These events occur when the sun, at a low lunar altitude, projects a ray or spike of light, through a broken wall feature of a crater. Although many of these events may be visible on the surface of the moon, these are a listing of the more common ray events which have been reported in astronomical magazines, publications, or from observers who may have detected a ray for the first time, and reported it. Although not of any scientific value, the allusiveness of these events, coupled with the short time frame they are visible, make these real challenges for the avid lunar observer!
If you observe any of these events, and would like to have your observations placed in the reports, or if you think you have discovered another notable ray events, let me know and I will get it published here.
All the past predictions were generated using Harry Jamieson's "Lunar Toolkit" Program. Starting with the new 2021-2030 predictions, Jim Mosher's Lunar Terminator Visualization Tool (LTVT) was used. Besides the Jim Mosher link, LTVT can be downloaded from John Moore's OneDrive page, located at One Drive. Just download all the files and place in the same directory - e.g. C/LTVT and run the .exe file. LTVT uses the JPL DE405 Ephemeris. Searching Jamieson's ToolKit program, it did not specify what ephemeris was being used to genereate the predictions of future events. One will notice if comparing times of the events, they are usually within minutes of each other. Since these events can occur over the span of several hours, the predicted times generated with LTVT should suffice. Also I noticed that using the date and solar altitude over a particular crater, that the solar altitude varied somewhat, but not too far off from the original ToolKit predictions. The difference I felt was also negligible. I also generated these predictions using a geocentric observer, rather than a specific set of terrestial longitude and latitude. When considering observing one of these events, the observer must first determine whether or not the moon will be visible in the sky for their part of the world. Not all events will be visible to everyone on the specifed date. It is also advisable to starting looking an hour or two before/after event time. It is not unusual for an event to occur before or after the predicted time frame.
As time permits, I am going over the initial observations and reports to generate simulations (using LTVT) so that potential observers may know what to expect when observing the ray. I will also add my own comments relating to such ray. Those will be found on the REPORT page.
At the end of the table listing are two files in .ODS and .XLSX format. These spreadsheet files contain two pages. The "RAY BY NAME" page lists all the rays listed alphabetically as found in the online table listing. The "RAY BY DATE" is a listing of all events sorted by date. The files are not locked so anyone wishing to sort/trim to their own needs, can do so. I do ask that if the files are posted on other websites or forums, whether in entirety or a partial listing, that the author be cited as the source.
A word about using the table format: I have not provided links to "back/return" from page to page. Therefore, use the RETURN/BACK button on your browser to return to the previous page. It should also be noted that some browsers do not automatically show the most recent page update. Be sure to use the "reload" button/arrow of your browser to show the most recent page.
If you would like to link to this topic, use the link: http://www.lunar-
You can reach me at: email@example.com (remove the raysat)
Dave Mitsky's Observer's Monthly Observer's Calendar
Updated predictions for 2021-2030
Created 2021-2030 Database of Events Sorted by Date & Time
|ABENEZRA C (needs further investigation)|
|ALPINE VALLEY/MT BLANC (needs further investigation)|
|CALIPPUS (needs further investigation)|
|FRA MAURO HA|
|HALLEY (needs further investigation - could not duplicate)|
|HIND, SE of|
|LAGALLA (needs further investigation)|
|LAME (needs further investigation)|
|PHILOLAUS (needs further investigation)|
|REINHOLD (needs further investigation)|