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Comet Catalina To Pass By Earth For the Final Time
StartsWithABang writes: Originating from the Kuiper belt and the Oort cloud, comets are generally thought of as periodic objects, with their initial trajectories having been perturbed by either Neptune, another distant object or a passing star or rogue planet. But most comets aren't periodic; they're transient instead, where a trip into the inner Solar System gives them additional gravitational perturbations, causing them to either fly into the Sun or gain enough kinetic energy to escape entirely. This latter fate is the case for Comet Catalina, which reaches perihelion on November 15th and then heads out of the Solar System after putting on one final show for observers on Earth.
good riddance!
Slashdot, fix the reply notifications... You won't get away with it...
The summary leaves out the most important part of this whole thing, the part that is most critical to answer: what kind of shirt was the spokesman wearing when he made the announcement? We can't possibly evaluate if this is OK unless we know. Is there any word?
Shutting down free speech with violence isn't fighting fascism. It IS fascism!
It's a chaotic system. The odds of the gravitational perturbation increasing the speed of the comet (and by extension, pushing it away and increasing its period) aren't much different than the odds of the perturbation decreasing it. And the effect is small, that a given orbit might bring a comet that has near escape velocity over the edge (as apparently is happening here) but Halley's Comet has nowhere near that.
We have been informed that Catalina's Comet is the home of a major warez site. We recommend that you get over to it immediately to sort it out. We'll keep a slot open for you on the comet's return.
Why doesn't this happen to Halley's Comet? It gets perturbed by the gravity from the gas giants, yet has managed to retain a period of 74-79 years since 240 BC. That's a lot of trips through the solar system. Because it's a short period comet, it spends more time around the gas giants than a long period comet. That should subject it to more gravitational perturbations, but it's still remained very periodic. Why is that?
Luck, mostly. An object will either be expelled or gravitationally (tidally) torn apart by the sun after a few trips around the solar system, with an exponential distribution describing how many trips it makes. As with all exponential distributions, the curve flattens out to the right, and if any particular object has just the right orbital parameters to make i.e. 10 or 20 or 50 passes, then it's pretty much fallen (by luck) into the sweet spot of orbital resonances to keep making more passes. The chances are astronomically low that any particular object will have this luck, but there is a huge number of objects out there, so some do beat the odds.
Halley's comet is simply one of the few that beat the odds.
It is dangerous to be right when the government is wrong.
Psh, everyone knows fantasy football is "skill based" ;-)
We'd have to grab it or land on it...which means we'd have to match its speed...which means we'd be going fast enough to do this anyway, so why bother grabbing a comet?
This makes Newtonian sense, however I can think of one scenario where we don't need speed up to the comet. Place the spacecraft on its path. Basically instead of trying to catch the comet, we let the comet catch up with us. Not recommended for humans or delicate equipment.
You forgot to say "SJW".
I do not want your cheap brainburning drugs. They are useless for work. And I am a working man today.
Anyone else find this declaration in the article mildly annoying?
Out a little farther, the four gas giants -- themselves failed stars --
At best, one would think that of the four, only Jupiter could even remotely be considered a failed star. I would think the other three don't have nearly enough mass to qualify for such a designation.
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