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Alien Comet May Have Infiltrated the Solar System
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."
, 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 ;)
Colorless green Cthulhu waits dreaming furiously.
What that line is that runs parallel to the comet from the centre of the sun to the bottom left of the image?
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 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.
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.
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.
Who made who ?
Who made you?
No fence, but a few light years (4.2 to Proxima Centauri) between the nearest solar system means that either this is a very very slow moving comet and we've just not seen it before or it's been travelling for a few thousand/million years to get here..
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 results.
Aint nobody told you?
Under the assumption that it has no propulsion of its own, it should be easy to determine where it came from. That's the beauty of the vacuum of space... things move rather predictable. So predictable in fact that the position of all kinds of objects is known for the next couple of centuries. We should be able to make a stab at where this thing came from.
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 energy to prevent escape from our solar system.
Wouldn't it be wild if an alien race was trying to send us a message, and instead of a message in a bottle, it was a message in a comet?
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.
If builders built buildings the way programmers wrote programs, then the first woodpecker would destroy civilization.
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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