Lunar Observing Schedule for: Latvia - Riga



Produced by the Department of Physics at Aberystwyth University, UK
Ill is percentage illumination of the Moon


2026-May-19 UT 18:55-20:14 Ill=13% Picard

     BAA Request: On 2013 Feb 17 UAI observer: Giuseppe Macalli 
     observed visually an orange cloud form just to the west of 
     Picard crater, and then dissappear. The effect lasted about 1 
     minute. Obviously we are not likely to see whatever this was 
     (?) again under similar illumination, but just for the record 
     it would be useful to have a high resolution monochrome or 
     colour image of this area, at the requested observing 
     time.N.B. an image in the 2018 Jun LSC suggests that the date 
     given of 2013 Feb 17 may have been Feb 18? Please send any 
     high resolution images to: a t c @ a b e r . a c. u k .


2026-May-19 UT 19:34-20:44 Ill=13% Picard

     ALPO Request: Compare the crater in red and blue light - if 
     possible use Wratten 25 and Wratten 38A filters. Please 
     use a telescope of aperture 6 or larger (refractor if 
     possible) and at appromimately x250. Any visual descriptions, 
     sketches, or colour images should be emailed to: 
     t o n y . c o o k @ a l p o - a s t r o n o m y . o r g


2026-May-20 UT 19:41-20:19 Ill=22% Earthshine: sporadic meteors

     These can only be observed using low-light level cameras running at 25 frames per sec,
     or faster, and capable of recording 9th or 10th magnitude stars in real time.
     Dates/UTs of observing runs, or detections of impacts, should be emailed to:
     ALPO - email: c u d n i k @ s b c g l o b a l . n e t
     BAA - email: a t c @ a b e r . a c . u k
     UAI - email: a m . 5 4 8 5 2 @ g m a i l . c o m


2026-May-21 UT 19:43-20:47 Ill=33% Earthshine: sporadic meteors

     These can only be observed using low-light level cameras running at 25 frames per sec,
     or faster, and capable of recording 9th or 10th magnitude stars in real time.
     Dates/UTs of observing runs, or detections of impacts, should be emailed to:
     ALPO - email: c u d n i k @ s b c g l o b a l . n e t
     BAA - email: a t c @ a b e r . a c . u k
     UAI - email: a m . 5 4 8 5 2 @ g m a i l . c o m


2026-May-22 UT 19:46-21:05 Ill=44% Earthshine: Camelopardalis: ZHR=? (vel=16 km/s)

     These can only be observed using low-light level cameras running at 25 frames per sec,
     or faster, and capable of recording 9th or 10th magnitude stars in real time.
     Dates/UTs of observing runs, or detections of impacts, should be emailed to:
     ALPO - email: c u d n i k @ s b c g l o b a l . n e t
     BAA - email: a t c @ a b e r . a c . u k
     UAI - email: a m . 5 4 8 5 2 @ g m a i l . c o m


2026-May-23 UT 20:08-21:49 Ill=54% Ukert

     Ukert: a "V" on the Moon - this is a Clair-Obscur effect. 
     Clair-Obscur have no scientific importance and are just tricks of the 
     light that make us think we see something like a letter of the alphabet 
     or a shape or face. Clair-Obscur effects are scientifically pointless 
     to observe. However, if you want to be thrilled, or obtain an image to 
     impress someone then give them a go. If you do observe, or image this, 
     by all means send your observation into ALPO or the BAA, but we 
     probably won't publish, but will nevertheless retain in our archives, 
     just in case features elsewhere in the image are of interest to 
     future researchers.


2026-May-23 UT 20:08-21:49 Ill=54% Werner

     Werner: an "X" on the Moon - this is a Clair-Obscur effect. 
     Clair-Obscur have no scientific importance and are just tricks of the 
     light that make us think we see something like a letter of the alphabet 
     or a shape or face. Clair-Obscur effects are scientifically pointless 
     to observe. However, if you want to be thrilled, or obtain an image to 
     impress someone then give them a go. If you do observe, or image this, 
     by all means send your observation into ALPO or the BAA, but we 
     probably won't publish, but will nevertheless retain in our archives, 
     just in case features elsewhere in the image are of interest to 
     future researchers.


2026-May-23 UT 19:48-21:14 Ill=54% Earthshine: Camelopardalis: ZHR=? (vel=16 km/s)

     These can only be observed using low-light level cameras running at 25 frames per sec,
     or faster, and capable of recording 9th or 10th magnitude stars in real time.
     Dates/UTs of observing runs, or detections of impacts, should be emailed to:
     ALPO - email: c u d n i k @ s b c g l o b a l . n e t
     BAA - email: a t c @ a b e r . a c . u k
     UAI - email: a m . 5 4 8 5 2 @ g m a i l . c o m


2026-May-24 UT 21:30-21:53 Ill=65% Plato

     BAA Request: It has been noticed that a bright carterlet can 
     appear very suddenly on the floor of Plato in between needle 
     like shadows, during local lunar sunrise. This happens in the 
     space of just a minute or so, and can look really quite dramatic.
     This effect was first spotted by Brian Halls on 2014 Oct 31 
     Please send any high resolution images, detailed scetches, or 
     visual descriptions to: a t c @ a b e r . a c. u k .


2026-May-25 UT 20:57-21:04 Ill=74% Copernicus

     BAA Request: On 2012 Sep 24 E. Horner noticed a very strong red 
     colour around part of the sunlit inner rim of Copernicus, 
     sometimes a 1/4 and sometimes 1/2 around the interior. Quite 
     likely this was some form of atmospheric spectral dispersion - 
     though the observer checked for similar effects on other craters 
     but saw none. But to be sure we would like to obtain some colour 
     images or visual observations of this crater. The minimum sized 
     telescope to be used would ideally a 6" reflector. Low elevation 
     angles for the Moon are ideal as we want to try to replicate 
     this effect if it is indeed due to atmospheric spectral 
     dispersion. Please send any high resolution images, detailed 
     sketches, or visual descriptions 
     to: a t c @ a b e r . a c. u k .