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Alien Comet May Have Infiltrated the Solar System
Posted by
kdawson
on Wed Dec 03, 2008 05:37 AM
from the starseed-lure dept.
from the starseed-lure dept.
New Scientist has a piece about Comet Machholz 1, whose uncommon molecular composition suggests, but does not prove, that it may be an interloper from another star system. "Comet Machholz 1 isn't like other comets. David Schleicher of the Lowell Observatory in Flagstaff, Arizona, measured the chemical makeup of 150 comets, and found that they all had similar levels of the chemical cyanogen (CN) except for Machholz 1, which has less than 1.5% of the normal level. Along with some other comets, it is also low on the molecules carbon-2 and carbon-3."
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Oh, no, Alien Comet! (Score:5, Funny)
Re: (Score:3, Funny)
it could be worse - imagine all of the trucks suddenly freaking out.
Re:Oh, no, Alien Comet! (Score:5, Insightful)
It's hardly surprising that we actually can get objects that originates from outside our solar system. There isn't much of a fence around the solar system.
What could be really interesting is to pick samples from this comet to check for more complex molecules. It's not really that we have seen our "own" comets all the way through yet, so we don't know much about possible variations.
We don't even know much about how the comets were created, and that means that there is a lot of uncertainty involved. A possible scenario is that the comets originates from a larger object that has cracked up, which may explain why most of them are similar in composition and that this new comet is from another source. Just compare the variations in composition of the planets we have in the solar system.
There is still so much to learn about the universe.
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Re:Oh, no, Alien Comet! (Score:5, Insightful)
There are no fences, but to a significant gravitational barrier to overcome when leaving the original star system. Also, to fall into orbit around or sun would require a third body to take away the excess energy. I guess this could be one of our planets, but on overall I'm suspecting more "boring" origins, such as a cold spot in our own solar system.
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Re: (Score:3, Funny)
...I'm suspecting more "boring" origins, such as a cold spot in our own solar system.
My first ex-girlfriend made this?
Re:Oh, no, Alien Comet! (Score:4, Interesting)
Just as well as there are comets that are bent on a course inward to a gravity well there can as well be comets that are thrown out of the gravity well.
If you just look at how Jupiter was used as a slingshot tool for the Voyager probes that can as well happen with a comet. The universe is filled with unpredictable events and even if an event is statistical unlikely the immense size of the universe makes it happen anyway.
The origin of the comets is still very uncertain, we can't be sure that they are the remains of the creation of the solar system - they may actually be some of the base material that it was created from. And as for traveling (Whiternoise's comment) the comets have had a lot of time to travel. A few billion years is no big deal in the depths of space.
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Re: (Score:3, Interesting)
As for chemical composition, it's relatively easy to guess what comets are made of through spectral analysis - and most of the universe probably runs on the same sorts of atomic combinations. However, actually picking samples would certainly yield better res
Re:Oh, no, Alien Comet! (Score:5, Informative)
the Oort cloud, hypothesized to be the source of all comets.
Actually the very existence of the Oort cloud is hypothetical. While it provides a reasonable explanation for the existence of comets in our system there was no further independent confirmation until 2000, when more powerful telescopes identified one object that could belong to the cloud. Given that the number of comets could be into the trillions, having found a handful does not constitute definitive evidence, so it remains a mere hypothesis until more data is gathered.
For a foreign body to enter the system, it would have to pass through the Oort cloud and that would be highly unlikely. It's most probably an Oort cloud comet of a new type.
Comets in the Oort cloud are tens of millions of kilometers apart. An exo-solar comet would have no problem "sneaking" in.
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Re: (Score:3, Interesting)
Re: (Score:3, Funny)
Wouldn't it be even more wild if the message was: "You die now!!"
Re:Oh, no, Alien Comet! (Score:4, Interesting)
How dense do you think this theorized cloud of comets is?
It's not a matter of density as much as it is of gravity and orbital dynamics.
There are 2 clouds, the Inner and Outer.
The inner cloud is not as susceptible to extra-solar gravitational forces as the outer. The outer bodies can be pulled away from the cloud which is about 1 light year from Sol so the gravitational effects of the sun are very weak.
The Outer cloud 'protects' the inner cloud from intrusion. Any body drawn into the cloud by the cloud's combined gravitational forces would just join the cloud and go no further unless the body was ejected towards the sun at high speed., which as I said before is highly unlikely as any captured body would just join the cloud.
The Inner cloud is closer and is the theoretical source of our system's comets. It is unlikely but possible that an outer cloud body would enter the inner cloud's realm.
A body that is dislodged from the inner cloud due to random collisions by its neighbors, enters the solar system and becomes a comet.
So for an extra-solar system body to enter into the system, it has to pass through 2 gravity wells (the Outer and Inner clouds) and be directed (velocity approaching) the sun.
The other aspect is that these cloud bodies are the remnants of the formation of our Solar System which would include a variety of different compositions. Eventually all these left-overs will be drawn together and inwards to the sun.
This theory was explained to me by an astronomer from Kansas U. in 1976(?) so that's why I mentioned the 30 year bit in my last post.
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Re: (Score:3, Funny)
Oh shut up already. He got +5 for literary style, not correctness.
Mod AC up for wisdom, correctness, clean living and being of fine character.
In related news.. (Score:5, Funny)
Scientists have discovered a Buddhist monk who is not human.
food for thought...
Parent
Well.. (Score:3, Funny)
Re: (Score:3, Funny)
All hail Xenu!
Entry is Free. (Score:5, Funny)
Re:Entry is Free. (Score:5, Insightful)
Me thinks this news smells a bit like trying to get some funding...
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Re:Entry is Free. (Score:4, Insightful)
well, given that comets inhabit the outer reaches of our solar system already, it wouldn't take too much effort. Add in the vastness of space and the fact that gravitational attraction exists I'd conjecture that any body heading in our general direction would be captured by our gravitational pull. It wouldn't have to aim straight at us, just in the general vicinity.
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Not really (Score:3, Informative)
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If had enough velocity to escape its home system, it wouldn't be captured by "us" either.
What kind of physicist? You should know good and well several things:
1) An object could leave the solar system with a final asymptotic speed of, say, 1m/sec relative to our sun. Or 100m/sec. Or 10km/sec. It depends on its initial speed, position, and path out of the solar system. The quoted statement here is simply nonsensical.
2) Even if an object left our solar system going 100km/sec, that's only the speed relative to our sun. That says nothing about its speed relative to another sun. Just because mo
Re:Entry is Free. (Score:5, Informative)
The Sun alone can't capture a 'stray' comet - it'll just give it a gravity assist. You need at least three-bodies interaction for the orbital capture.
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Re:Entry is Free. (Score:5, Funny)
I could go for some three-bodies interaction.
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Re: (Score:3, Interesting)
Well, the comet was one body, the Sun is another, and we have eight planets that are serviceable candidates for the third body. (Though some are better candidates than others.)
Or, the approach vector was such that the solar system's net gravitational pull attracted it into the Oort cloud where impacts with other bodies slowed it down, taking enough of its e
Re:Entry is Free. (Score:5, Funny)
African or European?
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Re:Entry is Free. (Score:5, Funny)
Is the comet carrying coconuts?
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Re: (Score:3, Insightful)
escape is really not a problem. Much of the "stuff" in our solar system was ejected into space as it foormed. Planets that were to close were either ejected or landed in the Sun. Today all that is left are the bits that were in stable orbits the rest is long gone. The fact that this could have been ejected from it's home is not a big deal but (1) the chance that it got here and (2) that it went into orbit around the sun are a (maybe) one in a billion chance. But then with a few billion commets a one i
Re:Entry is Free. (Score:5, Informative)
Besides that, how would it have come here anyway? What is the escape velocity for getting out of a star system?
There is nothing mysterious or difficult to believe here.
We see about four comets per century that have hyperbolic trajectories - that is to say, they are never coming back.
These hyperbolic comets are either interstellar interlopers already and have not been captured by the solar system (which would typically occur by losing part of its kinetic energy to one of the gas giants through gravitational interaction), or they are solar system comets being ejected into interstellar space (through gaining energy by the same mechanism) to become future interlopers in other star systems. Either way, we see the effect of comet ejection regularly, every few decades.
Since the Oort Cloud is much denser with comets compared to the density of wandering comets in interstellar space, most hyperbolic comets are going to be the latter type.
Machholz 1, if it is alien, was captured by the solar system some time in the past. Although this type of capture may be rare, since it would be going on since the formation of the solar system a substantial population of alien comets should have built up by this time, and captured aliens may be a more common sight than one-shot hyperbolic visitors.
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Alien bastards (Score:4, Funny)
Re:Alien bastards (Score:4, Funny)
Dek uur deeewww!!! [youtube.com]
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Re:Alien bastards (Score:4, Funny)
They're just doing the jobs that lazy Solar System comets refuse to do. Besides, it's the hard working, entrepreneurial comets that are willing to travel a trillion miles for a chance at a better life for themselves and their satellite debris that made this star system great.
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Re:Alien bastards (Score:4, Funny)
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Determining origin (Score:4, Insightful)
Besides, its only speculation that suggests it didn't come from our own Kuiper belt in the first place - we don't know enough about that to be sure.
Re:Determining origin (Score:5, Interesting)
Lets face it, even if we retrieved a sample and analysed it in a lab, we wouldn't be able to say with any real certainty where it came from.
With an actual sample, and isotope analysis, we could say whether or not it came from this solar system. This is done all of the time for tiny grains found in meteors and collected directly, some of which do not come from this solar system [skyandtelescope.com].
True, saying where it did come from might require sampling most of the star systems in our region of the galaxy and that will take... a while.
Parent
Re:Determining origin (Score:4, Informative)
Videos here [nasa.gov] illustrate the effects of the comet's (abnormal) very close trajectory to the sun. Collected dust is pretty much sandblasted away on a regular base.
But since it doesn't contain assembly language I don't really know what I'm talking about.
Parent
Some guys just got less CN than others (Score:3, Interesting)
, which has less than 1.5% of the normal level.
Um, that doesn't sound like an indication of its alien origin.
The story could go like this: Long long ago, a large comet that had roughly the same concentration of CN as an average one, broke up into 2 pieces. Because the substances are not uniformly distributed over the big comet, one of the pieces happen to have more CN than the other. The one with richer CN then got blown to pieces in a collision of some kind, while the one with less CN survived.
And no, I didn't read TFA ;)
Re: (Score:3, Interesting)
Does anybody know (Score:4, Interesting)
What that line is that runs parallel to the comet from the centre of the sun to the bottom left of the image?
Re:Does anybody know (Score:5, Informative)
Parent
Umm, Carbon-2 and Carbon-3? (Score:3, Insightful)
I'm fairly certain that isotopes of carbon with those masses is impossible unless this comet also contains some neat subatomic particles with anti-mass as well.
The original article has it correct with the 2 and 3 as subscripts. Leave isotopic notation to isotopes.
Re:Umm, Carbon-2 and Carbon-3? (Score:5, Informative)
Space chemistry is completely unrelated to "normal" earthly chemistry - for example, the second most popular molcule in the universe is H3+ (after H2).
What is discussed here are molecules composed exclusively of 2 and 3 carbon atoms:
http://en.wikipedia.org/wiki/Diatomic_carbon [wikipedia.org]
http://en.wikipedia.org/wiki/Tricarbon [wikipedia.org]
Parent
This is a long shot (Score:3, Interesting)
Having read the article, the extra-terrestrial origin idea seems like a long shot to me. There is less cyanogen than normal ! Maybe it formed in unusual conditions... or could it be from another solar system ! Note, in all seriousness, that there has never been a firmly established extra-terrestrial "new comet" (on a hyperbolic orbit), so the statistics make this unlikely but certainly not impossible.
I find dwarf-planet Sedna much more intriguing Sedna's orbit is very strange, this orbit probably formed in an 3-body interaction between the Sun, Sedna, and another star and, if so, there is about a 10% chance [arxiv.org] that Sedna was originally in orbit about that other star. If I was NASA administrator, one thing I would certainly try and do would be to send a "Pluto Express" type spacecraft there.
Re: (Score:3, Funny)
I'm fairly sure all comets are extra-terrestrial, what with not being from Earth or its atmosphere.
New Comet Checklist (Score:4, Funny)
Let's see:
1. Kool Aid (it should be blue) - CHECK
2. Cyanide - CHECK
3. Video Cameras to record our ascension to the spaceship that will take us to heaven - CHECK
4. Special freaky "cult blankies" to cover up with so when they find our "empty shell vessels" they know that this was a joyous occasion, and not some weird cult suicide thing - CHECK
I think we're ready....You guys just head to the mansion, there's plenty of kool-aid for everyone, but I olny have 25 futuristic cult blanky death shrouds, so you may want to bring you own, I suggest blue or black, but whatever you do just make sure it doesn't have snoopy or south park or some cartoon character...Star Wars is okay - we're videoing everything.
Re:Nuke it! Nuke it now! (Score:4, Funny)
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Re:Nuke it! Nuke it now! (Score:5, Funny)
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Naquadah (Score:5, Funny)
No, if it's made of naquadah, they'll WANT you to nuke it.
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Re:Naquadah (Score:4, Funny)
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Re:Naquadah (Score:4, Funny)
We need to reverse the polarity on Earth's deflector shields!
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Re: "Screw Star Trek" (Score:3, Funny)
Oldie? would you prefer a "Treehouse" reference lil' one?
Re: (Score:3, Funny)
- So, Mr. ... Machholz 1, you say you got to this star system without a visa by mistake? I'm sure Machholz 2 and 3 would be happy to join us in this beautiful, sucessful star system... right? Tell us the truth... you'd get an ilegal job and start bringing your lazy, alien-speaking relatives, that's the truth, isn't it? Don't lie to me, you foreign scum!