The trouble with finding out we’re going to have an extra moon hanging around is that the reality isn’t quite as exciting as the headline. The moon we’ve got is pretty spectacular and it’s always been easy to dream of having several. Maybe they’d be different colors and sizes, people could have favorites, and without a doubt they’d do an utterly predictable dance with each other that I will never be able to comprehend, but will enjoy. Bring ‘em on, I say.

So we’re due for an extra moon September 29th. They are calling this one a mini-moon, but that’s still pretty fancy for a pitted potato about the size of my house. We won’t be able to see it. It’s a disappointment. The idea is it would orbit Earth for 57 days, and then peel off to orbit the sun again, like some space tourist. Just going to have a gander at our open-air markets and an ancient church or two, and then right back to grab a Cinnabon and a souvenir T-shirt on the way back home.

Which didn’t make sense to me. If some potato was going to orbit the Earth, seems to me it would just keep orbiting, and eventually grow closer and closer and flame out into tater tots over our oceans. If the Earth sucks hard enough to grab an asteroid it shouldn’t spit it right back out again.

Turns out I’m correct about that. It’s not going to orbit properly in a nice tidy circle but sort of bloop around the Earth in a horseshoe trajectory before having second gravitational thoughts. There are a number of these travelers the experts have their eyes on, just in case they were planning to blow us to bits, and they know when they’re going to show up and when they’re going to leave. This one, for instance, is slated to come back in 2055. They say that, but hey. Asteroids these days! They’re all Be there with bells on! on the RSVP but when it comes down to it they might not show up at all if something more interesting drifts by.

This sucker travels in the Arjuna Asteroid pack, which is unusual in not being named after anything Roman. These are near-Earth objects with similar orbits around the sun, such as taking about an earthly year for the trip, and having low inclination. I looked up “inclination” for you but my whole brain seized up, as it always does when dealing in spatial visualization. Before I knew it, we were deep into something called the Argument of Periapsis and that’s just not something I want to get into, in these contentious times.

Not only that, but I learned the Sun has an equator, which I was not aware of. I would have thought it had burned up by now. My father minored in astronomy and labored rather hard to jam some of this stuff into my feeble brain, but, being overstuffed with metaphor, it had low inclination. He’d be happy to explain it to you, but he’s 116 years old and doesn’t get out much anymore.

Anyway, I hope you all enjoy the invisible company of our new space turd while you can, and try not to be upset you can’t see it. You wouldn’t believe the number of cool things we can’t see.