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I'd like to calculate the distance between the Earth and an asteroid at a given date. Is this possible using the data from JPL's small-body database? Is there a better way?

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By "calculate", would you be satisfied with a website that does the calculation for you? A number of sites offer this, JPL's for example is Horizons. – Sonia Apr 26 '12 at 15:19
Thanks, this is really helpful. Please forgive my ignorance, but I want to confirm that 'delta' is the measurement I am interested in (in AU). Is there some reading I can do to understand how the underlying calculations are performed? – ty. Apr 26 '12 at 21:35
Ah, nevermind, the telnet solution has a lot more flexibility. Thanks. – ty. Apr 26 '12 at 22:00
Yes, I believe delta is what you want. There should be an explanation right in the returned results, following the table, and of course there is documentation on the whole system. Also, as you may have noticed, the "Ephemeris" on the small-body page you linked above takes you straight to Horizons with the object filled in from the small-body database and other fields still set from the last way you used them. – Sonia Apr 26 '12 at 23:42
Similarly to what Sonia said, there are a number of programs that will help you with this - most planetarium software. Celestia, Stellarium, and KStars are some (Free and Open-Source) examples. – hunter2 Apr 1 '13 at 12:01

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