's orbits for specific dates:
Argument of the Perihelion
True Anomaly
Mean Anomaly
Semi-Major Axis
Eccentricity
Longitude of the Ascending Node
etc
If someone could give me the name of some sort of book or almanac it would be much appreciated.
I'm not sure what you're asking for. Orbital elements are not a function of time, although unstable elements are periodically updated. Planetary elements are very stable, however. Are you simply looking for the values of the six classical Keplerian elements (which would not be strictly associated with any particular time), or are you looking for actual state vectors for the planets at specific times so you can test your propagator?
The classical elements for the planets are available
here, valid with a small error for 3000 BCE to 3000 CE. If you need more accuracy in your calculations, you should not be using Keplerian elements at all, but a more complex system, using either series with many terms or dynamic integration.
If you're looking for orbital state data, I'd suggest the JPL
Horizons propagator, which will provide much more accurate output than any Keplerian approach can.
[quote="Philosophaie"]I have developed a program calculating the orbits of the planets from Jet Propulsion Lab (JPL) data.
I am in need of the actual data of the planet's orbits for [u]specific dates[/u]:
Argument of the Perihelion
True Anomaly
Mean Anomaly
Semi-Major Axis
Eccentricity
Longitude of the Ascending Node
etc
If someone could give me the name of some sort of book or almanac it would be much appreciated.[/quote]
I'm not sure what you're asking for. Orbital elements are not a function of time, although unstable elements are periodically updated. Planetary elements are very stable, however. Are you simply looking for the values of the six classical Keplerian elements (which would not be strictly associated with any particular time), or are you looking for actual state vectors for the planets at specific times so you can test your propagator?
The classical elements for the planets are available [url=http://ssd.jpl.nasa.gov/txt/p_elem_t2.txt]here[/url], valid with a small error for 3000 BCE to 3000 CE. If you need more accuracy in your calculations, you should not be using Keplerian elements at all, but a more complex system, using either series with many terms or dynamic integration.
If you're looking for orbital state data, I'd suggest the JPL [url=http://ssd.jpl.nasa.gov/horizons.cgi]Horizons[/url] propagator, which will provide much more accurate output than any Keplerian approach can.