My rant for this month.. Asteroid hitting the earth renderings

[Oneslowz28]

Ok so I am watching the show on PBS called 400 years of the Telescope. They just showed a rendering of an asteroid hitting the earth. Upon impact into the pacific ocean it showed the earth beginning to incinerate. The other week on Nova they had a similar animation. I also remember several other shows on various "knowledge" networks where they showed the earth getting hit by an asteroid and the resulting earth incineration immediately following.

My rant starts here: Every one of these shows spoke of how off Hollywood's take on this. I just think its odd that if an asteroid were to hit the earth in the center of any large ocean that it would generate enough heat to flash boil the entire ocean and allow the underlying earth to incinerate. I mean if these scientist want to promote the truth then why render an animation where something that is physically impossible and pass it off as the truth?

[DaveW]

I mean if these scientist want to promote the truth then why render an animation where something that is physically impossible and pass it off as the truth?

Honest answer? Most scientists work in facts, figures, and graphs. Animations like that are made when they need to explain something to non-scientists. They pull viewers in on TV shows and have a greater impact on the target audience.

Effectively, it's the 'rule of cool'. Factual graph vs. cool animation of the earth being blasted? It's pretty clear what will win in a TV show. It's just important to keep that in mind. Everyone has an agenda; for 'educational' TV shows, it's to make money.

-Dave

[Oneslowz28]

I understand that. Its just when I see things like that I get a little perturbed.

[mtekk]

The short answer:
Theoretically, if a sufficiently large asteroid collided with an ocean, in particular the Pacific, the impact could cause a quite massive release of methane, which could cause quite a violent explosion.

The slightly longer answer:
There are massive amounts of methane trapped at the ocean floor in a hydrate form. Recently, several companies are trying to commercially recover the methane trapped in this state as it is "abundant" below a certain depth. Supposedly, it is quite sensitive to external disturbances and will break down quite easily, releasing the methane. If the impact can cause water to boil, it could be able to cause the released methane to combust.

[Drum Thumper]

http://blog.drumthumper.net/wp-content/uploads/2008/10/unp1lw5-259x300.jpg

[mtekk]

http://blog.drumthumper.net/wp-content/uploads/2008/10/unp1lw5-259x300.jpg

Talk about entry and exit :D.

[OvRiDe]

I think that in most cases they are referring to the fact that the heat blast from the collision could be enough to actually ignite the atmosphere. At that point it would be hot enough to pretty much incinerate everything in its path.

[.Maleficus.]

http://img12.imageshack.us/img12/3641/1236090210351yx1.jpg


In all seriousness though, Dave pretty much answered it straight on.

[Oneslowz28]

http://blog.drumthumper.net/wp-content/uploads/2008/10/unp1lw5-259x300.jpg

That's what happens to me when I eat Taco Bell for lunch or A sausage biscuit from McDonald's for breakfast.