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Brett-NZ
2003-Jul-03, 05:15 AM
In the movie, was the rotation of the Earth itself reversed? The reason I'm asking this is that I think that in the last shot, just as the end-credits began, the Earth was rotating backwards. I know that it shouldn't have had a visible rotation but I think it was a shot over Africa (daylit) and Madagascar was emerging from the terminator.
Is there anyone here able to confirm or deny this.

Karthesios
2003-Jul-03, 07:22 AM
Yup, Earth was going in reverse...

tracer
2003-Jul-03, 04:00 PM
Maybe it was a side effect of having nuked the core to get it spinning again. :roll:

Spare Time Continuum
2003-Jul-24, 12:11 PM
You thought the apostrophe mistake was bad? Get this - The acronym "DESTINI", whose "INI"-ending they explained during the movie, was later spelled "DESTINY" as the "location" subtitle.
Why not "DENSITY", or just "DENTISTRY" for that matter?

I also spotted the "super-dense man" inaccuracy straight away, but here is a nice juicy one that I didn't see in Phil's write-up:

The hero pulls the heavy fuel rods out of the Virgil's engine to use for the nukes, and he struggles with their immense weight.
BAD: Now I've never been to the centre of a planet myself, but it seems to me that the effective gravity at the centre of the earth would be more or less zero - the attraction to the earth's mass is coming from all directions around (above) you, in roughly equal magnitudes, thus cancelling out. Right? (Wrong?)
Sure, they weren't QUITE at the centre of the earth, but still...
[-X

kilopi
2003-Jul-24, 02:04 PM
The hero pulls the heavy fuel rods out of the Virgil's engine to use for the nukes, and he struggles with their immense weight.
BAD: Now I've never been to the centre of a planet myself, but it seems to me that the effective gravity at the centre of the earth would be more or less zero - the attraction to the earth's mass is coming from all directions around (above) you, in roughly equal magnitudes, thus cancelling out. Right? (Wrong?)
Sure, they weren't QUITE at the centre of the earth, but still...

We talked about this before (http://www.badastronomy.com/phpBB/viewtopic.php?p=73114#73114). The force of gravity stays about constant all the way down to the core-mantle boundary, about halfway to the center of the Earth. However, some people have said that the characters in The Core actually do go to the very center of the Earth. I'm still waiting on a clarification (I haven't rented the DVD yet :) )

tracer
2003-Jul-25, 12:49 AM
The force of gravity stays about constant all the way down to the core-mantle boundary, about halfway to the center of the Earth. However, some people have said that the characters in The Core actually do go to the very center of the Earth. I'm still waiting on a clarification (I haven't rented the DVD yet :) )
I watched the movie twice when it was in the theaters, and this was one of the things I paid careful attention to the second time.

The Virgil does not travel all the way to the center. However, it does travel deeper than the core-mantle boundary. They travel down until they are just a hair's breadth above the outer-core/inner-core boundary.

When I did the calculations (early on in the thread page you linked to), I came up with a figure of 0.4 times the Earth's surface gravity as the gravitational force they should be experiencing at this depth, assuming current real-life estimates of the inner core's density are correct. (However, this may not be a viable assumption. In the movie, they discover that the outer core is less dense than previously thought, which might mean that the inner core is more dense than previously thought since we base our calculations of its density, in part, on the total mass of the outer and inner cores combined. In fact, in that other thread, I calculated that if the outer core's density were only half the currently estimated value, the inner core would be so dense that the surface gravity when you're right on top of it would be 2.8 times the surface gravity of the Earth!)

kilopi
2003-Jul-25, 01:32 AM
There ya go. Thanks tracer, I'd forgotten those calculations.

Sorry, Brett-NZ, it looks like the script writers had it covered. :)

Spare Time Continuum
2003-Jul-25, 05:49 AM
Thanks! I was actually wondering about that.

Christian
2003-Jul-25, 09:12 AM
Yep, those Hollywood scriptwriters just can't ever be too careful when it comes to science. 8-[
Maybe the earth going backwards was a prank by the computer animators. Probably nobody else noticed.

kilopi
2003-Jul-25, 09:22 AM
Oops, I should have addressed my remark to Spare Time Continuum rather than Brett-NZ. Apologies.

tracer
2003-Jul-25, 07:21 PM
In the movie, they discover that the outer core is less dense than previously thought, which might mean that the inner core is more dense than previously thought since we base our calculations of its density, in part, on the total mass of the outer and inner cores combined. In fact, in that other thread, I calculated that if the outer core's density were only half the currently estimated value, the inner core would be so dense that the surface gravity when you're right on top of it would be 2.8 times the surface gravity of the Earth!)
Fun fact: If this were the case, the inner core's density would be 6.8 times its currently estimated value -- which would make it about 88 grams per cubic centimeter.

This is over 7-and-a-half times the density of solid lead.