Ganymede Totally Occults Europa - May 18

[Centaur]

I predict that for North Americans during Monday morning 2009 MAY 18, Jupiter’s Galilean satellite #3 Ganymede will totally occult #2 Europa. This will be a nighttime event out west and a daytime event in the east.

#3 Ganymede Occults #2 Europa
2009 MAY 18 PDT (UT-7)

04:39:30 PDT Partial Occultation Begins
04:42:34 PDT Total Occultation Begins
04:43:20 PDT Minimum Separation of Centers
04:44:08 PDT Total Occultation Ends
04:47:12 PDT Partial Occultation Ends

I’ve created three related graphics previewing the event. They can be seen at: http://www.curtrenz.com/astronomical.html

Photos, descriptions and timing verifications would be welcome additions to this thread.

[grant hutchison]

An image (http://www.ghutchison.pwp.blueyonder.co.uk/orbits/ganeur.jpg) of the same event from Celestia.

Grant Hutchison

[Centaur]

An image (http://www.ghutchison.pwp.blueyonder.co.uk/orbits/ganeur.jpg) of the same event from Celestia.


The Celestia diagram is quite similar to mine, Grant, but seems to indicate that the 50% diameter coverage during the late stage will happen more than three and a half minutes earlier than I predict. It will be interesting to see who is correct after actual observation. Sky & Telescope gives times for the beginning and end of the partial stages that are very close to mine, although they provide no data for the other stages. I use the high precision algorithm of Jean Meeus in his book Astronomical Algorithms. My figures are for San Francisco (not geocentric), but should not vary by much more than a second or two for other locations.

[grant hutchison]

Yes, the distribution package of Celestia comes up about three minutes different from your calculations.
I suspect that if I loaded high-precision orbits the Celestia timing would move closer to yours. :)

Grant Hutchison