Google Sky Integration

We’ve all used Google maps to get around. Google maps can also overlay aerial photographs, and you can link to Google Earth to see pictures at street level.

Google also has Google sky that allows you to view the stars. I fooled with this briefly when it came out and didn’t get anywhere with it. I was able to use the Google Earth API to make Points-of-interest files for my GPS device. I finally got Google Sky working correctly with FreeNameAStar.com.

Here is the secret. Instead of Longitude and Latitude, you have to use the sky equivalents of Right Ascension and Declination. The Sky coordinates start at zero at the Vernal equinox. The big difference in Google Sky, is that it uses a view as though you were looking down at earth so the Right Ascension is the mirror image of the standard astronomical right ascension.

I have to convert the radians stored on the database into degrees, and then I have to subtract the right ascension from 180, giving it backwards from the vernal equinox. Pretty tricky!

I now embed an actual photograph of the star from Google Sky in each Star’s web page.