While testing a telescope in Summerland, B.C. on Monday, April 22, Dave Gamble noticed an unusual feature on the lower terminator of the 12 day old Moon. Applying 405x he was amazed to find a dramatic pattern of isolated sunlit hilltops that one could imagine was a mouthful of very bright teeth which prompted the descriptor. It was unlike any lunar feature he had ever seen or heard of.
The age of the Moon was determined to be 12 days 19.166 hours, however Alister Ling noted that colongitude was a better guide than age and he found it was 61.7 for the time of the observation. Alister calculated the time of the same colongitude with the respective Sun latitudes in coming months and they are included in this gallery.
This is likely quite an ephemeral event that would only be visible for a matter of hours.
The next best opportunity to revisit the event since that time was on October 16 when a series of photographs of the area were taken at 15 intervals, beginning at 5.45pm and continuing until 11.30pm. The predicted colongitude time was 7.03pm, however even at the time of the first observation at 5.45pm the scene seemed to be too advanced.
Also in this gallery is an overview picture of the Mersenius region adjacent to Mare Humorum which was supplied by Alister.
It would be appreciated if your observation reports and images could be shared with Dave Gamble at firstname.lastname@example.org and Alister Ling at email@example.com. If you wish they can be included in this clearinghouse gallery.