32 replies to this topic

[wargrafix]

I am preparing a high resolution capture

[BillHarris]

The extreme librations for M.Orientale are in 2021 and 2027. Has anyone calculated "acceptable" librations or even "totally useless librations" where that limb is rocked all the way West?
Or other limbs, like the Eastern limb, or North South limbs?
I'm getting ready to delve into the Limbo of Libration to try to peak over the edge of the Moon, and I don't want to reinvent the Wheel if someone's already done that. The chart that Tom posted is an awful lot of work!

[Tom Glenn]

The extreme librations for M.Orientale are in 2021 and 2027. Has anyone calculated "acceptable" librations or even "totally useless librations" where that limb is rocked all the way West?
Or other limbs, like the Eastern limb, or North South limbs?
I'm getting ready to delve into the Limbo of Libration to try to peak over the edge of the Moon, and I don't want to reinvent the Wheel if someone's already done that. The chart that Tom posted is an awful lot of work!

Bill, I posted in another thread a table that includes time intervals that meet a criteria of librations of 5 degrees (combined) or more for the Orientale basin.  This value is based upon an image I took several years ago that met these criteria but was not as favorable as the period we just experienced, yet allowed for many interesting features to be observed.  I have not conducted a study on "totally useless" librations, although this could be done.  LTVT can be used to produce libration tables for any region with any constraint desired.  

 

[BillHarris]

Thanks, Tom. That gives me a start.
I've always been fascinated by the deeply-shadowed views near the limb.

[payner]

I am late to this thread, but wow, outstanding images and information, Tom. I was fortunate to catch a S&T article describing the very favorable libration of November 27 & 28, 2021 -- bonus, the weather cooperated. I was able to observe all but the most extreme features in your excellent images. I used a 130 mm Apo, f/7.7 at various magnifications.

Glad I came across this thread. Thanks.

[Special Ed]

Hi Tom,

 

I read Bob King's article about Mare Orientale and saw your excellent images there and then saw this thread.  The MO region is probably my most favorite feature on Luna.  I'm like a moth to a flame whenever I see anything about it.     I have observed and sketched it several times.

 

I looked at that table you provided in post #18 with interest.  I observed MO on July 14th and 15th, 2009 during one of the very favorable librations on that list.  Over the two days, I made this sketch (and an annotated version).   It was a real thrill to see the top of the Rooks on the far side of the mare.  I hope you don't mind if I post it here.

 

 

[Tom Glenn]

Thanks Bill, Randy, and Michael for the additional comments.  I'm glad to hear that some people came across Bob's excellent Sky & Telescope article.  Judging from some comments I have seen on this forum, as well as below the article itself, it appears that multiple people were able to view the Orientale region because of the article, and hopefully the article and images helped in their enjoyment.  It is a bit of a shame that we are so late in the "season" for the Orientale basin, as the window of the best librations has somewhat passed us by, although there are still several opportunities for favorable views in the coming year.  The seasons of maximum libration occur every 6 years, although they usually occur in conjunction with another very strong season in an adjacent year, as was the case recently with both the fall of 2020 and 2021 having very favorable views.  The weather did not cooperate for me in 2020, but I was lucky that it did cooperate in 2021 during the even stronger libration.  

 

Michael, thanks for sharing your excellent sketch!  It shows outstanding detail, and is fun to match up with my image.  When I submitted my image to APOD, I also created a slightly larger crop than the one originally posted here, with a few more labels in the region that can be found here (also reproduced below).  

 

[PCW]

Mare Orientale 17.3.2022 time 19.10-19.20 UT. Finland, Vantaa (near Helsinki-Vantaa airport).

 

It is BTW great change to observe this also in now November and December.

 

 

 

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