We see patterns in so many things. They're useful in stargazing because they help us find our way around the sky. Even if all you know are the Big Dipper and Orion's Belt, you can use them to navigate to other stars and constellations. In turn, those new stars and shapes can further extend your celestial reach.
Humor has found its way into the sky as well. Witness the Cheeseburger Nebula (planetary nebula NGC 7026 in Cygnus), Fish on a Platter (dark nebula B144, also in Cygnus) and the Running Chicken Nebula (IC 2944 in Centaurus). Names and patterns — and especially humor! — aren't just good for navigation. They help us remember things. Make them stick.
In this spirit of fun I share the Mickey Mouse craters on the moon. I don't know the origin of the name, but the trio is a good likeness of the cartoon character's face and big ears..
The craters Licetus and Cuvier form his ears, and Heraclitus the head. A fourth crater, Heraclitus D, resembles a fanciful mouth with an expression of surprise. The trio is best visible 7-8 days after new moon and again 5-6 days past full moon. Even a small telescope will show you Mickey. He's located in the moon's rugged southern highlands, a heavily-cratered region comprised of the original lunar crust that formed some 4.3 billion years ago. The highlands, rife with craters from meteorite and asteroid impacts from that era, are testament to the solar system's violent early history.
Both Licetus and Cuvier are 47 miles (75 km) in diameter and 2.4 miles (3.8 km) deep. Their worn-down rims tell us they're ancient, having formed in separate impacts sometime between 3.9 and 4.6 billion years ago. Yes, there is erosion on the moon! The steady bombardment of micrometeorites and the solar wind slowly grind and smooth the sharp edges off lunar features over the course of millions of years.
Heraclitus, named for the 6th-century B.C. Greek philosopher, is a more complex crater 56 miles (90 km) in diameter with an odd, elongated shape. If you look closely you can can see that Cuvier abuts Heraclitus while Licetus actually overlaps and cuts into its northern edge. That tells us that Heraclitus formed first, followed some time later by Licetus. If you increase the magnification of your telescope a little, you'll see that a ridge runs along Heraclitus's shallow floor.
What makes the Mickey face work is that all three craters overlap to some degree, so they fit together to create a striking pattern. You'll be able to see the face tonight (Sept. 14) and tomorrow night before the glare and lack of shading makes the triplet difficult to discern. If clouds interfere. try again on the nights of Sept. 25-26 during the waning moon. Or you can wait until October 10-12 when the waxing, evening moon carries them back into view again.
You'll need a small scope for this, around 3-inches (80mm) should do. Use a magnification around 60-100x and look for Mickey a short distance up (north) from the bottom (south end) of the moon. Two much larger craters — Stofler (78 miles, 126 km) and Maurolycus (71 miles, 114 km) — lie a short distance above or north of the face.
As in the sky, once you find an anchor site on the moon, you can work your way from there to other lunar features and come to know the moon better. To further your quest, download the Moon Globe app (free) for iPhone and Lunar Map HD for Android. Both include nicely detailed maps of the lunar landscape.
"Astro" Bob King is a freelance writer for the Duluth News Tribune. Read more of his work at duluthnewstribune.com/astrobob.