Funny, I was just using those same sources to calculate sunrise and sunset for Curiosity.<p>I think the latitude for Curiosity is wrong on that Nasa site and in the data file for the downloadable clock they have. I think it should be negative, based on the other sources. I emailed the listed contact to ask.<p>EDIT- Before I found that site, I was working from an ancient clock written in QBasic, described here: <a href="http://www.spaceacademy.net.au/spacelab/projects/marsclok/marsclok.htm" rel="nofollow">http://www.spaceacademy.net.au/spacelab/projects/marsclok/ma...</a>