OUMUAMUA UPDATE: IT’S A COMET, NO, AN ASTEROID, NO, A COMET, NO, ...July 2, 2018
A few days ago I mentioned the comet, or rather, asteroid, Oumuamua in one of my blogs about space matters. (See NASA’S NEW ASTEROID DEFENSE PLAN). Why the hesitation over what the strange object is? Well, in my blog, I referred to it as a comet. Almost as soon as the blog was posted, I began to get articles from well-intentioned readers, stating that it was - no, not a comet - but an asteroid. I was just about to post a "Tidbit" correcting the error, when more articles began to arrive: no, it was not an asteroid, it was a comet all along.
Well, so much for posting a note about the error.
Then, amid the growing pile of emails in my inbox folder about Oumuamua, I found this, shared by Mr. J.T, which "clarified" the issue:
So, that's why I was confused; I was confused, because scientists themselves are confused:
The bizarre interstellar visitor that whizzed through our Solar System late last year stunned scientists the world over. The object, named Oumuamua snuck up out of nowhere, cruising around the Sun and then slingshotting back out into space before most astronomers even knew what to make of it. Its strange shape and odd coloring were so strange that some researchers thought it might have been an alien probe checking us out.
Once that was put to rest, one of the more humorous twists to the story was the repeated flip-flopping of scientists who couldn’t decide whether it was a comet or an asteroid. It was initially thought to be a comet, but its lack of an iconic tail suggested otherwise. So, it was an asteroid, at least for a little while, but subsequent rounds of research suggested it was a comet again… then an asteroid, again. Now, yet another study has been published in Nature and, well, it’s definitely a comet. Again.
The new paper, which was led by an astronomer with the European Space Agency (ESA), takes a close look at the strange visitor as it speeds away from our Solar System. The data reveals that the object is speeding up as it exits our neighborhood, which shouldn’t be possible if it were just a rocky asteroid being flung by gravity.
Instead, the researchers say, the object being a comet would explain its acceleration. The idea being that gasses heated during Oumuamua’s close brush with our Sun are actually pushing it faster and faster, matching what we know about comets.
So, because it lacked the typical tail of comets jetting into the solar system, it was a mere asteroid. But because it has gasses jetting out of it as if flies away from the Sun, it's a comet again.
I get it! I understand! Yea, sure! It's a comet! I'm so relieved!
Except, wait a minute... shouldn't those same gasses have been jetting out of the object as it approached the Sun and heated up? And shouldn't the trees grow taller too, in a natural selection response to the giraffes growing longer necks in natural selection to reach the leaves? Wait a minute, isn't that kind of a circular argument? (Remember that one?)
Well, yes, the lack of a comet tail coming into the solar system, meant it was an asteroid. But the evidence of out-gassing on the way out of the solar system means it's a comet, notwithstanding that the gas was apparently not turned on during the inbound flight of the comet...er... asteroid. Maybe it's an astercometoid.
Now, as you can tell, I'm having a bit of fun with this one, because the article itself mentions the problem that is posed, and where most scientists "don't want to go." In fact, it even mentions the fact that some scientists were trying to communicate with the object, given its other bizarre behavior. They were willing to entertain the "impossible," that it was an interstellar probe of some sort:
Ahhh! So there we go... they tried listening for signals, but there was nothing. No signals, no out-gassing, just a long cylindrical rocky object tumbling end over end... until it seems to have started out-gassing again... one wonders which of the ends that out-gassing is coming out of, perhaps both?(That would be very un-cometlike, and for that matter, very un-asteroidish. In fact, it's very un-comet-like and un-asteroidish to have no tail coming in, but one going out.).
In fact, that tumbling action, for such a shaped object, might indicate some prior impact that set it tumbling...
So, yea, I'll say it...
...maybe someone turned on the engines again...
(Oh, just in case, they've got a theory for that unusual out-gassing too, and you'll love it too: its dust is simply "bigger":
... See you on the flip side...