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First Results From Deep Impact Mission
jdoire wrote to mention a Physicsweb piece revealing some of the first bits of data from the Deep Impact mission. From the article: "Based on data from the flyby spacecraft and the impactor, Michael O'Hearn of the University of Maryland and colleagues say that Tempel 1 belongs to the Jupiter family of comets, although its overall shape and surface features are quite different from the nuclei of the two other comets that have been studied in detail -- Wild 2 and Borelly. They also report that Tempel 1 consists largely of extremely fine particles that seem to be very loosely bound together: in other words, the comet is more like a pile of powder than a solid rock." Looks like the Electric Universe folks were a bit off.
If the're "loosely bound together" how is that there were an impact at all? Wouldn't the probe just sunk into the comet?
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and their advertising application masquerading as a "website"
http://www.nasa.gov/mission_pages/deepimpact/medi
Well dang, if that's all it is, c'mon in for a landing buddy. Man, we had you comets all wrong.
Won't be a planet killer...more like a planet tickler...cute little fella.
There's nothing Intelligent about Intelligent Design.
I think its cool that we are all ready at the point where we can crash probes into comets and examine them. I wonder how long it will be until we can actually pull a comet into earth orbit and mine it for resources.
The comet seems to have survived:i media/addscolor90605.htmli media/1118923Fig7-90605.html
http://www.nasa.gov/mission_pages/deepimpact/mult
http://www.nasa.gov/mission_pages/deepimpact/mult
Procrastination -- because good things come to those who wait.
10101110
Does this mean that using an significantly large explosive device is almost a feasible scenario for specific types of comets.
I mean, I can understand not using that approach for something make of rock and ice, but with fine particles one would think that sufficient force would break it apart like a cue ball.
Obiviously this is just fuzzy thinking, but does anyone have any scientific input to why this would or would not be an emergency solution to be put on the table for this specfic type of comet?
I once saw a documentary about a comet that was made completely from garbage. It was nearly impossible to destroy because it was such a loose collection of items. This comet seems very similar.
Ninjas don't carry tic tacs
How does it feel to be potential parents to an alien species?
Like a Scientologist?
(rimshot!)
"Rocky Rococo, at your cervix!"
The gravity and velocity of the comet i'm sure held it together. Your used to being on Earth, rules are a bit different when you leave the atmosphere. Matter tends to clump together, when that matter is in an orbit and moving at high velocities all together, it acts nearly as a solid. Despite that its a bunch of powder, you still calculate its center of gravity as though its solid. You are a bunch of cells but if I hit you, you don't fall apart. A bunch of powder moving in a direction will continue to move in that direction until acted upon by an outside force. The comet was big, the probe was small, the force not nearly large enough to knock it off oribt or to make the thing explode.
Regards,
Steve
http://en.wikipedia.org/wiki/Tunguska_event
e nt_040812.html
There have been a wide range of theories about this, but a puffball comet explains a lot about what happened there. From Aliens;
http://www.space.com/scienceastronomy/tunguska_ev
to Victorian Era Superweapons testing ala League of Extraordinary Gentlemen (the Comic book, not the movie). I have tried to find the site on Google Earth but have not been lucky.
Sorry about the writing. Robot fingers, you know? Cliff Steele in DOOM PATROL #23
We make dumb posts that over-simplify and generalize events. This is great commentary.
If you don't have anything worthwhile to post, don't post at all. I know you're just a silly troll, but a lot science has been at the hest of speeding things up and mashing them together to create collisions. Ever heard of a particle accelerator?
Hard to believe that Neil Armstrong was not familiar with Lunar Surveyor. See http://nssdc.gsfc.nasa.gov/planetary/lunar/survey
John Sauter (J_Sauter@Empire.Net)
The military is currently researching railgun technology. The shells said railgun will fire are inert and will not explode in the same manner as conventional shells. They'll simply strike the unfortunate target with such force that it'll basically explode. Nasa did the same thing, just with more mass and more velocity, no chemical reaction could explode with the same force obtained by striking a target in this manner.
"Exactly what was in that impactor that could create a city-sized crater?"
It is exactly the inordinate size of the crater that has caused them to beleive that the surface is like a 'pile of powder'. It wasn't that the impactor was so large or going so fast relative to the target, it was that the surface material reacted so violently in relation to the physical impact. That denotes that the surface material has little to no cohesive nature. What really makes that curious is why would it possibly stay together to begin with then? It is a relatively small body and should exhibit a very very small gravitation influence. Why would such material form a body that at least gives the illusion of cohesion in the abcense of the physics that we believe it takes create such a body?
I can't think up a good answer beyond the usual origins of life or origins of the solar system stuff. It's not really practical for the layman, but it's interesting to scientists. I hold to the idea that the pursuit of knowledge in and of itself is a noble pursuit.
On the other hand, I do hear quite often "why should I care?" from laymen. Well, turn back 100 years to the beginnings of quantum theory. "Why should I care how electrons behave around protons" or "Why should I care that uranium undergoes fission when bombarded by neutrons?" The first led to the development of the transistor and electronics and computers and just about everything technological in the past 50 years. The second led to the development of nuclear power (and weapons) and has also had a tremendous impact. By the same token "Why should I care what comets are made of?" may not have an answer now, but it might in the future. To withold funding from one scientific project may prevent some new discovery or technological advance. If all scientific endeavours were left to private industry, sure we'd make advances, but most private research is focused on the near term whereas public research is knowledge for knowledge's sake, and often produces advances and breakthroughs not seen in private research. In NASA's case, their investment in the 50's and 60's led to quite a few developments such as communication satellites and paved the way for businesses like Scaled Composites. That's at least worth something. I know I'm proselytizing a bit, but I think I have at least some of a point.