I was able to get a few good photos of the Moon/Venus/Jupiter conjunction last Monday, but mostly by good luck, and some educated guessing.
I would like to take a more rigorous approach in the future. I known where I want to stand (33.508512, -111.96133), and the bearing I want to aim for (~236° 52’). What I want is an automated way to calculate when a full moon is setting close to that bearing.
I have the GPL programs Celestia and Stellarium, if that helps.
Any idea how I automate this?
I don’t know about automating this…but since the full moon only sets once per month, I found it straightforward to skip ahead in Stellarium and look at the azimuth (bearing) of the setting full moon for each month until it was close to 236°.
Now, of course, you don’t get to pick any arbitrary bearing for a moon rise or set. You happened to pick one that was within the possible range of azimuths near due West where the moon can set. Perhaps you knew that already, but I wanted to make it clear to the audience that this doesn’t work for any bearing you can name.
Turns out that on the morning of May 9, 2009, the setting full moon will be quite close to where you want. At 07:55 local time, the moon will be at 237° and 5° above the true horizon. I don’t know about your vantage point, but I can’t see 0° because of rolling terrain. If you can see all the way to 0° elevation, the moon will be at 241° azimuth about half an hour later. And at 10° up in the air, it will be around 232° a half-hour earlier.
As far as automation, I can’t help you there. I’m sure it can be done, but I don’t have the tools.
Thanks for your help.
I’ve only played with Stellarium a little - I’ll have to try it some more.
It sure would be nice if there was a way to script it (although I suppose I could just manually plug in the dates for full moon sets).
The reason I picked that bearing is that puts the few tall buildings in Phoenix in front of the Moon from this nice high spot on a mountain about 8 miles away.
Thanks.
I was hoping to capture the triad setting behind the buildings downtown, but the distance between the moon and the two planets was far too great - the planets set almost an hour before the moon did. I’m hoping to get a shot of the full moon setting by itself, which is why I posted the question.
I can’t help you either, I just wanted to chime in and say, “great shot!” We have family down in Mesa, and this makes me nostalgic. I was there for Hale-Bopp in '97, too.
An ephemeris will give you the coordinates of a celestial body at some particular time, but the OP can already get that from programs like Celestia (which, of course, has ephemeris calculations built in). He’s looking for the reverse problem, finding a time when a celestial body will be at particular coordinates, and I’ve never heard of a simple formula for that (other than just stepping through and trying all of the times).
There’s also a question of the precision required. In the OP’s case, you probably have some amount of freedom in not just the optimum angle and vantage location, but also in the phase of the Moon: The picture will probably look just as striking a day or two away from full, which opens up the possibilities of when to get the picture.
Update:
I remembered I had this page bookmarked: Sun and Moon Rise and Set Azimuth
Although it’s not automated, the unlocked version ($15) will output a table with the information I need. It should be easy to massage in a spreadsheet to extract the full moon rise/set and azimuth data. I’m going to spend the $15 and try it.
