People In North America Will See A Giant X On The Moon This Thursday – IFLScience
CLOSEWe have emailed you a PDF version of the article you requested.Please check your spam or junk folder You can also addnewsletters@iflscience.comto your safe senders list to ensure you never miss a message from us.CLOSEComplete the form below to listen to the audio version of this articleListenCancel and go backIFLScience needs the contact information you provide to us to contact you about our products and services. You may unsubscribe from these communications at any time.For information on how to unsubscribe, as well as our privacy practices and commitment to protecting your privacy, check out ourPrivacy PolicyAdvertisement ACCOUNTSIGN INSIGN OUTSearchBecome anIFLScience memberMY ACCOUNTTHE VAULTMY ACCOUNTTHE VAULTMAGAZINESIGN OUTJames FeltonJames FeltonSenior Staff WriterJames is a published author with four pop-history and science books to his name. He specializes in history, strange science, and anything out of the ordinary.BookView full profileBookRead IFLScience Editorial PolicySenior Staff WriterMaddy ChapmanEditor & WriterMaddy is an editor and writer at IFLScience, with a degree in biochemistry from the University of York.BookView full profileBookRead IFLScience Editorial PolicyDOWNLOAD PDF VERSIONThe lunar X appears along the terminator line between day and night.Image credit: MitchellLens/Shutterstock.comDOWNLOAD PDF VERSIONIf you look up at the Moon this Thursday through binoculars or a small telescope, you may be able to see an unusual feature; a giant “X” on the lunar surface. If you scan your eyes along the terminator line, you may also see a temporary “V” on the Moon, too.ADVERTISEMENTEvery body orbiting the Sun has a terminator. That’s the line that divides the day side and the night side of the body in question, rather than a killer robot from the future played by the guy from Kindergarten Cop. The Moon is no exception, and the line gives us an opportunity to figure out its three-dimensional shape.”The lunar surface appears different nearer the terminator because there the Sun is nearer the horizon and therefore causes shadows to become increasingly long. These shadows make it easier for us to discern structure, giving us depth cues so that the two-dimensional image, when dominated by shadows, appears almost three-dimensional,” NASA’s Astronomy Picture of the Day website explains.”Therefore, as the Moon fades from light to dark, shadows not only tell us the high from the low, but become noticeable for increasingly shorter structures. For example, many craters appear near the terminator because their height makes them easier to discern there.”During the first quarter phase, for around an hour, there are some particularly interesting shadows on the lunar surface. Or at least, they appear interesting from our perspective, as they look suspiciously like the letters V and X to human minds looking for such patterns. “The Werner X does not leap out all at once but gradually appears over an interval of 2 hours and 20 minutes as the Sun rises on the spot,” David M.F. Chapman of the Halifax Centre of the Royal Astronomical Society of Canada explains in a piece on the topic, after capturing images of the X.ADVERTISEMENT”Out of the blackness, the Sun’s rays first catch the tallest point: this turns out to be a peak on the SE wall of Purbach [crater]. This point lengthens into an arm in the NNE direction towards the common area between Purbach, La Caille, and Blanchinus [craters]. Meanwhile, the NE wall of Purbach becomes illuminated and they join to form a corner. Next, the SW wall of Blanchinus catches the light and we see a ‘T’. Finally, the common wall between Blanchinus and La Caille form a NE arm which joins the rest to form the X.”On Thursday, March 6, you should be able to get your own view of the X and V, as the terminator aligns just right with the various features on the Moon. In terms of how to find it, it is easiest to look for the X itself along the terminator line, rather than identifying the craters first. The X should begin to emerge at around 11 pm UTC, and will be visible for around an hour.Should you miss it, or should you be in an area of the world where the Moon is not visible at that time, fear not. The X and V appear regularly throughout the year, with your next opportunities happening on April 5 and June 3.moon,USA,terminator line,North America,Astronomy,amateur astronomy,lunar phases,lunar x,lunar vlink to articlelink to articlelink to articleAdvertisement Advertisement Advertisement link to articlelink to articlelink to articleReceive weekly science coverage direct to your inbox© 2025 IFLScience. All Rights Reserved. RSS
