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."

Comments

Shocking!

[Black Parrot]

As someone on Usenet already put it, seeing how the Electric Universe proponents rationalize the failure of their predictions may be more interesting than seeing what the mission discovers.

That's slick

[Rosco P. Coltrane]

expelling material at supersonic speed

Supersonic speed in hard vaccuum? interesting...

Re:BS?

[MustardMan]

As a followup to my previous post, I've done some more googling. I found one of the biggest proponents of this wackjob theory happens to be one Jim McCanney, whose other claims include such gems as "weather is being manipulated". For a good thorough debunking of this crackpot, you might want to check out one of my favorite sites, Bad Astronomy.

The best part about the internet is, it's given everyone a voice.

The worst part about the internet is, it's given people like this a voice.

It is interesting actually

[p3d0]

Someone says this any time the term "supersonic" comes up in connection with outer space. This Electric Universe theory might have a lot of things to criticize, but the notion of supersonic speeds in space isn't one of them. See bow shock and termination shock for instance.

Interplanetanetary space (even interstellar space) is nowhere near a "hard vacuum".

what a bunch of hooey

[LMCBoy]

Yeah, interesting theory. Too bad no one has ever taken a spectrum of a comet tail to find out if it's sublimated ices or 'supersonic' bits of rock.

How does their 'theory' purport to explain the second tail of comets, which points along the comet's direction of motion, rather than away from the Sun? Maybe only *some* of the bits of rock are electrically charged? Maybe magic comet elves rub the charge off of some bits?

I had never heard of the Electric Universe, but they seem on par with the flat-earthers and creationists.

Re:BS?

[Peter_Pork]

The best part about the internet is, it's given everyone a voice. The worst part about the internet is, it's given people like this a voice.

But, it takes 5 minutes of googling to find the problems with these alternative theories. In a sense, the Internet is the ultimate dream of peer reviewing, which is the foundation of modern science.

Re:We finally fight back against comets and astero

[myowntrueself]

"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."

Well spotted; scientific theories *must* be disprovable.

It must be possible, in principle, to disprove a theory otherwise its an axiom. And axioms need some justification (like Newtons laws of motion which are not scientific theories but (justifiable) axioms).