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Could 'Oumuamua Be A Fluffy Radiation-Driven Icy Fractal From Another Star System? (syfy.com)
"Oumuamua, the first object ever seen passing through our solar system from interstellar space, was thought to be emitting gas like a comet to explain its weird motion," reports Syfy Wire, "but a new idea is that the comet is just very, very porous."
Astronomer Phil Plait writes: It was hard to tell what it was; it was too small, faint, and far away to get good observations, and worse, it was only seen on its way out, so it was farther from us literally every day. Then another very weird thing happened: More observations allowed a better determination of its trajectory, and it was found that it wasn't slowing down fast enough. As it moves away, the Sun's gravity pulls on it, slowing it down...but it wasn't slowing down enough. Some force was acting on it, accelerating it very slightly... A new paper has come out that might have a solution, and it's really clever. Maybe 'Oumuamua's not flat. Maybe it's fluffy... [And thus moved by the force of sunlight giving it a tiny push]
When stars are very young, they have a huge disk of material swirling around them; it's from this material that planets form. Out far from the star, where temperatures in the disk are cold, teeny tiny grains of dust and water ice can stick together in funny shapes, creating fractals... Materials made in a fractal pattern can be very porous, and in fact out in that protoplanetary disk around a young star, physical models show that objects can grow fractally until they're as big as 'Oumuamua, and have those extremely low densities needed to account for its weird behavior. So 'Oumuamua doesn't have to be a spaceship. It just has to be a snowflake! A three-dimensionally constructed phenomenally porous low-density snowflake... [T]he new paper suggests it came from a nearby star, and one that's relatively young (less than 100 million years). It formed out in the disk, and got ejected somehow, likely from a planet forming nearby giving it a boost from its gravity.
"I certainly hope we find more beasties like this one," Plait writes. "They can tell us so much about how planets form in other star systems, which is pretty hard to figure out from dozens or hundreds of light years away.
"It's a lot easier when they obligingly send bits of their building materials to us."
Astronomer Phil Plait writes: It was hard to tell what it was; it was too small, faint, and far away to get good observations, and worse, it was only seen on its way out, so it was farther from us literally every day. Then another very weird thing happened: More observations allowed a better determination of its trajectory, and it was found that it wasn't slowing down fast enough. As it moves away, the Sun's gravity pulls on it, slowing it down...but it wasn't slowing down enough. Some force was acting on it, accelerating it very slightly... A new paper has come out that might have a solution, and it's really clever. Maybe 'Oumuamua's not flat. Maybe it's fluffy... [And thus moved by the force of sunlight giving it a tiny push]
When stars are very young, they have a huge disk of material swirling around them; it's from this material that planets form. Out far from the star, where temperatures in the disk are cold, teeny tiny grains of dust and water ice can stick together in funny shapes, creating fractals... Materials made in a fractal pattern can be very porous, and in fact out in that protoplanetary disk around a young star, physical models show that objects can grow fractally until they're as big as 'Oumuamua, and have those extremely low densities needed to account for its weird behavior. So 'Oumuamua doesn't have to be a spaceship. It just has to be a snowflake! A three-dimensionally constructed phenomenally porous low-density snowflake... [T]he new paper suggests it came from a nearby star, and one that's relatively young (less than 100 million years). It formed out in the disk, and got ejected somehow, likely from a planet forming nearby giving it a boost from its gravity.
"I certainly hope we find more beasties like this one," Plait writes. "They can tell us so much about how planets form in other star systems, which is pretty hard to figure out from dozens or hundreds of light years away.
"It's a lot easier when they obligingly send bits of their building materials to us."
I like this kind of articles, they expand my knowledge of things astronomical.
...gis sdrawkcab (usually not responding to ACs; don't bother posting as AC)
It could be but then similar events have been observed here on Earth.
Just go in the Santa Clare County between San Jose and Palo Alto and you can freely observe an object similar to Oumuamua which is emitting gas at a higher rate than a comet. That would explain its weird motion.
"Oumuamua doesn't have to be a spaceship"
Um, if there is one thing it is not is a spaceship. Can we get any dumber? Where would a spaceship possibly come from? There is no system close enough to Earth. It would take hundreds of thousands of years for a spaceship to get here from anywhere.
Something approximating a Sierpinski Pyramid (which has zero density)?
https://upload.wikimedia.org/w...
and before there were spell checkers to fubar a word that was never a word before.
I was shown pictures that proved that it was flat, by looking at it sideways, and seeing a narrower shape. By apparently proper science news.
And now TFS casually talks about it not being flat.
Is this some kind of reverse flat earther joke? Did they branch off into a round oumuamuaers?
Am I misremembering?
A kingdom for a link to that article with those pictures!
There's a bowling ball on a trampoline. I roll a tennis ball past it. That's when this magical mystery force called gravity starts eminating from the bowling ball. The magical mystery force pulls on the tennis ball, slowing it down. The magical mystery force also alters the tennis ball's trajectory, making it curve around the bowling ball.
Read "Debunking 9/11 Debunking" by David Ray Griffin for more interesting science.
Can' be, because my brain can't handle it! Waaah!
What was that about trying the most obvious simple answer first, and only moving on to more convoluted hypotheses if you can fully rule it out?
I'm NOT sayig it is a spaceship by the way. I'm sayig we should double- and hexadeci-check before we move on to dragged-in-by-the-hair hypotheses like "is must be *insanely* fluffy" or "it must be $someOtherDesperateCrazyBlackeyerTheory".
As soon as your mind becomes irrational and rules out things based on what you want it to be, you're disqualified from scientific discussion.
I'll be quite happy with it *not* being a space ship, if that is indeed the case.
Would you be quite happy with it *being* one, if that is indeed the case?
Oh Mamy Blue... Obviously this is just a side mirror that fell off the Chariot of the God when it left the dealer's lot. Otherwise, something like a Car Turd that dropped off in winter. The possibilities are endless.
for billions of years, some star probably exploded and destroyed the planets orbiting it sending debris hurtling though space possibly beyond the galaxy that it resided in, but more than likely it resided in this galaxy
Politics is Treachery, Religion is Brainwashing
It was the Crystalline Entity checking us out for the future
See, this is why publishing even highly speculative papers can be productive. I see this as a response to the paper that everyone keeps talking about in terms of 'omg aliens!', where really the person just layed out how much the object would have to weigh in order for its movement to be described like a light sail and then speculated about what types of objects, such as artificial ones, could have that kind of weight to volume ratio.
So now here we have another person taking that idea and proposing how something with those same characteristics could have a naturally occuring origin. This is what I love about watching scientists figure something out. You start with a mystery, someone proposes a mathematically consistent but kinda out there solution, others pick it apart, work with some bits while dropping others and propose a new solution. This is one of the major reasons publication is so important, so others can build off of ideas, even half baked ones.
You're thinking of Ultima Thule.
Think of the profits to be had from lassoing that "rock" and bringing it back to earth! We could close down the melamine mines forever! No one will ever have a yucky bathtub again!
If we could only figure out what the Dark Knight Satellite is. /sarc
Oumuy McOumuyface would have been more appropriate.
https://www.brighteon.com/5830377955001 yyy
For this reason, God sends them a powerful delusion(operation of wandering)(planet) so that they will believe the lie.
Sun researchers find strange eclipse reading
Mystery Red of the Great American Eclipse
It has blood on it!
ABCNews: Eclipse makes pendulum wander
that it's a (artificial) solar sail or that it accreted naturally with a density of roughly 1/100th that of air? My guess is that there's some mistake in the computation of its trajectory. (One scenario is that the image was actually of a 'string' of objects - following close in the same orbit but only occasionally visible.) An aerogel has a density of about 10% that of air, I see no plausible way to reduce hat by another factor of 10.
...wouldn't we have seen some out gassing if this thing were made of water when we first detected this? And isn't that precisely one of the mysteries with this thing, is that we didn't see any out gassing?
Mod me down with all of your hatred and your journey towards the dark side will be complete!
Oumauamua could be an outgassing comet-like body. Or, if it is a solar sail, and outgassing, in which case any acceleration we see must be explained by photonics pressure alone. This calculation give the very low densities given in the post.
In one astronomy post web group (which is hardly a scientific survey) the original argument that Oumauamua was a solar sail were accepted as "promoting the discussion", but there were demands that early papers for the scientific community replying on arXiv were not properly peer reviewed and so should be stricken from the record. This is weird: not only were the authors and arCiv doing a reasonable job against a set of unsubstantiated claims, you would also not expect a peer-reviewed article to come as quickly. So, in effect we are allowing people to post wacky propositions about alien spacecraft, but not allowing rational criticism from the body of experts whoo is most likely to have a useful contribution.
Astronomy is a long game. Have your little victories winning short-term arguments this way. The stars will be much where they were when you have long gone. And whoever was right will still be right. We can all wait.
So this thing has a constant acceleration? For how long has this thing been accelerating? How much longer can it accelerate? And why is it not going much faster than it is, given this thing came from outside our star system?
This must have a great amount of energy stored in it!
Oumuamua so fat, she's an icy fractal from another star system!
"Oumuamua"?
Why it is named in babbling of sub-Saharan Imbecilish?
... if a penguin tries to merge with it, we all know what happens next.
Put a fork in it because this web site is so done. Look at the responses to this interesting 'special snowflake' hypothesis to explain the only interstellar object we've ever seen. Sigh. This used to be a place where at least some highly intelligent people would post. Not anymore.
Quite an experience to live in fear, isn't it? That's what it is to be a slave.
It could be a wrecked spaceship. A hulk, dead for thousands or millions of years. And infested with hostile alien bugs. We could go there with squads of power suits to cleanse the hulk...