8 ms·

That Interstellar Asteroid Is Pretty Strange

143 points by okket 9y ago

wruza 9y ago
Say whatever you want, I know it is Silkie spaceship.
michaelwiliamd 9y ago
>It’s also our first direct look at an intact visitor (as opposed to dust specks) from another solar system. Would it not be possible to calculate the origin system based on speed, trajectory, star positions?
- rothbardrand 9y ago
  I don't think so... it slungshot around the sun, which implies that its in a very large sun oriented orbit. (eg: some random object passing bit for the first time would be likely only slightly disturbed by the suns gravity, not coming so close to it... the latter seems to imply it has been caught by the suns gravity.... or just happened to be aimed nearly directly at the sun.)
  - Taniwha 9y ago
    No, they distinctly say it is hyperbolic, not an ellipse, so not orbiting the sun
- dangerbird2 9y ago
  The problem is that the star positions change over time via galactic orbit. 'Oumuamua's trajectory appears to originate from Vega, but Vega would have been at a different position in relation to our solar system back when 'Oumuamua was at the same distance from the Sun as Vega.
  - deleted 9y ago
    [deleted]
- QAPereo 9y ago
  Not only is the system in question dynamic, as another pointed out, but also subject to perturbations. Worse, orbital mechanics with many bodies is chaotic, in the strict sense.
singularity2001 9y ago
tell me it's no the vanguard of a galactic police squad coming to arrest humans for universal misconduct
DanielleMolloy 9y ago
Here is the random astronomer on Reddit claiming that the community didn't rule out that it is an abandoned spaceship yet: https://amp.reddit.com/r/space/comments/7ealls/solar_systems_first_interstellar_visitor_with_its/ https://amp.reddit.com/r/space/comments/7ealls/solar_systems... "Astronomer here! I will never say this lightly, but we are, swear to God, actually discussing with some seriousness right now what are the odds that this was actually a spaceship. Which I 100% assure you has never happened before in my memory with seriousness."
- erikb 9y ago
  Why the hack do you assume it's abandoned? It can be full of lifeforms even and we are just not able to see them, talk to them, etc. Imo at this point any assumption is closing in too much. We don't have a definiton of "life" that for sure would include extraterrestrial lifeforms that are not actors with masks in star trek, right?
  - paulmd 9y ago
    Well, it's tumbling end-over-end which suggests that if it's a spaceship, it's no longer in control. The discussion around the possibility of it being a spaceship rests on the idea that long thin cigar-shaped objects are the most efficient way to travel in space because it minimizes your need for ablative protection from interstellar dust/etc. But if you're tumbling end-over-end you've thrown that advantage away, so presumably that's not a thing you would intentionally do. And if you are assuming that this spaceship has shields or whatever, then there is no reason they would be restricted to a cylindrical shape. It could be a discarded booster stage or fuel tank, of course. Maybe they were trying to drop it into the sun and missed. Or a a mass-driver shot (maybe they finally took care of that pesky Russell's Teapot for us...) The presumptive conclusion is of course that it's a natural phenomenon, but it sure is a weird object, and unless we can find a way to catch it (or any future objects) we will never know. Maybe a starshot probe could catch it?
    - deleted 9y ago
      [deleted]
Voloskaya 9y ago
> Occam’s Razor says it’s unlikely that the very first object we ever see from interstellar space just happens to be a spaceship. Well, isn't this kind of self fulling thing? Because we assume first that this is an interstellar asteroid, then the following statement is "proven": > Researchers had long theorized that space should be full of comets and asteroids ejected from other solar systems during their early days. Their models showed that planetary formation is a messy business, with many small objects kicked out as big proto-planets form. `Oumuamua is the first proof that they were right And at this point, yes, it appears very unlikely that the first interstellar object we meet would be artificial. But if we start by saying we don't know what it is, then the above theory is just speculation, and might be false (what if planeraty formation is a clean process?). If the theory above can be false, then it could make sense that the first interstellar object we encounter would be artificial, no? It seems to me that Occam's Razor doesn't tell us much in this instance.
- nuclx 9y ago
  What I thought. The absence of a priori knowledge prohibits the application of Occam's Razor in this case.
  - deleted 9y ago
    [deleted]
- hyperpallium 9y ago
  Unfortunately, Occam's Razor can say whatever you want by fiddling the apriori probabilities. Here, the probability you need is how likely that theory is to be true - just because it could be false doesn't mean it's 50-50. If all the models show planet formation is messy, it seems reasonable to estimate its probability as much greater than 0.5 (note that even if it's 0.9999, they still could be wrong).
  - Voloskaya 9y ago
    Totally agree. My point is just that I find it a bit weird/circular to use Oumuamua as the `first proof` for a theory that is subsequently used with Occam's Razor to demonstrate that Oumuamua is likely not something else.
hectorlorenzo 9y ago
These actually sound like last famous words.
joering2 9y ago
What's really shocking is the drawing from the article [1] This Astroid was Discovered when already passed by the Earth!! And was actually very close to it! While I am pretty certain Astronomers knew it won't hit us, the amount of time it took to discover it would be way too late for us to even hold hands and kiss our children goodbye! http://blogs.discovermagazine.com/outthere/files/2017/11/eso1737c.jpg http://blogs.discovermagazine.com/outthere/files/2017/11/eso...
- grkvlt 9y ago
  Well, if it had hit Earth, it would have happened without astronomers (or anyone else) knowing about it beforehand. As you point out, it was discovered after it had passed us, so there was no advance warning at all, however this is quite common with asteroids.
- valuearb 9y ago
  The earth gets hit by similarly sized asteroids every 30,000 to 100,000 years, albeit not quite at this velocity. Average impact velocity for asteroids from our system is 17 Km/sec, so about 2/3s the speed of this visitor. Either way, it's not even close to an extinction event. And "very close to it" is a misnomer. It came within 24 million kilometers of Earth, about 60 times farther away than the moon is.
sebow 9y ago
This guy is definitely obsessed with aliens
jfindley 9y ago
Are there yet any credible theories for why we see so few of these? AIUI, if we're correct about how planets form, there should be far more of these than we're seeing. Is it that we're probably wrong about how planets form, or there's something strange about our part of the galaxy, something else or do we just have no clue?
- dr_zoidberg 9y ago
  The general consensus amongst astronomers is that these objects are far too faint to be seen. As more sensitive instruments are developed/deployed, we should begin seeing more of them.
- Voloskaya 9y ago
  Estimate is that there might be about ~10 of these object passing through every year, so it's not a lot to start with. In addition asteroids are relatively small and hard to spot since they are inert. We managed to spot this one because we were lucky it came so close to earth.
splittingTimes 9y ago
So why exactly can we not get a better look at it as it is leaving? With all our earth- and spacebound telescopes [1] (some are sitting at Earth-Sun Lagrange points) I would imagine we could. Being too far away behind the sun seems an unlikely argument to me. === [1] https://en.wikipedia.org/wiki/List_of_space_telescopes https://en.wikipedia.org/wiki/List_of_space_telescopes
- grkvlt 9y ago
  The only working telescope at a Lagrange point is Gaia [0] at Earth-Sun L2, but it is an astrometry instrument, designed to measure the position and brightness of various stars, rather than generic deep-space imaging. The Herschel Space Observatory [1] is also at the Earth-Sun L2 point, and has a 3.5m IR telescope, but ran out of coolant in 2013 and is now defunct. Interestingly, these are both ESA missions, not NASA. 0. https://en.wikipedia.org/wiki/Gaia_(spacecraft) https://en.wikipedia.org/wiki/Gaia_(spacecraft) 1. https://en.wikipedia.org/wiki/Herschel_Space_Observatory https://en.wikipedia.org/wiki/Herschel_Space_Observatory
  - rsynnott 9y ago
    NASA was involved in Herschel to an extent.
kirykl 9y ago
Seems like this is the same problem/discussion a distant civilization would have with Voyager
- oscargrouch 9y ago
  Or it would become a sentient being somehow while in deep space and haunt us back in 2271. V'GER ..
  - deleted 9y ago
    [deleted]
- kk_cz 9y ago
  Voyager is much smaller, though. Can someone with relevant knowledge tell us if this object would be still detected if it was the same size as Voyager 1?
  - scruple 9y ago
    Would we have detected a Voyager-size or Voyager-like object entering our solar system? I really, really doubt it.
arnaudsm 9y ago
Relevant XKCD : https://xkcd.com/1919/ https://xkcd.com/1919/
Santosh83 9y ago
Is there any possibility we could launch a really fast space probe that could overtake this object and report back, maybe within the next decade or so? Do we have the technology now to pull alongside this rock (and it's going to be slowing down)?
- api 9y ago
  Probably. Strap a big overpowered upper stage behind a little lightweight payload and you can fire something pretty fast.
  - valuearb 9y ago
    Unfortunately it's almost impossible at this point. The object passed pedigree a while ago and is headed back out, earth is in a very poor position for an intercept. The calculations I've seen say even if you use the largest possible booster, the SLS (which doesn't exist now, won't exist for another 3 years, if ever) it couldn't even get a small probe to catch up for a very long time, if ever. There may be options in using Jupiter for slingshot maneuvers to overcome our bad positioning, and using super advanced hall effect motors, or project slingshot type probes. But it seems pretty slim at this point. UPDATE: The reddit thread has this comment "Not a chance. Velocity relative to the sun is presently > 39 km/sec and relative to the earth is > 64 km/sec. This is far faster than anything we have ever launched or even could plausibly launch in the near future". Which explains why you need Jupiter to redirect your probe so you can have it go only 40Km/sec to catch up, rather than 65 Km/sec direct from earth.
- wiml 9y ago
  I've seen a couple of suggestions for ways we could theoretically catch it. One is high-Isp rocket motors, which I think would have to be nuclear-thermal like NERVA. If we had one of those already lying around, it might be possible to catch up. The other possibility I've seen discussed are extremely lightweight probes — chip-scale probes weighing less than a gram — accelerated by zillion-gigawatt laser arrays on Earth (or maybe in low Earth orbit). Since those probes don't have to carry their own fuel, they can reach much higher speeds, a sizable fraction of the speed of light, and could catch up to 'Oumuamua even if it took us a few years to develop the technology. Neither of those are technologies we have (though we did build and test some NERVA prototypes back in the day) but they are things that we, as a civilization, could plausibly develop.
kurosawa 9y ago
monolith
- sctb 9y ago
  As much as I like Kubrick, do you mind commenting substantively instead? https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newsguidelines.html

143 points by okket 9y ago

Say whatever you want, I know it is Silkie spaceship.

>It’s also our first direct look at an intact visitor (as opposed to dust specks) from another solar system. Would it not be possible to calculate the origin system based on speed, trajectory, star positions?

rothbardrand 9y ago
I don't think so... it slungshot around the sun, which implies that its in a very large sun oriented orbit. (eg: some random object passing bit for the first time would be likely only slightly disturbed by the suns gravity, not coming so close to it... the latter seems to imply it has been caught by the suns gravity.... or just happened to be aimed nearly directly at the sun.)
- Taniwha 9y ago
  No, they distinctly say it is hyperbolic, not an ellipse, so not orbiting the sun
dangerbird2 9y ago
The problem is that the star positions change over time via galactic orbit. 'Oumuamua's trajectory appears to originate from Vega, but Vega would have been at a different position in relation to our solar system back when 'Oumuamua was at the same distance from the Sun as Vega.
- deleted 9y ago
  [deleted]
QAPereo 9y ago
Not only is the system in question dynamic, as another pointed out, but also subject to perturbations. Worse, orbital mechanics with many bodies is chaotic, in the strict sense.

singularity2001 9y ago

tell me it's no the vanguard of a galactic police squad coming to arrest humans for universal misconduct

DanielleMolloy 9y ago

Here is the random astronomer on Reddit claiming that the community didn't rule out that it is an abandoned spaceship yet: https://amp.reddit.com/r/space/comments/7ealls/solar_systems_first_interstellar_visitor_with_its/ https://amp.reddit.com/r/space/comments/7ealls/solar_systems... "Astronomer here! I will never say this lightly, but we are, swear to God, actually discussing with some seriousness right now what are the odds that this was actually a spaceship. Which I 100% assure you has never happened before in my memory with seriousness."

erikb 9y ago
Why the hack do you assume it's abandoned? It can be full of lifeforms even and we are just not able to see them, talk to them, etc. Imo at this point any assumption is closing in too much. We don't have a definiton of "life" that for sure would include extraterrestrial lifeforms that are not actors with masks in star trek, right?
- paulmd 9y ago
  Well, it's tumbling end-over-end which suggests that if it's a spaceship, it's no longer in control. The discussion around the possibility of it being a spaceship rests on the idea that long thin cigar-shaped objects are the most efficient way to travel in space because it minimizes your need for ablative protection from interstellar dust/etc. But if you're tumbling end-over-end you've thrown that advantage away, so presumably that's not a thing you would intentionally do. And if you are assuming that this spaceship has shields or whatever, then there is no reason they would be restricted to a cylindrical shape. It could be a discarded booster stage or fuel tank, of course. Maybe they were trying to drop it into the sun and missed. Or a a mass-driver shot (maybe they finally took care of that pesky Russell's Teapot for us...) The presumptive conclusion is of course that it's a natural phenomenon, but it sure is a weird object, and unless we can find a way to catch it (or any future objects) we will never know. Maybe a starshot probe could catch it?
  - deleted 9y ago
    [deleted]

Voloskaya 9y ago

> Occam’s Razor says it’s unlikely that the very first object we ever see from interstellar space just happens to be a spaceship. Well, isn't this kind of self fulling thing? Because we assume first that this is an interstellar asteroid, then the following statement is "proven": > Researchers had long theorized that space should be full of comets and asteroids ejected from other solar systems during their early days. Their models showed that planetary formation is a messy business, with many small objects kicked out as big proto-planets form. `Oumuamua is the first proof that they were right And at this point, yes, it appears very unlikely that the first interstellar object we meet would be artificial. But if we start by saying we don't know what it is, then the above theory is just speculation, and might be false (what if planeraty formation is a clean process?). If the theory above can be false, then it could make sense that the first interstellar object we encounter would be artificial, no? It seems to me that Occam's Razor doesn't tell us much in this instance.

nuclx 9y ago
What I thought. The absence of a priori knowledge prohibits the application of Occam's Razor in this case.
- deleted 9y ago
  [deleted]
hyperpallium 9y ago
Unfortunately, Occam's Razor can say whatever you want by fiddling the apriori probabilities. Here, the probability you need is how likely that theory is to be true - just because it could be false doesn't mean it's 50-50. If all the models show planet formation is messy, it seems reasonable to estimate its probability as much greater than 0.5 (note that even if it's 0.9999, they still could be wrong).
- Voloskaya 9y ago
  Totally agree. My point is just that I find it a bit weird/circular to use Oumuamua as the `first proof` for a theory that is subsequently used with Occam's Razor to demonstrate that Oumuamua is likely not something else.

hectorlorenzo 9y ago

These actually sound like last famous words.

joering2 9y ago

What's really shocking is the drawing from the article [1] This Astroid was Discovered when already passed by the Earth!! And was actually very close to it! While I am pretty certain Astronomers knew it won't hit us, the amount of time it took to discover it would be way too late for us to even hold hands and kiss our children goodbye! http://blogs.discovermagazine.com/outthere/files/2017/11/eso1737c.jpg http://blogs.discovermagazine.com/outthere/files/2017/11/eso...

grkvlt 9y ago
Well, if it had hit Earth, it would have happened without astronomers (or anyone else) knowing about it beforehand. As you point out, it was discovered after it had passed us, so there was no advance warning at all, however this is quite common with asteroids.
valuearb 9y ago
The earth gets hit by similarly sized asteroids every 30,000 to 100,000 years, albeit not quite at this velocity. Average impact velocity for asteroids from our system is 17 Km/sec, so about 2/3s the speed of this visitor. Either way, it's not even close to an extinction event. And "very close to it" is a misnomer. It came within 24 million kilometers of Earth, about 60 times farther away than the moon is.

sebow 9y ago

This guy is definitely obsessed with aliens

jfindley 9y ago

Are there yet any credible theories for why we see so few of these? AIUI, if we're correct about how planets form, there should be far more of these than we're seeing. Is it that we're probably wrong about how planets form, or there's something strange about our part of the galaxy, something else or do we just have no clue?

dr_zoidberg 9y ago
The general consensus amongst astronomers is that these objects are far too faint to be seen. As more sensitive instruments are developed/deployed, we should begin seeing more of them.
Voloskaya 9y ago
Estimate is that there might be about ~10 of these object passing through every year, so it's not a lot to start with. In addition asteroids are relatively small and hard to spot since they are inert. We managed to spot this one because we were lucky it came so close to earth.

splittingTimes 9y ago

So why exactly can we not get a better look at it as it is leaving? With all our earth- and spacebound telescopes [1] (some are sitting at Earth-Sun Lagrange points) I would imagine we could. Being too far away behind the sun seems an unlikely argument to me. === [1] https://en.wikipedia.org/wiki/List_of_space_telescopes https://en.wikipedia.org/wiki/List_of_space_telescopes

grkvlt 9y ago
The only working telescope at a Lagrange point is Gaia [0] at Earth-Sun L2, but it is an astrometry instrument, designed to measure the position and brightness of various stars, rather than generic deep-space imaging. The Herschel Space Observatory [1] is also at the Earth-Sun L2 point, and has a 3.5m IR telescope, but ran out of coolant in 2013 and is now defunct. Interestingly, these are both ESA missions, not NASA. 0. https://en.wikipedia.org/wiki/Gaia_(spacecraft) https://en.wikipedia.org/wiki/Gaia_(spacecraft) 1. https://en.wikipedia.org/wiki/Herschel_Space_Observatory https://en.wikipedia.org/wiki/Herschel_Space_Observatory
- rsynnott 9y ago
  NASA was involved in Herschel to an extent.

kirykl 9y ago

Seems like this is the same problem/discussion a distant civilization would have with Voyager

oscargrouch 9y ago
Or it would become a sentient being somehow while in deep space and haunt us back in 2271. V'GER ..
- deleted 9y ago
  [deleted]
kk_cz 9y ago
Voyager is much smaller, though. Can someone with relevant knowledge tell us if this object would be still detected if it was the same size as Voyager 1?
- scruple 9y ago
  Would we have detected a Voyager-size or Voyager-like object entering our solar system? I really, really doubt it.

arnaudsm 9y ago

Relevant XKCD : https://xkcd.com/1919/ https://xkcd.com/1919/

Santosh83 9y ago

Is there any possibility we could launch a really fast space probe that could overtake this object and report back, maybe within the next decade or so? Do we have the technology now to pull alongside this rock (and it's going to be slowing down)?

api 9y ago
Probably. Strap a big overpowered upper stage behind a little lightweight payload and you can fire something pretty fast.
- valuearb 9y ago
  Unfortunately it's almost impossible at this point. The object passed pedigree a while ago and is headed back out, earth is in a very poor position for an intercept. The calculations I've seen say even if you use the largest possible booster, the SLS (which doesn't exist now, won't exist for another 3 years, if ever) it couldn't even get a small probe to catch up for a very long time, if ever. There may be options in using Jupiter for slingshot maneuvers to overcome our bad positioning, and using super advanced hall effect motors, or project slingshot type probes. But it seems pretty slim at this point. UPDATE: The reddit thread has this comment "Not a chance. Velocity relative to the sun is presently > 39 km/sec and relative to the earth is > 64 km/sec. This is far faster than anything we have ever launched or even could plausibly launch in the near future". Which explains why you need Jupiter to redirect your probe so you can have it go only 40Km/sec to catch up, rather than 65 Km/sec direct from earth.
wiml 9y ago
I've seen a couple of suggestions for ways we could theoretically catch it. One is high-Isp rocket motors, which I think would have to be nuclear-thermal like NERVA. If we had one of those already lying around, it might be possible to catch up. The other possibility I've seen discussed are extremely lightweight probes — chip-scale probes weighing less than a gram — accelerated by zillion-gigawatt laser arrays on Earth (or maybe in low Earth orbit). Since those probes don't have to carry their own fuel, they can reach much higher speeds, a sizable fraction of the speed of light, and could catch up to 'Oumuamua even if it took us a few years to develop the technology. Neither of those are technologies we have (though we did build and test some NERVA prototypes back in the day) but they are things that we, as a civilization, could plausibly develop.

kurosawa 9y ago

monolith

sctb 9y ago
As much as I like Kubrick, do you mind commenting substantively instead? https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newsguidelines.html