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HuginandMunin
Posted: Tue Jun 24, 2008 3:13 pm
Joined: 24 Jun 2008 Posts: 1

Converting celestial coordinates to a point on earth?






Hello,
I have a set of celestial coordinates that I'd like to convert to latitude and longitude (i.e. a spot on earth). Could someone explain to me how this conversion is done? Is there an online utility that could perform the conversion? Or is this going to require some serious math on my part?
The celestial coordinates I have are: RA 288.853454589844 DEC 42.3792304992676
The solution should end up somewhere around N 42° 2x.xxx W 071° 0x.xxx.
For anyone interested in why I want to do this, it's a geocaching puzzle. Once I figure out the earth coordinates (that match the above celestial coordinates) I will go to that location and hopefully find a geocache.
Any help with this would be greatly appreciated!


quasar
Posted: Thu Jul 24, 2008 5:34 pm
Joined: 24 Jul 2008 Posts: 14



You need some trigonometry. I'll provide you 3 formulas, but after one day because I need to type some special characters. It's about transformation from equatorial to geographic coordinates: longitude and latitude.
Prepare to solve a 3 equation system with 3 parameters.
See you tomorrow...
best regards,
Dan Romania


bodybagger
Posted: Thu Aug 05, 2010 8:44 pm
Joined: 05 Aug 2010 Posts: 1



These are not real celestial coordinates. You can't transfer celestial coordinates to the Earth's surface without knowing the hour angle of the first point of Aries (the vernal equinox). However, since these are obviously not celestial coordinates and are in a terrestrial pseudocelestial coordinate system, assume the first point of Aries lies at the prime meridian This puts the coordinates near MIT (just as you suggested). What do you want to bet an MIT brainiac hid this? It's simple arithmetic from here  no spherical trigonometry involved whatsoever. If you can't figure it out from here, you probably weren't meant to find it.


