Space fans, get your telescopes ready.
NASA did not identify the craters in its tweets (opens in new tab) or during live coverage yesterday (Dec. 5), but space journalist Philippe Henarejos suggests the big one visible near the video's center is Kepler, a 19-mile (31-kilometer) divot in the Ocean of Storms, which is approximately near the landing zone of Apollo 12.
Barely visible near the horizon is a behemoth: Gassendi, roughly 69 miles (111 km) in diameter. "Both are visible from the Earth through a small telescope," Henarejos said in a tweet (opens in new tab). Gassendi was the alternate landing site for Apollo 17, which touched down in the Taurus-Littrow region almost exactly 50 years ago on Dec. 19, 1972.
Kepler is one of the top eight craters that Space.com says should be visible in your own telescope, in our moon observing guide. Finding this crater will be a cosmic treat, as Kepler is a complex crater that includes a flat floor, as well as terrain like peaks and terraces, according to NASA.
"Complex craters occur above a certain diameter crater, the cutoff diameter is dependent on gravity, so it varies from planet to planet (or moon to moon)," NASA officials wrote (opens in new tab) of Kepler. Simpler lunar craters, which look like a bowl, tend to be less than 6 miles (10 km) in size and complex craters are somewhat larger.
As for Gassendi, Apollo 17 was tentatively targeted for a region south of the central peaks rising in the crater, with the hopes of finding ancient rocks in the highlands, according to NASA. These rocks may have helped to date not only the impact that caused Gassendi, but for the nearby Humorum basin.
"However, engineering constraints kept Gassendi from becoming an Apollo landing site because it was uncertain if the terrain within Gassendi was too rough and dangerous for astronauts to successfully approach the central peak and obtain a sample," NASA officials wrote in another web page (opens in new tab).
Future Artemis program missions will target yet another region of the moon, near the lunar south pole. The rocks in that region should be different than the basalts that Apollo astronauts largely collected, NASA deputy curator Juliane Gross said in comments during the NASA Television flyby coverage Monday.
Future landing crews, starting with Artemis 3, may find rocks that generated from the huge crash that caused the South Pole-Aitken basin, Gross said. Such a find would show "our own history and how the moon formed and evolved over time, better than we can with Apollo," Gross added.
Elizabeth Howell is the co-author of "Why Am I Taller (opens in new tab)?" (ECW Press, 2022; with Canadian astronaut Dave Williams), a book about space medicine. Follow her on Twitter @howellspace (opens in new tab). Follow us on Twitter @Spacedotcom (opens in new tab) or Facebook (opens in new tab).