Celestia Forums

Not sure where this message should go because I'm trying to use Celestia for a very strange objective and I'd appreciate any advice, pointers or changes!

I'm trying to determine the lunar coordinates that a space observatory (Chandra) would be pointing at at a specific time in the past based on the RA and Dec of its pointing.

I appreciate this is an extreme request, but I know the RA and Dec, the time of the observation and the ephemeris of Chandra and the moon. I need to know if Celestia could produce a lunar coordinate based on an RA and Dec from Chandra.

Any responses or suggestions are helpful - you'd be contributing to genuine scientific research!

Nick

Nick,

If I've understood correctly what you're asking, then Celestia can do it. But, you'll need to write a small script and may want SPICE kernels or the DE405 ephemeris for very accurate positions of the Moon. By 'lunar coordinates', do you mean the longitude and latitude on the surface of the Moon? Are you already using a SPICE kernel for Chandra?

--Chris

Hi

Thanks for getting in touch, I'm currently using the Chandra model the Celestia Motherlode, but if there is something more accurate that would be better. Where can I find SPICE kernels for Chandra and the moon?

Lunar longitude and latitude would be perfect, but any clearly defined coordinate system would be fine if I could then convert to longitude and latitude.

Nick