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bkm2304
15-09-2024, 10:03 PM
Hello all,

Well I have a (temporary) piece of concrete under the shed roof to set up the scope. I can only see 60 degrees up in the east which is better than nothing!

Sinus Iridum taken on the 14th September. The interesting thing about the two promontories - Heraclides and Laplace - is that they differ in height dramatically. Laplace is over 3000M high while Heraclides comes in at 1800M. This goes to show how "unlevel" craters can be. Also possibly explains why half the thing is missing under lava.

The two wrinkle ridges which look like waves about to break on the inner shore of Iridum are high also. The ridge below Bianchini boasts a spot height of 360M - a fair hike for any astronaut even at 1/6 G.

3000 frames stacked in AS!3 and processed with Registax, Focus Magic and Astro Art. Celestron 14"HD, ZWO 178mm camera, Red filter.

Richard

Dave882
16-09-2024, 12:20 AM
Nice images Richard, and great to see you've been able to get the c14 out!!
I don't know how many times I've looked at that / imaged it - but sometimes you forget the scale of things. I can't believe that wrinkle is 360m!!
Thanks for posting

Tinderboxsky
16-09-2024, 10:13 AM
Yes, great image, Richard.

Whilst the wrinkles are about 360m high, I thought they are many kilometres wide. That would mean they are very slight inclines to climb. The slope would be almost undetectable. I could be totally wrong on this!

Views with these wrinkles casting shadows show them the in stark relief.

Saturnine
16-09-2024, 12:27 PM
Hi Richard. Is always good to see your images. Iridium is always enticing when near the terminator and always interesting with the variations in lighting angles on the wrinkles, promontories and craters.

bkm2304
18-09-2024, 11:33 AM
Yes, Steve. Good Point. You've got me thinking about this.

If you look at the measured slope on the LAC Series Lunar Map for S Iridum it shows a measured slope of about 5km. A 360M drop over this distance is about a 7% gradient - Le Tour fans will know this is a semi-serious slope to climb.

So I suppose this is a pretty steep section given the distance measured down to the floor of the sinus.

Richard.

Tinderboxsky
19-09-2024, 01:42 PM
Interesting numbers, Richard.

They are intriguing structures and there are so many of them across the lunar surface to explore as the lighting changes over time.

astronobob
25-09-2024, 08:11 PM
Nice shootin Richard, very smooth, almost too smooth, making me think a 7% grad would not be enough for a sand toboggan, looks a better slope from Bianchini down the the crater floor would be hoot