Author Topic: Hyperbolic Hyperbole or Interstellar Interloper? ('Oumuamua)  (Read 77376 times)

Offline Star One

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Re: Hyperbolic Hyperbole or Interstellar Interloper?
« Reply #180 on: 11/21/2017 08:23 pm »
The only reason that I even suggested that the asteroid might have a high metal content is due to it's unusual shape.  Typical asteroids in our solar system tend to be more rounded, rather than long and angular.
While "rubble piles" are common, small asteroids that appear to be individual, cohesive fragments are known. Rocks can do this just as well as metal. X type is within the error bars of the colors in Bannister's paper, so yeah, it could be metallic, but it could be a lot of other stuff too.

Some people (not you) seem to want jump from "could be metallic composition" to "metallic = probably a spaceship!" which isn't really suggested by any of the available data 

Your second paragraph is unsupportable at this early stage. Unless you’re suggesting you’ve been out to look at it.
« Last Edit: 11/21/2017 08:23 pm by Star One »

Offline Star One

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Re: Hyperbolic Hyperbole or Interstellar Interloper?
« Reply #181 on: 11/21/2017 08:25 pm »

Offline Thorny

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Re: Hyperbolic Hyperbole or Interstellar Interloper?
« Reply #182 on: 11/21/2017 08:29 pm »
Image has been updated:
That looks so much like "The Doomsday Machine", Trekkies are gonna have a field day.

Offline KelvinZero

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Re: Hyperbolic Hyperbole or Interstellar Interloper?
« Reply #183 on: 11/21/2017 08:36 pm »
Image has been updated:
That looks so much like "The Doomsday Machine", Trekkies are gonna have a field day.
It wouldn't be out of place in a Cheech and Chong movie, either.  8)
« Last Edit: 11/21/2017 08:38 pm by KelvinZero »

Offline hop

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Re: Hyperbolic Hyperbole or Interstellar Interloper?
« Reply #184 on: 11/21/2017 08:39 pm »
Shouldn't some specific protocol be created to quickly and efficiently respond, if an event like this were to happen again in the future?
There is: Interesting objects get an MPEC  and then every astronomer on twitter points whatever they've got at it ;)

More seriously, the NEO and transient astronomy (supernova, GRB etc) communities already have procedures established for rapid follow up. If you look at the papers that have already come out, a good fraction of the largest telescopes on Earth were looking at this thing within days of it being recognized as clearly interstellar. Directors discretionary time was also awarded quickly on Hubble and Spitzer.

It's also important to keep in mind is that it takes time to confirm that an object is actually interesting. If everyone dropped what they were doing when preliminary data looked a bit funny, nobody would get much done.
Quote
If another Interstellar object comes through our solar system again, then wouldn't it benefit us to detect it at the earliest, and then start taking detailed measurements of it as soon as possible? The data could provide valuable insights on the universe beyond our solar system.
Absolutely, but it's not clear to me there were major shortcomings this time around.

One thing I have seen mentioned is that the existing NEO detection pipelines aren't optimal for detecting objects like this, so it's possible software improvements could help us find more.
« Last Edit: 11/21/2017 08:40 pm by hop »

Offline Star One

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Re: Hyperbolic Hyperbole or Interstellar Interloper?
« Reply #185 on: 11/21/2017 11:06 pm »
Quote
Jason Wright
@Astro_Wright
Replying to @davidwhogg
The paper I am considering is a short research note discussing the (im)possibility is was scattered in from the Oort Cloud by a distant planet.

Why is it *likely* artificial?!? It’s low on my list of potentially artificial anomalies.

https://mobile.twitter.com/Astro_Wright/status/933096998072344576

Offline JasonAW3

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Re: Hyperbolic Hyperbole or Interstellar Interloper?
« Reply #186 on: 11/21/2017 11:23 pm »
Image has been updated:

Ok, is that an actual update, (highly unlikely) or some Photoshopped image? (Likely)
My God!  It's full of universes!

Offline Mongo62

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Re: Hyperbolic Hyperbole or Interstellar Interloper?
« Reply #187 on: 11/22/2017 01:08 am »
1I/2017 U1 (Oumuamua) Might Be A Cometary Nucleus

Since the photometry has not been able to detect a coma or a tail, the current consensus is that we are in the presence of an asteroid, whose colors are comparable to those of excited objects of the Kuiper belt or less-red Jupiter Trojans (Bannister et al., 2017), consistent with Kuiper belt colors (Masiero, 2017), colors overlapping the mean colors of D-type Trojan asteroids and other inner solar system populations, and inconsistent with the ultra-red matter found in the Kuiper belt (Jewitt et al., 2017).

In this work we find evidence that the object is of cometary origin.

[...]

The diagrams shows that colors of cometary nuclei fall inside an irregular ellipsoid, but 70% of them fall on a tilted line that we call *the main sequence of cometary nuclei colors*, MS. Plotting the above three observed colors of 1I/2017 U1 on the diagrams shows that the values lie on the MS. This suggests that 1I/2017 U1 is a cometary nucleus.

The next question is if this is an active or an extinct cometary nucleus.

Deep imaging by Meech (2017) failed to show a coma, but we can not exclude the possibility that this was an active comet because there were no observations at or near perihelion (the object was discovered +39 days past perihelion). Some low level cometary nuclei have very short periods of activity. As an example 107P/Wilson-Harrington was active for only 35±5 days (Ferrín et al., 2017).

One implication of this result is that then we do not know from where the object came. It may have come from the inner planetary region, from a local main belt, from the nearby region of a local Jupiter or from the Oort cloud of the parent star.
« Last Edit: 11/22/2017 01:09 am by Mongo62 »

Offline Patchouli

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Re: Hyperbolic Hyperbole or Interstellar Interloper?
« Reply #188 on: 11/22/2017 01:33 am »
I'm convinced:

Actually Blackstar... I'm more thinking along the lines of a Zentradi Warship from Robotech/Macross. :)
Same here.
« Last Edit: 11/22/2017 01:42 am by Patchouli »

Online jebbo

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Re: Hyperbolic Hyperbole or Interstellar Interloper?
« Reply #189 on: 11/22/2017 07:13 am »
XKCD nails it

https://xkcd.com/1919/

So can we stop with the silly spacecraft

/killjoy

--- Tony

Offline Star One

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Re: Hyperbolic Hyperbole or Interstellar Interloper?
« Reply #190 on: 11/22/2017 07:28 am »
XKCD nails it

https://xkcd.com/1919/

So can we stop with the silly spacecraft

/killjoy

--- Tony

And this paragraph seems just as applicable here as elsewhere.

Quote
Skepticism still rules the day when it comes to these headlines, and the events that spawn them. That’s the way it should be, because we’ve always found a more prosaic reason for whatever signal from space we’re talking about. But, being skeptical is a balancing act; it doesn’t mean being dismissive.

https://futurism.com/either-stars-are-strange-or-234-alien-species-are-trying-to-contact-us/
« Last Edit: 11/22/2017 08:14 am by Star One »

Offline KelvinZero

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Re: Hyperbolic Hyperbole or Interstellar Interloper?
« Reply #191 on: 11/22/2017 09:22 am »
So can we stop with the silly spacecraft
The clip above also estimates 10,000 such objects in the solar system at a given time, spending about 10 years passing through, meaning about 1000 new objects enter the solar system each year. So I guess we can also stop worrying too much about this one getting away from us.

Hey, how about this:

Unless Im confused, this is a different NON-interstellar example of a highly elongated asteroid that we have actually imaged.
https://www.jpl.nasa.gov/spaceimages/details.php?id=PIA20280
(this might have been the one already mentioned, but this is the first time I saw the image)

Just looking at that, there must be a process that forms such shapes, and if someone could explain the process it might be obvious why the process would apply even more in interstellar space. (less solar wind? less nudging by passing gravitational fields?)

(edit -- added later)
This link has some possibly relevant speculation. I expect less erosion from grit in interstellar space:
https://www.space.com/5587-strange-asteroid-shapes-explained.html
But what changes the asteroids' shape? Gyula and his team have shown that asteroids change shape from elongated to roughly spherical due to being impacted during their lifetimes. They are like pebbles on the beach that become worn smooth over many years -- only in space, erosion is caused by small impacts as rocks knock into each other and chip pieces off.
« Last Edit: 11/22/2017 10:18 am by KelvinZero »

Offline Star One

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Re: Hyperbolic Hyperbole or Interstellar Interloper?
« Reply #192 on: 11/22/2017 09:48 am »
So can we stop with the silly spacecraft
The clip above also estimates 10,000 such objects in the solar system at a given time, spending about 10 years passing through, meaning about 1000 new objects enter the solar system each year. So I guess we can also stop worrying too much about this one getting away from us.

Hey, how about this:

Unless Im confused, this is a different NON-interstellar example of a highly elongated asteroid that we have actually imaged.
https://www.jpl.nasa.gov/spaceimages/details.php?id=PIA20280
(this might have been the one already mentioned, but this is the first time I saw the image)

Just looking at that, there must be a process that forms such shapes, and if someone could explain the process it might be obvious why the process would apply even more in interstellar space. (less solar wind? less nudging by passing gravitational fields?)

Or it’s just a shattered shard off a much bigger object.

Online jebbo

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Re: Hyperbolic Hyperbole or Interstellar Interloper?
« Reply #193 on: 11/22/2017 09:51 am »
The clip above also estimates 10,000 such objects in the solar system at a given time, spending about 10 years passing through, meaning about 1000 new objects enter the solar system each year. So I guess we can also stop worrying too much about this one getting away from us.

Yup.  From how long it took to spot this current one with Pan-STARS, I've seen estimates (I'll see if I can dig it out) that this means we should detect about 1 a year with the LSST when it's available.
 
Quote
Unless Im confused, this is a different NON-interstellar example of a highly elongated asteroid that we have actually imaged.
https://www.jpl.nasa.gov/spaceimages/details.php?id=PIA20280
(this might have been the one already mentioned, but this is the first time I saw the image)

Yes, that's an interesting one.

Quote
Just looking at that, there must be a process that forms such shapes, and if someone could explain the process it might be obvious why the process would apply even more in interstellar space. (less solar wind? less nudging by passing gravitational fields?)

I suspect there is more than one mechanism for forming elongated objects.  Solar system objects like 2003 SD220 (that you linked), which are slow rotators (285 hours), can form relatively easily by slow speed collisions and they can be made of ice/rubble/etc.

However, 'Oumuamua rotates quickly (~8 hours), which requires structural strength (hence speculation about metallic composition; though rocky works just as well).

BTW, these things almost certainly *don't* form in interstellar space, but are ejected from systems as they are forming.  One of the speculations for 'Oumuamua is was formed from molten ejecta from an energetic planet/planet collision (there are others).

From the approach angle and velocity, it is was very travelling at close to the Galactic LSR (local system of rest; i.e. drifting around the galaxy) which probably means a distant origin (in time and distance).  [ This suggests to me that a fruitful way of finding these might be staring at the solar apex ]

Quote from: Star One
Or it’s just a shattered shard off a much bigger object.

I don't think a direct fragment is likely, but a heavily processed one (i.e. it melted) is possible

--- Tony
« Last Edit: 11/22/2017 09:55 am by jebbo »

Online jebbo

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Re: Hyperbolic Hyperbole or Interstellar Interloper?
« Reply #194 on: 11/22/2017 10:45 am »
First data from Hubble can be found here https://archive.stsci.edu/proposal_search.php?id=15405&mission=hst

--- Tony

Offline Star One

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Re: Hyperbolic Hyperbole or Interstellar Interloper?
« Reply #195 on: 11/22/2017 10:55 am »
The clip above also estimates 10,000 such objects in the solar system at a given time, spending about 10 years passing through, meaning about 1000 new objects enter the solar system each year. So I guess we can also stop worrying too much about this one getting away from us.

Yup.  From how long it took to spot this current one with Pan-STARS, I've seen estimates (I'll see if I can dig it out) that this means we should detect about 1 a year with the LSST when it's available.
 
Quote
Unless Im confused, this is a different NON-interstellar example of a highly elongated asteroid that we have actually imaged.
https://www.jpl.nasa.gov/spaceimages/details.php?id=PIA20280
(this might have been the one already mentioned, but this is the first time I saw the image)

Yes, that's an interesting one.

Quote
Just looking at that, there must be a process that forms such shapes, and if someone could explain the process it might be obvious why the process would apply even more in interstellar space. (less solar wind? less nudging by passing gravitational fields?)

I suspect there is more than one mechanism for forming elongated objects.  Solar system objects like 2003 SD220 (that you linked), which are slow rotators (285 hours), can form relatively easily by slow speed collisions and they can be made of ice/rubble/etc.

However, 'Oumuamua rotates quickly (~8 hours), which requires structural strength (hence speculation about metallic composition; though rocky works just as well).

BTW, these things almost certainly *don't* form in interstellar space, but are ejected from systems as they are forming.  One of the speculations for 'Oumuamua is was formed from molten ejecta from an energetic planet/planet collision (there are others).

From the approach angle and velocity, it is was very travelling at close to the Galactic LSR (local system of rest; i.e. drifting around the galaxy) which probably means a distant origin (in time and distance).  [ This suggests to me that a fruitful way of finding these might be staring at the solar apex ]

Quote from: Star One
Or it’s just a shattered shard off a much bigger object.

I don't think a direct fragment is likely, but a heavily processed one (i.e. it melted) is possible

--- Tony

Wouldn’t even a planetary collision struggle to impart sufficient energy to an object of this type for it achieve sufficient velocity to escape a planetary system.

We really need a telescope high above the plane of the solar system (and another below it) looking for objects coming in from the galactic centre. Being as the stellar density increases markedly in that direction I would expect a steady stream of flotsam and jetsam.
« Last Edit: 11/22/2017 11:00 am by Star One »

Online jebbo

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Re: Hyperbolic Hyperbole or Interstellar Interloper?
« Reply #196 on: 11/22/2017 11:04 am »
Wouldn’t even a planetary collision struggle to impart sufficient energy to an object of this type for it achieve sufficient velocity to escape a planetary system.

Yes, but my point is that things ejected by such collisions would probably be melted, rather than being mere splinters of the original bodies.  And because they are molten, you can imagine tidal forces resulting in elongation.

Quote
We really need a telescope high above the plane of the solar system looking for objects coming in from the galactic centre. Being as the stellar density increases markedly in that direction I would expect a steady stream of flotsam and jetsam.

Unlikely.  Objects from the inner galaxy have a big gravitational hill to climb.  We are much more likely to find objects that share roughly the same orbit as the sun around the galaxy.  Such objects will most likely approach from roughly the solar apex (think Vega).

--- Tony

Offline Ben the Space Brit

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Re: Hyperbolic Hyperbole or Interstellar Interloper?
« Reply #197 on: 11/22/2017 11:04 am »
I'm convinced:

Personally, I think that it looks a lot like how I visualised Rama.
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Offline Star One

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Re: Hyperbolic Hyperbole or Interstellar Interloper?
« Reply #198 on: 11/22/2017 12:11 pm »
Wouldn’t even a planetary collision struggle to impart sufficient energy to an object of this type for it achieve sufficient velocity to escape a planetary system.

Yes, but my point is that things ejected by such collisions would probably be melted, rather than being mere splinters of the original bodies.  And because they are molten, you can imagine tidal forces resulting in elongation.

Quote
We really need a telescope high above the plane of the solar system looking for objects coming in from the galactic centre. Being as the stellar density increases markedly in that direction I would expect a steady stream of flotsam and jetsam.

Unlikely.  Objects from the inner galaxy have a big gravitational hill to climb.  We are much more likely to find objects that share roughly the same orbit as the sun around the galaxy.  Such objects will most likely approach from roughly the solar apex (think Vega).

--- Tony

But as the Sun orbits the galactic centre it doesn’t stay static within the galactic plane but ‘bounces’ up and down so surely it will encounter things in different planes, some of these more favourable for material from the galactic centre I would have thought.

Offline TakeOff

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Re: Hyperbolic Hyperbole or Interstellar Interloper?
« Reply #199 on: 11/22/2017 01:42 pm »
With all the binary stars around, there's alot more gravity power around than a fly by of a migrating Jupiter to get these things going all over the place. A comet/asteroid/whatever in a chaotic orbit might flyby both stars and get ejected, and dries out in a close encounter to never show a coma again. However, this one was pretty slow relative to the stellar neighborhood (of Vega) AFAIK.
« Last Edit: 11/22/2017 01:45 pm by TakeOff »

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