5 Facts About That Enigmatic Object That Invaded Our Solar System
A couple years ago, a big hunk of something flew into our solar system. It took a bit longer for the world to really stand up and pay attention to it, and we're still keeping an eye on it, even though it's now billions of miles away now. So, what's the deal with this thing? Here's a quick primer for you, starting with ...
First, The Most Important Part: What's With That Name?
Just kidding, the name isn't the most important part, but let us set this thing up for you.
In October 2017, astronomers were looking up at the sky, which is their favorite thing to do. They thought they spotted a comet, so they named it, using the standard comet designation protocol. Then they looked closer, saw no hint of a tail, and figured it had to be an asteroid, which meant they instead needed the asteroid designation protocol. But as they got out their notepads and tried to trace its path, they realized it had to have come from outside the solar system. It was the first ever identified interstellar object, which was very exciting, because it meant they had to create a NEW designation protocol.
From that point on, interstellar objects would receive names staring with the letter "I," and since this was the first, it would be I1. Which is an awful name. An unreadable name, even, depending on what font you use. So they also came up with a cooler name: 'Oumuamua. 'Oumuamua (try sounding it out, it's fun) came from a Hawaiian word for "scout," as though this is a messenger sent to us from a different galaxy or from billions of years in the past.
Zoom in on the name, so you can see that little curly bit in front, and something may look strange to you:
"Hey, that's not how an apostrophe is supposed to work," pedants among you might note. "Apostrophes are supposed to curl the other way, to look like a 9 instead of a 6." Right, but that mark isn't an apostrophe. That's an 'okina, a Hawaiian punctuation mark that tells you how to say the word. It's pronounced OUH-mua-mua, rather than oh-MOO-ah-MOO-ah.
We wanted to tell you this upfront because 1) the interstellar object 'Oumuamua, like the 'okina in its name, curls in a weird way, and 2) we thought it would be nice to zoom in on the name for you, as there's no way to zoom in on the object itself. You see ...
We Don't Actually Know What This Thing Looks Like
At the top of the page, and copied again right below these words for your convenience, is an artist's impression of 'Oumuamua:
Scientists, and the media, unanimously refer to this as "cigar-shaped," which is the term they use when they want you to think about dongs but are too afraid to just come out and say "dong."
Seriously, that has to be what they're doing, right? Because otherwise, "cigar" is a dumb point of reference. How many of us smoke cigars? When was the last time you even saw a cigar? They could call that shape "finger-like," or "shaped like a log," or just plain "oblong" and we'd get it, but no, they all refer to it as "cigar-shaped" to really drive home that they mean phallic. In particular, scientists note the similarity in shape to the interstellar object from Arthur C. Clarke's Rendezvous With Rama, and it makes sense that that object in that book would be cylindrical, considering how much Arthur C. Clarke spacecraft are made of genitals.
So, 'Oumuamua is called cigar-shaped. But we don't know if it really is. 'Oumuamua is roughly the size of a city block, which is huge for a cigar but tiny on a celestial scale, so there's no way to focus our telescopes on it and examine it. When we said earlier that scientists observed 'Oumuamua, we meant that scientists picked up the radiation that it reflects as it rotates, and they used that to infer its shape. They might have got it wrong. It might instead be a disc, like in this other NASA illustration:
All this is to say -- and this will become important in a minute -- there's a whole lot of very basic info about 'Oumuamua we don't know. But we have been able to monitor its movement, and that's what's stumped so many scientists.
'Oumuamua Is Moving Very Weirdly
As those astronomers were tracking 'Oumuamua (during the few breaks allowed to them by their droves of oversexed groupies), they realized their interstellar visitor could not have come from the fairly close star system Vega just 600,000 years away, nor could it have come from any of the first several other close alternatives they checked out. The paths just didn't line up. Instead, 'Oumuamua might have spent billions upon billions of years traversing the cosmos before it landed in our solar system.
But that's not the weird part about its motion. The weird part: 'Oumuamua was accelerating. Not just accelerating due to the Sun's gravity, as expected, but also accelerating due to ... something else.
Maybe stuff on it was evaporating and propelling it forward? Probably not, because we know what that looks like, and we didn't see any signs of that, which was why we decided 'Oumuamua's not a comet. Maybe dark matter is involved somehow? Impossible to say, as all spells involving dark matter have been forbidden by the council of wizards.
Or could solar radiation, in addition to the Sun's gravity, be moving 'Oumuamua? For that to happen, 'Oumuamua would need some kind of large, thin surface capable of harnessing radiation. We can't say for certain that it doesn't have one of these because, again, we haven't actually been able to get a look at 'Oumuamua. But this surface -- a solar sail -- would be a complex piece of engineering, not something that a broken piece of rock acquires naturally. Engineering implies the existence of engineers. Engineers from outside our solar system.
So, Is This An Alien Spaceship?
C'mon. Couldn't It Be Aliens?
Okay, we can't rule out that aliens made it. But if you've heard the theory that 'Oumuamua is an alien spaceship -- and if you heard of 'Oumuamua before today, you probably heard this theory -- you should know that despite all the coverage it got, this idea comes from just one dude. Well, two dudes, counting his paper's co-author, who doesn't seem to chase the spotlight as much.
Now, as lone dudes go, Avi Loeb is more reputable than most. He's a Harvard astrophysicist, and the longtime chair of their astronomy department. If you expect us to go point by point and refute the science of his reasoning, uh, no, we'd have to get ourselves a PhD or two before we're equipped for that. But what we can do is point out that just about every other scientist disagrees with him, to the point of that they say entertaining his theory is a mockery of science itself.
Yes, there is certainly alien life among the squinzillions of galaxies out there, and even intelligent alien life seems all but certain. But calling this one unidentified tumbling object an alien machine is what scientists call an extraordinary claim that needs extraordinary evidence. Loeb doesn't have evidence, just the absence of a good alternative explanation ... and he claims he doesn't need evidence. "It is not obvious to me why extraordinary claims require extraordinary evidence," he says. "Extraordinary conservatism keeps us extraordinarily ignorant."
We can't explain why a rock is moving a certain way and therefore some intelligence must have designed it that way ... this sounds, to Loeb's critics, a bit like the argument for believing in God, which is beyond the scope of astrophysics. In fact, this whole thing is almost an exact real-life version of Russell's teapot, a parody of bad arguments. You can't prove a teapot isn't orbiting the Sun somewhere between Earth in Mars, joked philosopher Bertrand Russell. Similarly, we can't prove 'Oumuamua out there in space has no solar sail. But it still probably does not.
Other scientists representing five nations got together and in the end explained 'Oumuamua's weirdness to their satisfaction. Maybe the Sun heated the volatile compounds unevenly, which creates propulsion but prevents us from noticing what's happening. There's also a new theory now saying 'Oumuamua could be a shard from a distant planet that exploded. So, even if it's no Millennium Falcon, it could still be a green remnant of a shattered Krypton, which is something.
Let's Go And Find Out For Sure
There's a reason we're still talking about 'Oumuamua today, and that reason is Project Lyra. This group of scientists is considering sending an interstellar ship to catch up with 'Oumuamua, even though it's already billions of miles away and going 500 million miles farther every year.
Are they nuts? No, no they are not. We absolutely do want to catch up with interstellar objects eventually, and 'Oumuamua's a good candidate because at least we know where to find it. The other plan for reaching an object like that has been approved by the European Space Agency and involves sending a vessel into space by the end of the decade and then just chilling for a while till we figure out where to direct it. Compared to that, Project Lyra seems downright reasonable.
They want to launch a spacecraft in 2030. You have to time these missions carefully according to when planets align; astronomy and astrology are similar in this way. The ship will then have to travel 20 billion miles over the course of the next 20 years, with hopes of rendezvousing with 'Oumuamua in 2049, when it's five times farther from the Sun than Pluto is. Current space technology wouldn't allow us to manage something like that, but the scientists have suggested new propulsion methods, including lasers, nuclear bombs, and of course solar sails.
Before they launch, Project Lyra also needs funds, and personnel, and manufacturing facilities, and lots more. The group behind it (the "Initiative for Interstellar Studies"), they're just some scientists writing a proposal, not a space agency. But we're absolutely rooting for them to come up with a plan that makes sense and to put it in the hands of those who can make it happen. And if they do discover that 'Oumuamua is a functioning spacecraft, we will admit we were wrong, and then we'll commandeer the vessel and fly it back to where it came from. We have some ideas about what we can do with the aliens there. The specifics depend on whether they have cigar shapes.