For you morning people out there, right now the Moon is rising as a narrow crescent just before the dawn. Every day until May 11, it will rise a little closer to sunrise and will appear ever so much thinner. This means now is your chance to really enjoy looking at faint things like the band of the Milky Way as it stretches across the sky. 

For those celebrating Ramadan, this tiny sliver of the Moon means Ramadan is almost over. Next Tuesday, at 3:01 pm Eastern time, the Moon will be located on the same plane as the Sun and the Earth, and we will be unable to see it in the sky. As it orbits, it will slowly begin to be illuminated on its other edge, as seen from Earth, and once the illuminated edge is seen, Ramadan will end. This means observatories across the Muslim world will be watching closely for that hour’s old moon to be visible. 

For people of all cultures, the race to see just how young a new moon can be spotted to the west of the Sun is an astronomical challenge worth accepting. To see it, you have to point your telescope during the day at the spot the Moon should be located and make out the faint crescent against the bright blue sky. I personally have never seen a Moon younger than a day, but in 2002, Mohsen Mirsaeed spotted an 11-hour, 40-minute old Moon on Sept 7, 2002, using binoculars, setting a new record.

Observing the Moon is something we do for many reasons. It’s there and it’s pretty is a perfectly sound reason and is part of why I like trying to photograph the Moon against the horizon. The Moon is also scientifically interesting as it formed, we think, through the collision of the Earth and another object we call Theia. The thud created a dense Earth, and the splash created the lower density moon. 

To better understand exactly what happened, we really want to explore all the different kinds of minerals the Moon has, and because asteroids have hit the moon many times, we know some of the minerals from its interior have been tossed onto its surface. Ideally, we want to get our hands on these free samples from deep in the Moon, and we want the freshest samples we can get. This means, sending rovers or humans to the Schrödinger Basin, the youngest basin on the Moon. 

In preparation for future exploration, Ellen Czaplinski and a team of students poured over lunar images of the lunar south pole’s Aiken Crater and the Schrödinger Basin to map the minerals we most want to sample and understand. According to Czaplinski: When the Schrödinger basin was formed, some of these lithologies (the general physical characteristics of the rocks) may have been uplifted from very deep below the lunar surface. … Many of these rock types are exposed at the surface in multi-kilometer long exposures of rock outcrops in Schrödinger’s ‘peak ring,’ an inner ring of uplifted rocks that formed with the basin.

Along with mapping the minerals, the team also mapped out three potential paths for future rovers, or maybe even humans, to explore. Now with these maps in hand, we just need to land more robotic or biologic explorers on the Moon.

More Information

Great chance to spot a very young moon April 12 (EarthSky)

Waxing Crescent Moon (timeanddate)

University of Arkansas press release

“Human-assisted Sample Return Mission at the Schrödinger Basin, Lunar Far Side, Using a New Geologic Map and Rover Traverses,” E. C. Czaplinski et al., 2021 March 12, The Planetary Science Journal