Several times a year, for a few hours near its first quarter phase, a feature on the Moon called the Lunar X becomes visible in strong binoculars and backyard telescopes.
If skies are clear, point your lenses to the Moon this Sunday, March 1 around 6:52 EST — the Lunar X should be visible.
When the rims of the craters Parbach, la Caille, and Blanchinus are illuminated from a particular angle of sunlight, they form a small, but very obvious X-shape. The phenomenon called is “pareidolia” — the tendency of the human mind to see familiar objects when looking at random patterns. The Lunar X is located near the terminator, about one third of the way up from the southern pole of the Moon (at 2° East, 24° South).
The prominent round crater Werner sits to its lower right.
On Sunday, March 1, the Lunar X is predicted to peak in intensity at 6:52 p.m. EST (or 23:52 GMT) — but the phenomenon will be visible for approximately two hours on either side of that time. This event should be visible wherever the Moon is shining in a dark sky during that time window. Simply adjust for your difference from the Eastern Time zone. For the Americas, the Moon will be positioned in the southwestern evening sky.
Chris Vaughan is a science writer, geophysicist, astronomer, planetary scientist and an “outreach RASCal.” He writes Astronomy Skylights, and you can follow him on Twitter at @astrogeoguy. He can also bring his Digital Starlab portable inflatable planetarium to your school or other daytime or evening event. Contact him through AstroGeo.ca to tour the universe together.