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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."
> If the internal makeup of this comet does represent the compounds present at the start of the solar system, there could be some serious head scratching and changing of theories going on if amino acids are found, let alone any more complex organic compounds like RNA/DNA, however unlikely.
We already know that amino acids are present in deep space. Slightly more complex molecules too, IIRC.
Of course, that just means they're relatively easy to form by non-biological processes, so it doesn't necessarily follow that they originated on earth by falling from space.
Sheesh, evil *and* a jerk. -- Jade
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.
Yes, it's just that the news last night said "about 5 kilotonnes", so does that mean that the 4GJ figure is wrong or was the news...Actually why don't we just calculate it:
.5*372Kg*(37000Km/hr=10000m/s)^2 -> 18.6GJ.
So, the news was wrong. Fair enough.
TWW
"Encyclopedia" is to "Wikipedia" what "Library" is to "Some people at a bus stop"
> With all that outgassing, you would think a comet's surface would be a lot more sharp -- full of crevasses and ridges (like it was on Deep Impact) But this one seemed almost smooth, like an asteroid.
Some of the final picture before impact showed what looked like big chunks, perhaps glued together by snow.
I wonder whether the outgassing weakens it enough to "melt" to a new configuration each time it passes the sun.
Sheesh, evil *and* a jerk. -- Jade
Please note that the impactor contained electronics and stuff to manoeuver.
The sibling post of this one, which says the object needs to be in orbit in order to be a satellite, gives the correct definition of a satellite.
A block of copper can thus be a satellite, but the impactor was clearly not orbiting the comet.
You see?
--- Sigmentation Fault - Comments Dumped
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.
Somebody give this an underrated mod point. This isn't a troll and doesn't deserve a -1.
I don't agree with the poster's opinion, but it shouldn't be modded down just because you don't agree with it.
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?
[b.belong('us') for b in bases if b.owner() == 'you']
No.
Ignoring the fact that this was supremly cheap, that the money would not have funded a season of "Extreme makeover home edition." Much less solved genocide or starvation.
Ignoring the fact that this provided important scientific information about the formation of the solar system. Yeah, ignore that.
_WHERE DO YOU THINK THEY SPENT THE MONEY?_
This is your tax dollars going to continue to fund the lives of thousands of american citizens, businesses large and small.
All this technology over there and the big media (like CNN) have to display a picture captured from video of a picture of a projection screen picture of some geeks desktop as the main event picture. WTF?
Then we get other pictures that have a large black border around them so they are so small they are not worth even looking at.
Can't you guys have a computer there with a decent video output card in it that connects to the JPL internal network and a ftp server that contains pictures as they come in?
I mean, how hard can it be to have a ftp server set up that *automatically* (via a shell or perl script) processes the pictures as they are received and places them on a ftp server, maybe one that even us people who paid for the mission can access.
I am still waiting today for some good pictures, all there is this morning are low res pictures.
Can't these rocket science people figure out how to write a perl script that processes those pictures to make a better quality in a automatic and quick way?
I appreciate all your work, but it's really frustrating at this end knowing how to program and having high speed access, but yet not able to get any good raw data.
How about a UDP broadcast stream we can all tap into and get the raw data ourselves and decode it ourselves via open source software? You think we couldn't understand your specs on the data format? Just give it to us, include sample test data. I can process data as good as your guys there, just give me some specs.
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 :-)
It does.
Weaselmancer
rediculous.
From the original post: "Initially thought to be shaped like a pickle, it came to resemble more of a banana shape as comet Tempel I drew closer." For four seasons I hosted Inside Space, a science fact program on the SciFi Channel (it's like being on the Celibacy Show on Playboy). We traveled everywhere visiting the brightest minds in space (pun intended) and nearly every human on the Earth who has "rocket scientist" on his/her business card. There was one recurring theme. Everything in space that's not a planet or star is potato shaped - period, case closed. Next.
The suggestion that the mother ship do a 29,000 mph velocity change and match the trajectory of the comet to continue observing it is such a contrast with the other, reasonable suggestions that I took it for a troll at first. It is just so patently foolish that he MUST be trying to get a reaction. But looking at jmichalg's other posts I see no clear evidence of other trollery. Oh he likes to argue but is it a troll?
So which is it? Are you ignorant or obnoxious?
Don't moderate flamebait as Troll. Know the difference or you will be Meta-moderated.