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Cometary Fireworks Go Off Without Hitch
PingXao writes "The JPL Deep Impact mission has successfully slammed a sattelite into Tempel 1 at 23,000 mph. (37,000 kph). The autonomous navigation system was primed for up to 3 course corrections in the final 2 hours of flight but only had to execute two of them. The second was so small - expending less than a pound of propellant - that impact would have occurred without it. Initially thought to be shaped like a pickle, it came to resemble more of a banana shape as comet Tempel I drew closer. Impact was estimated to have released 19 Gigajoules of energy, or the equivalent of 4.5 tons of TNT."
This is quite likely the finest result Nasa has had for a long time. To quote a professor who was quite surprised by the event :
"It was like mosquito hitting a 747. What we've found is that the mosquito didn't splat on the surface, it's actually gone through the windscreen."
The photos too, are quite amazing. A huge amount of stellar dust, ice, and rock exploded out of Tempel 1's surface. All from the impact of a probe just the size of a washing machine.
Over the following few days, the second module of the mission will further analyse the materials ejected from the comet, and it is believed scientists will discover much about the creation of the universe (some of the material hasn't been disturbed in over 4 billion years) and the composition of comets in general over the next few months as they complete their analysis of this great event.
This is a gif animation of the impact as observed from the Lowell Observatory.
There's a handy tool for doing that kind of calculations, called 'units'.
A marsbar (65g) has about 294 kilocalories (source: http://www.weightlossresources.co.uk/calories/calo rie_counter/chocolate_sweets.htm)
So, we edit /usr/share/misc/units.dat (may wary depending on distro) to add the line:
marsbar 294 kilocalorieWe then launch units:
%units2085 units, 71 prefixes, 32 nonlinear units
You have: 19 gigajoules
You want: marsbars
* 15435.619
/ 6.4785221e-05
You have:
So apparently, 19 gigajoules of energy equals ~15436 mars bars.
Seems the electrical universe people haven't had time to update their website about their prediction about the results. IIRC, they were saying that the results would be much less spectacular than predicted, and yet a few hours ago I heard some of the NASA people expressing surprise because the impact released a lot more material than most of them expected. The electric universe proponents also seemed to think that the impactor electrical systems would fail before it reached the comet (because of "megalightning" and all that), while they seem to have have lasted right up until the impact.
So....will they do the right thing and modify their theory to fit the observations, or will we be treated to a lot of hand-wringing about how the theory actually predicted this result (but us non-electrodynamical people just don't understand the theory and its implications)?
And will /. post a follow-up article about the electric universe proponents' reaction to the results, or is that not news for nerds?
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You mean the Rosetta mission?
Currently en route to a close rendezvous with comet Churyumov-Gerasimenko, to be followed by releasing a lander (which will use a harpoon to cling to the surface). It was in a position to make distant observations of comet Tempel for the current fireworks show.
It won't do what you describe but will instead take a roundabout route that will allow it to basically sneak up on the comet.
Oh, and it's European, not American :-)