This is an update in my continuing coverage of the increasingly mysterious object 1I/2017
U1, or Oumuamua, the first observed interstellar object to pass through our solar system.
For the backstory, check out my other videos on this channel on the subject, links in the
description below and in the end screen.
This story has gone into very different territory since my last update as more information has
come out regarding the object.
Very creepy and interesting territory in fact, it’s like the early days of KIC 8462852
all over again.
There is a possibility now being seriously discussed, albeit a very small possibility,
that Oumuamua could be artificial in nature.
I stress small, this is overwhelmingly likely to be an asteroid, but the chances are not
zero prompting Breakthrough Listen to point the Green Bank radio telescope towards the
object just in case it’s emitting something.
The reason for this attention is the more we look at Oumuamua, the weirder it seems
to get.
The first thing that we know is that Oumuamua is very likely to be an interstellar traveler.
It came into the solar system fast and it’s leaving it fast and it seems clear at this
point that the object is not gravitationally bound to the sun and indeed originated in
another star system.
We’ve suspected for decades that such things existed.
Solar systems eject material routinely and we expected we would some day detect something
passing through.
In fact, it’s probably something that happens very commonly and now that we can detect these
objects, we’ll hear of such things regularly from here on out.
Trouble is, we thought we knew what such a thing would look like once we saw it.
This was not the case.
We thought the most likely thing we would see is a passing comet.
It’s more likely that cold comets from an outer solar system would get ejected more
often than things like planets and asteroids from inner solar systems, though that’s
also easily possible.
But several studies have shown that Oumuamua is not a comet and therefore would have to
be an asteroid.
Those are likely going to be a bit scarcer once we really start discovering and studying
interstellar visitors, but not impossible by any means.
Trouble is, we’ve seen a lot of asteroids but we’ve never seen an asteroid like this,
it is unlike any known object in our solar system.
The object seems bizarrely elongated, at least as we understand it right now.
It’s essentially thought to be rod shaped, possibly 10 to 1 longer than it is wide, and
there is some thinking that if you wanted to create an interstellar spacecraft this
would be the best shape in order to minimize erosion from dust in the interstellar medium.
More, nature doesn’t really like to create these kinds of shapes, instead things tend
to erode and round out and asteroids in general tend to be more like conglomerated loose rock
piles than completely solid objects.
Neither seems to apply to this object, but I caution, new data comes out about this object
frequently, and we don’t yet have a complete picture here.
As it stands, Oumuamua has to be pretty solid.
It’s thought to be tumbling wildly, basically out of control.
That’s not good for a spacecraft unless you’re looking to produce artificial gravity,
but this spin doesn’t appear to be going fast enough to produce much in the way of
that.
So, barring that, propulsion system failure would rise to the top as the reason.
And, natural objects tumbling is weird in itself, things tumbling in space tend to settle
down to rotate more simply over time.
Something has to start it tumbling, getting ejected from a solar system might do that,
but while tumbling can last for a long time, especially if the object is rigid, this object
appears to have been travelling through deep space for a very long time.
Perhaps something sent it tumbling after it left its system of origin.
But there’s also nothing that suggests it is, or ever was, under any kind of control.
The sun’s gravity altered its path in a way that appears fully consistent with nature.
But this tumbling would mean it has a pretty solid composition unlike most asteroids.
In other words a solid, or nearly solid, rock or metal composition.
Again, this is unusual, but not impossible, we know from meteorites that both solid rock
and metal are abundant in space and there is an entire class of very sturdy meteorites
that are made up of metallic nickel iron so pure you can polish them like steel.
So this doesn’t immediately mean too much, but asteroids are usually not like this.
And it has to be said that things can also artificially be made to be sturdy.
On the asteroid front, the closest thing we have to Oumuamua in the solar system is the
asteroid Kleopatra which is barbell shaped due to it being made up of two objects touching,
that could be the case for Oumuamua as well.
The problem is that Kleopatra is not spinning wildly enough to fly apart, it’s very fragile
and a typically loose conglomeration of material like most asteroids.
Oumuamua is spinning to fast to hold together like a normal asteroid, ending all similarity.
So the bottom line here is that while it’s overwhelmingly likely that Oumuamua is an
unusually solid asteroid, it’s one that’s creating more questions than answers at the
moment.
But there are plenty of other things that point to this object being fully natural,
such as its color, which is consistent with an asteroid that’s travelled through deep
space for a long period of time.
There are also no other measurements that suggest that it’s anything but natural.
But there is a tiny chance that it might be more, so it’s prudent for Breakthrough Listen
to take a look just in case while we have the time.
Oumuamua is well on its way out of the solar system.
But I wouldn’t expect much in the way of results, if it’s an asteroid, it will be
silent.
If it’s a derelict spacecraft spinning out of control, whatever happened probably took
down the transmitters, though maybe not.
In short, while I think this is an asteroid, I’m really enjoying that the first interstellar
object we’ve identified has turned out to be so mysterious and incredibly weird.
So in that spirit, I will leave you with one final oddity about this visitor.
When it passed through the inner solar system, it came in from above and swung past the sun,
which then gravitationally perturbed Oumuamua such that passed only about 60 times the distance
to the moon from us.
That it passed so closely to an inhabited planet is an eyebrow raiser for sure, though
again it’s likely just due to chance, and if it wanted to study earth it probably would
have come even closer.
But maybe it’s not that simple.
If studying earth itself was not the objective, rather just seeing if there was life or a
civilization here, Oumuamua passed well close enough to answer that question.
And say it is a damaged spacecraft, it may have intended to come closer but couldn’t,
or didn’t in order to ensure that it wouldn’t hit earth.
I would find that encouraging, it would mean the alien’s stuff breaks down too and they
conscientiously made a point of not smacking into us with their derelict.
Thanks for listening!
I am futurist and science fiction author John Michael Godier currently shamelessly plugging
a book!
I know, I’m always doing that but this time it’s someone else’s!
To fire your imagination about the possibilities of Oumuamua, read Arthur C. Clarke’s very
relevant book “Rendezvous with Rama”, it’s one of my favorites and a fun read
under the circumstances.
It can be found at your favorite online book retailer and be sure to subscribe to my channel
for regular, in-depth explorations into the interesting, weird and unknown aspects of
this amazing universe in which we live.