A few Afocal Lunar Images

[Ragilmer]

I got out early yesterday morning for a pre-dawn observing session with my son and ended it by getting some afocal iPhone photos through my AD10 (reported over here viewtopic.php?f=6&t=27115 ). I've been wanting to learn lunar geography a little better, so I thought a good way to do that would be to look up some information about each of the landmarks or features I photographed. If I'm incorrect on any of my ID's I'd appreciate the corrections as I'm still learning my way around.

The Kepler crater in the first photo is about 20 miles across and 1.5 miles deep. The rays coming out of blast site span almost 200 miles

The horseshoe shape at the bottom of the image is the Bay of Rainbows (Sinus Iridium). It’s about 150 miles across and is an impact crater that was flooded with lava. It’s ringed by the Montes Jura which top out at over 12,000’ higher than the “bay” below.

Mare Humorum (Sea of Moisture) is a little over 250 miles across and is ringed by craters. The prominent crater on the right of the sea is called Gassendi and makes a jeweled ring shape with Gassendi A, the smaller crater at the top of the loop. You can also make out the central peaks left over from the initial blast.

In the center of the next image is the crater Vitello (the dark, oddly-shaped crater). It was once thought to be a volcano, but lunar missions helped show that it had no contemporary volcanic activity (and likely is just a weirdly shaped crater). This image was made in Lynkeos by stacking about 10 separate frames. Mainly I was messing around with it to try and remember how to stack images If anyone has suggestions on better Apple compatible stacking software please let me know. I was just using still images, but next time I may try to use some video clips to stack instead.

I haven’t been able to find a name for the cool valley on the center right. I just like the shadow cast by the mountains on the opposite side of the valley from us. Does anyone know what that feature is called?

The large crater in the center (above Vitello and the cool valley) is named after Wilhelm Schickard, a 17th century German professor who studied classical languages of the Levant and astronomy. He also invented an early mechanical calculator—but it didn’t quite work, which is why you may not have heard of him (I don't think I had before I looked up the crater ).

Thanks y'all!
-Rob

[pakarinen]

I got out early yesterday morning for a pre-dawn observing session

My favorite time to observe unless I'm out at a dark site.

I haven’t been able to find a name for the cool valley on the center right. [...] Does anyone know what that feature is called?

If I'm looking at the same feature as you, that's Schiller crater - the oblong thing.

[Ragilmer]

Thanks Pakarinen! I think that is probably it. So did the impact come in at an angle to cause that shape?

Screen Shot 2022-09-21 at 8.37.59 AM.png (76.69 KiB) Viewed 517 times

[pakarinen]

Thanks Pakarinen! I think that is probably it. So did the impact come in at an angle to cause that shape?

You'd think so, but I'll defer to the lunar experts among us.

[jrkirkham]

Thanks for posting this set of shots. I always like good lunar shots.

[MrShorty]

Some very nice lunar shots, thanks for sharing.

If it's not too forward to add additional interest to these pics. In your shot of Kepler, you can follow one ray up and a little to the right to get to crater Reiner and that kite shaped white patch that is simply called Reiner Gamma. These so-called "lunar swirls" (Reiner Gamma is the easiest one to view from Earth) can be very interesting, in part because no one really knows what they are.

Towards the top of the "bay of rainbows" pic is the highest albedo feature on the near side of the moon -- crater Aristarchus. An interesting observation challenge near Aristarchus is to get a good look at Vallis Schroteri -- a prominent, winding valley in the plateau.

Thanks again for the lunar pictures. It really can be a lot of fun to get to know our nearest neighbor.

[messier 111]

nice , thx .