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Deep Impact on Comet Theory
AlexGP writes "Proponents of the Electric Universe theory have gone out on a limb ahead of Deep Impact. They're predicting it will show comets are just rocks and not dirty snowballs.
Controversially they assert comets are highly negatively-charged asteroids on eccentric orbits. As they travel further into the Sun's radial positive electric field, they discharge into space, expelling material at supersonic speed."
The article looked like crackpot stuff to me, but what clinched it was this from the linked article on megalightning:
Yeah, sure NASA has more authority than the First Amendment. Bet these crackpots buy their tinfoil in bulk.--
I don't want to rule the world... I just want to be in charge of mayonnaise.
Finally, we get to extract vengeance upon the comets for killing off our dinosaur cousins. Comets gotta learn that for every action there's a reaction. Halley, you're next! And to all the planets out there .. you're either with us or against us.
..their theory is interesting .. I dont think they are whacko ..science thrives because of diversity in thought .. However, if you read their predictions, nothing short of a massive water splash of water folllowed be an ice tsunami on the asteroid would cause them to change their mind. I wish they'd put some numbers (if the crater is larger than "100 feet" then we are wrong. "If the ice detected in the debris is greater than X percent, we are wrong" etc.
.. if they genuinely wish to be taken seriously they should find out the sensitivit of the instruments (publicly available) and make solid predictions.
Anyway, about Electric universe folks
Non of that is done
Electric universe isn't the only interesting group out there. Some claim that comets are made of antimatter. If so the Tempel 1 collision should be a whopper. On the otherhand the lack of hard evidence (or hard radiation) coming from comets makes this theory a bit improbable. If comets were antimatter, I suspect we would have noticed the 0.51 and 938 MeV gamma rays produced when particles in the solar wind struck the comet.
Two wrongs don't make a right, but three lefts do.
> More info on the "Electric Universe" topic:
Jokes aside (and you gotta admit this story is jokebait), Google Groups will show you what it's all about. Don't know why Taco linked the term to a JPL site.
Sheesh, evil *and* a jerk. -- Jade
Space isn't a perfect vacuum. Sound waves and shocks can exist anywhere there's enough gas to act in an ordered, collective fashion, and on solar system scales that doesn't require a very high density.
The solar wind is supersonic--it travels faster than sound waves will travel in it (which is why there's a bow shock upstream of the Earth). In the case of a comet, as you quoted, it's expelling material, and sound waves can travel in that.
Somebody makes a crack like this every time a space fluids topic gets posted on slash.
(Incidentally, why the heck is this posted under "Science" instead of "It's Funny, Laugh"? These are absolute crackpots.)
Space vacuum is not 100% particle-free, so there IS a speed of sound.
For example, "supersonic" solar wind creates shock waves when it meets interstellar space (Wikipedia has some nice pictures about it: http://en.wikipedia.org/wiki/Heliopause).
Of course, you won't hear anything in space using conventional microphones, but because most of particles in space are ionized we can watch these effects from Earth using radio telescopes.
From what little I know, the so-called "Electric Universe" theory (or theories) is a variant on Plasma Cosmology [wikipedia.org]. Plasma Cosmology is a fringe scientific theory that asserts that plasma physics should play a more prominent role in cosmology and that the electromagnetic force should be considered more important than gravity in the evolution of the universe. This idea apparently originated with Nobel Prize winner Hannes Alfvén.
Of course, even Nobel Prize winners make mistakes (or at least the one I know does :-) ). Plasma Cosmology is almost uniformly viewed as incorrect and irrelevant by physicists and astronomers. The reasons, as far as I can tell, are that standard cosmology has been quite successful in predicting things like the cosmic microwave background and elemental abundances, not to mention things like cosmological redshift. Plasma cosmology cannot reproduce these things without adding on a lot of convoluted features that rely on some unproven (and seemingly outlandish) new plasma physics that has never been seen on Earth. In short, Plasma Cosmology doesn't explain a lot observations correctly in a simple way. It hasn't proven itself useful, which in the end is the measure of a good scientific theory.
So the short answer is, "Yes, it's BS". Now cue the die hard supporters claiming there's some sort of conspiracy to cover-up their theory, which is pretty silly if you know how science really works.
"You call it a new way of thinking; I call it regression to ignorance!" -- Operation Ivy
Sort of like how Titan didnt answer whther there are really methane lakes currently on the surface or not.
It showed there aren't large methane seas, which was one theory.
And like how the Mars probes havent told us if there is/was life.
That wasn't the point of Spirit and Opportunity. That was the point of Beagle, unfortunately.
In fact whether there was water is still disputed.
Not really. The discovery of hematite by the Mars Rovers is pretty conclusive. Combine that with the satellite studies that have shown water combined with CO2 in the ice caps, and there is no real dispute at all.
We need to be sending better probes out there that can do some real science.
They are doing real science. Science doesn't provide yes/no answers. It is about gathering data and doing experiments. We are doing more of that now than ever.
Space probes havent advanced in decades.
Considering the amazing Spirit and Opportunity missions and the pictures coming back from Cassini/Huygens as compared with brief visits to the outer planets from Voyager, I find that an very odd statement.
NASA did take the camera and the film, I remember reading about it when it happened. It is probably googleable and I believe it was discussed on slashdot before during that time frame. Haven't kept up with it though so don't know what they did with it.
No, seriously? Is there really not enough happening in the world this morning that you have to give 5 minutes of fame to a BUNCH OF RETARDED IDIOTS who's claims are obviously bunk if you think about it for 2 seconds.
And people actually subscribe - pay money to this website - when it has shit like this for an article?
You claim that Plasma Cosmology does not predict as well as standard cosmology. This is exactly what Plasma Cosmology promponents say in reverse, and it's meaningless without examples and data. You mentioned three examples.
The evidence that I have seen is that standard cosmology did not accurately predict the microwave background level, but predicted wrong several times and then adjusted to "predict" it after its level was measured. It did not "predict" elemental abundances either, rather someone found a way to work it out so that if you started with something you'd end up where we are now. That doesn't prove the thoeory, it just shows that it can be made to fit. That is only one part of a good theory. Finally, the well-known redshift/distance correlation was measured long before the standard theory was developed, so that again is not something that standard cosmology "predicts."
Both theories have solid ways to explain known observations, and both can point to things that they explain better or more simply than the alternative. I don't think it's fair to discount Plasma Cosmology as a fringe theory based on its merits. It is fringe only because people like you treat it as such instead of honestly trying to evaluate which parts of its theory may be accurate.
(On topic, this comet theory is bunk. I believe in spectroscopy, which proves that comets have lots of ice. Off topic again, I also believe that the big bang is a theory in need of replacement and that the redshift/distance correlation is not just about doppler shift, but that's just me)