This entourage of weirdos hangs out in Earth's cosmic neighborhood
Mary Beth Griggs
at 10:57 AM Oct 23 2017
This entourage of weirdos hangs out in Earth's cosmic neighborhood
I've been there
NASA
Space // 

Earth is a planet of habit. It rigorously adheres to a whirlwind of a daily schedule, spinning through its tasks (mostly: spinning.) In terms of long-term plans, it has those down too. It orbits the Sun every 365 days 5 hours 48 minutes 46 seconds, thank-you-very-much.

That's not to say it doesn't change things up periodically. It goes through phases, sometimes tilting its northern hemisphere towards the Sun, and sometimes the southern hemisphere. It's good to mix things up.

During its orbit, Earth sticks to a well-worn path around the Sun, minding its own sweep of the solar system just like it has for 4.6 billion years. It doesn't get out beyond that, but Earth isn't lonely. It has plenty of visitors. One group is stopping by this weekend to party with the planet.

Like many of the other meteor shower crews, the Orionids stop by once a year, dropping in like clockwork with a big, enthusiastic show. These are the friend groups that Earth catches up with every time they're in the same place, delivering consumable hostess gifts of dust and debris into the atmosphere, decorating the night sky with a light show in the process.

Of course, it's not like meteor showers spring out of the sky fully formed. Just like Earth, they've got a history. In this case, a family history. Earth knows their parents too, though the comets don't drop by nearly as often. The last time Earth saw the Orionid's mom Halley was in 1986, and it's not going to see her again until 2061. It takes a long time to travel into the bustling metropolis of the central solar system from where she lives, way out in outer reaches of the system.

It's cool though; Halley's other kids, the Eta Aquariids, will stop by in May. Halley's trips to the inner solar system always give the Aquariids and Orionids more material to work with, even if that material does come from Halley herself, melted away by the heat of the Sun. Comets are like that. Halley stops by more often than the other comets, but it's clear that the visits really wear her out.

Earth has plenty of other nearby neighbors. But luckily, they keep to themselves. These Near Earth Objects have a passing acquaintance with the planet—fellow commuters that know the other one is there, but who don't end up making so much as eye contact. At least, that's the hope. Researchers have identified about 16,885 NEO's so far, and would really prefer that they each stayed in their own lanes.

Earth is still finding the remains from the last time a really big NEO got too close. Dinosaur bones are so hard to get out of a nice sediment. Since then, Earth's mostly avoided NEOs at parties, though some dustups between these frenemys do occur every once in a while.

And Earth does have to deal with copycats every once in a while. For about 100 years, the little asteroid 2016 HO3 has been following Earth, dancing around the planet while it goes around the Sun—but not actually orbiting, even though it's circling around our planet at a constant rate. This week, scientists confirmed that HO3 really is just an asteroid orbiting the Sun who happens to circle the Earth in a moon-like fashion, and not space junk.

Speaking of space junk, the Earth has that in abundance. Earth's humans keep promising to clean it up, but don't hold your breath. Earth keeps pulling some of that space junk down into the atmosphere, but then, instead of being grateful, they're all worried that a space station will smash into them. Kids, amiright?

Oh, and how could we forget the Moon. This giant, solid hunk of rock hasn't left the Earth's side since they bumped into each other around 4.5 billion years ago. Since then, they've been through everything together. The Moon takes care of watering the Earth's coasts twice a day, moving around the Earth's oceans, and Earth's gravity keeps them together, though it does seem like they've been growing apart lately.

As for other relatives, Earth keeps in touch with a few on a more long-distance basis. Look, just because they all formed at the same time, that doesn't mean that Earth is that close to Mars or Venus. They've all chosen to go different ways, ok? Mercury is busy sucking up to the Sun, Venus is hot-tempered all the time, and Mars and Earth...well, they used to be way more alike than they are now. And don't even start on Jupiter, Saturn, Uranus and Neptune. They've all gotten so full of themselves out there, it's like they're too big for Earth anymore.

But that's fine by Earth. It's going to keep on doing its thing around the Sun, enjoying its visitors and hoping none of them outstay their welcome.

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