First quarter moon falls at 21:20 UTC on April 27, 2023
Lunar X and Lunar V
Have you ever heard of Lunar X and Lunar V? They’re well-known optical options on the moon, seen by telescopes. So when the moon’s terminator – or line between gentle and darkish on the moon – is situated in simply the precise place, you possibly can see a letter X and a letter V on the moon’s floor. An indication of an alien visitation? No. Lunar X is a superb instance of how lighting and topography can mix on a planet or moon to supply a sample that appears acquainted to the human eye.
In actuality, the phantasm of Lunar X is created by daylight falling on the edges/ridges between the craters La Caille, Blanchini, and Purbach. The V is attributable to gentle illuminating crater Ukert, together with a number of smaller craters.
When are they seen?
Principally, folks see Lunar X and Lunar V at every cycle of the moon, however just for a short while. In reality, they’re observable for about 4 hours across the 1st quarter moon phase.
Backside line: Lunar X and Lunar V are optical options on the moon, seen by a telescope for a number of hours across the time of the first quarter moon.
