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Swing and a miss
March 9, 2012 at 5:52 am
Earth is due for an extremely close enounter early next year, with the recently-discovered Asteroid 2012 DA 14. Here's a simulation based on the available data showing how it will play out:
http://www.youtube.com/watch?feature=pla...7YTmS6U8WM
This is simply stunning. Astronomers have only known of this tiny rock's existence for a few weeks and already enough is known about its orbital motion to make predictions of such incredible accuracy. Sod all those bible/kerrang codes, horoscopes and goat entrails or whatever; I know which side my money's on.
(H-T Phil "Bad Astronomer" Plait)
At the age of five, Skagra decided emphatically that God did not exist. This revelation tends to make most people in the universe who have it react in one of two ways - with relief or with despair. Only Skagra responded to it by thinking, 'Wait a second. That means there's a situation vacant.'
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RE: Swing and a miss
March 9, 2012 at 5:59 am
Wooooeeeeee. That is a bit close, cosmologically speaking.
How long until the first claims science is wrong and rapture is incoming after all. He just hit snooze on his salvation alarm clock when he realised nobody was coming.
Very interesting, It didn't mention how long until it passes again, just that its next past is too hard to predict at the moment.
Self-authenticating private evidence is useless, because it is indistinguishable from the illusion of it. ― Kel, Kelosophy Blog
If you’re going to watch tele, you should watch Scooby Doo. That show was so cool because every time there’s a church with a ghoul, or a ghost in a school. They looked beneath the mask and what was inside?
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RE: Swing and a miss
March 9, 2012 at 6:20 am
(This post was last modified: March 9, 2012 at 6:21 am by Cyberman.)
Yeah, it'll be a test of our faith or another Abraham and Isaac style bait 'n' switch. Maybe it'll turn out to be demonstration of infinite mercy: this god could wipe us out anytime it wants to, it just chose not to this time. Next time though, hooboy! Asbestos trousers all round!
We - i.e. proper astronomers - won't be able to predict how the encounter will change the game, since the calculations are based on data that can't be known until the event happens. So until then we just can't know what a future encounter will look like or when it could occur; "No man knoweth the hour" and all that cobblers. It's even possible, though probably not very likely, that it could hit us next time.
Incidentally, there was a huge fireball seen over the UK earlier in the week, though I missed it myself. Now I'm starting to wonder if there might be some connection, perhaps an associated piece of debris or similar.
At the age of five, Skagra decided emphatically that God did not exist. This revelation tends to make most people in the universe who have it react in one of two ways - with relief or with despair. Only Skagra responded to it by thinking, 'Wait a second. That means there's a situation vacant.'
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RE: Swing and a miss
March 9, 2012 at 6:52 am
I missed it as well, which was intensely frustrating. Would have been an interesting phenomena to see.
One thing I never quite understood, and if you're an astronomer, maybe you could explain it.
The course of this asteroid will be seriously affected by the earths gravitational pull, however, considering the distances involved in its "orbit", surely even a small pull would send it in a vastly different distance, rather than a mere 22,000 miles that would make it dangerous on another pass.
Does its course get readjusted somehow during its orbit by other gravitational forces, or is the gravitational effect far lower than the graphics would indicate?
Self-authenticating private evidence is useless, because it is indistinguishable from the illusion of it. ― Kel, Kelosophy Blog
If you’re going to watch tele, you should watch Scooby Doo. That show was so cool because every time there’s a church with a ghoul, or a ghost in a school. They looked beneath the mask and what was inside?
The f**king janitor or the dude who runs the waterslide. Throughout history every mystery. Ever solved has turned out to be. Not Magic. ― Tim Minchin, Storm
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RE: Swing and a miss
March 9, 2012 at 6:57 am
meh  we get these ALL the time.
"The Universe is run by the complex interweaving of three elements: energy, matter, and enlightened self-interest." G'Kar-B5
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RE: Swing and a miss
March 9, 2012 at 7:00 am
(March 9, 2012 at 6:57 am)KichigaiNeko Wrote: meh we get these ALL the time.
Its still interesting thou. I love this kind of thing  I wish I'd dedicated myself to astrophysics instead of computer science as a teenager.
Self-authenticating private evidence is useless, because it is indistinguishable from the illusion of it. ― Kel, Kelosophy Blog
If you’re going to watch tele, you should watch Scooby Doo. That show was so cool because every time there’s a church with a ghoul, or a ghost in a school. They looked beneath the mask and what was inside?
The f**king janitor or the dude who runs the waterslide. Throughout history every mystery. Ever solved has turned out to be. Not Magic. ― Tim Minchin, Storm
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RE: Swing and a miss
March 9, 2012 at 7:55 am
(March 9, 2012 at 6:52 am)NoMoreFaith Wrote: One thing I never quite understood, and if you're an astronomer, maybe you could explain it.
The course of this asteroid will be seriously affected by the earths gravitational pull, however, considering the distances involved in its "orbit", surely even a small pull would send it in a vastly different distance, rather than a mere 22,000 miles that would make it dangerous on another pass.
Does its course get readjusted somehow during its orbit by other gravitational forces, or is the gravitational effect far lower than the graphics would indicate?
Everything you said is correct. DA 14's orbit is going to get quite a kick next year and it will be interesting to see where it goes. It will certainly get a huge speed boost, altering its trajectory even more (it's basically a natural version of the slingshot encounter trajectories that NASA uses to boost their spacecraft, though they know beforehand what the result will be - there'd be no point otherwise). Basically orbital mechanics is a tangled mass of competing gravities.
The graphics in the simulation are quite accurate up until the moment of the close encounter. From that point on, the game changes in unpredictable ways based on DA 14's speed, mass and angle of encounter. Imagine a weird kind of golf course with the hole (Earth) down in a gentle crater-like hollow (Earth's gravity well). By hitting the ball towards the rim, it's possible to slingshot around the hollow and alter its course. Varying how hard you hit it and the angle you aim it, the ball can be sent in any direction and speed. Worst case, you hit the Earth; best case, the ball whizzes off out of the course altogether.
Now imagine our golf course has other hollows of varying size, further out from the Earth one. That'll be the other planets, most notably Jupiter. As long as they are in the right place at the right time, they muddy the picture even more, bearing in mind that gravity falls off proportional to the distance between two objects such that the asteroid will be affected more by a closer planet than one further out.
This golf course analogy is not a totally perfect one but hopefully it illustrates the basics of orbital mechanics. I'm not a professional astronomer and I look at a board filled with calculations with almost the same level of comprehension that a dog would. But I do have something of a grasp of what happens even if I make it sound really confusing.
(March 9, 2012 at 6:57 am)KichigaiNeko Wrote: meh we get these ALL the time.
But rarely as close as this. It's like having a car missing your foot by the width of a gnat's cock.
At the age of five, Skagra decided emphatically that God did not exist. This revelation tends to make most people in the universe who have it react in one of two ways - with relief or with despair. Only Skagra responded to it by thinking, 'Wait a second. That means there's a situation vacant.'
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