Prettying f’ing cool regardless
Definitely fake. But, agreed, it is well done and cool-looking.
I think it’s from a commercial. I haven’t seen that particular one, but there’s another commercial I’ve seen several times for a pickup truck (don’t recall the manufacturer - Ford maybe?) that follows the same format. It’s set in the desert and shows a nuclear explosion going off. After a moment debris (including a truck) starts hitting the ground around the camera. After a few seconds the truck starts up and drives away. I don 't recall if the driver gets in, or we’re to assume he was in it during the explosion, flight and ground impact.
IOW, the point of the commercial is, "Our truck is so well built, you can blow it up with an atomic bomb (or hit it with a giant meteor) and it’ll be unscathed.
It’s a volcano, not a nuclear explosion. It’s an ad for the Ford Explorer SUV.
Ok, I think it’s fake but is there anything in the video that proves it’s fake?
Yes. The object is moving too slow to create such a fireball on impact ( I estimate its apparent speed at around 500-600 MPH); meteors don’t leave thick, black smoke trails; and by the time it’s gotten to the thicker layers of the atmosphere, objects that size are no longer moving fast enough for compressive heating anyway. Additionally, due to the low angle of incidence, there should have been considerable material ejected towards the camera in the direction of travel, but there wasn’t. All the material was apprently ejected upwards.
You mean besides the fact that the truck was undamaged after being hit by a meteor the size of a house?
It looked to be somewhat smaller than the truck itself. Scale is a bit hard to judge, but I don’t think it was meant to be anywhere near house-sized. I think much of what you see before the object “hits” is supposed to be an envelope of smoke and flame around it. That’s how it appears to my eye in freeze-frame, anyhow.
Land fall and subsequent impact of a meteor of that implicate size and speed would incerate the camera and camera man. No film survives.
In retrospect that was my take as well… my untrained intuition says that even a meteorite measuring a cubic meter would have likely been traveling several times the speed of sound and would have obliterated everything within a hundred yard radius.
/dig how mix yards and meters in the same paragraph?
/dig how “I” mix, even…
Another post that reminds me why I love this board.
OK, my guess had been that there would have been a lot more destruction. It looks like you’re saying that’s not necessarily the case. But everything you said makes me say “why?”
Why should there by any velocity limit for a meteor of any size? If it’s going very fast to begin with shouldn’t it still be going very fast when it hits the earth despite friction? Terminal velocity doesn’t apply to things coming very rapidly from outside the atmosphere does it?
Why not black smoke? Assuming it still could still be burning would it have white smoke?
Is compressive heating the same thing as friction?
ps
I was completely oblivious to the spacerock hitting the truck when I wrote the OP title. I watched it a few times and then still missed it, as I was so focused on the big rock and the people.
I was even sober… I must have been running pure [del]nitromethane[/del]testosterone.
I actually thought the rock was supposed to have hit in front of the truck not on it.
I thought it was well done, even if it isn’t real.
If they were really hardcore they’d have [del]thrown a full bottle[/del] had the meteor in the back of the truck at the end.
All else being equal, smaller objects will be slowed more by atmospheric drag than larger ones. The reason is that as an object’s size decreases its cross-sectional area decreases with the square of the radius, but its mass decreases in proportion with the cube of the radius. Thus, the force exerted by atmospheric drag will have a larger effect in slowing the smaller object.
It’s not that it couldn’t be black, necessarily, but rather that it couldn’t have been so thick. If it’s moving fast enough for compressive heating to burn off the surface of the meteor (many times the speed of sound), then any trail of particulate matter would be fairly spread out and tenuous.
Not quite. If you’re familiar with the gas laws, such as the ideal gas law where PV=nRT (P=pressure, V=volume, n=number of moles of gas, R=the universal gas constant and T=absolute temperature), you’ll know that as the pressure increases, the temperature will also increase, all else being held constant. Since meteors enter the atmosphere at many times the speed of sound (typically around 25 km/s), the air in front of them can’t move out the way fast enough and so piles up and compresses, causing the heating. Frictional heating is caused by air rushing over a surface. It plays some role in meteor burning, but by far the largest effect is from compressive heating.
Nobody has filmed an imitation of a larg meteor impact that seems realistic.
Things orbit the sun at tens of thousands of mph. Depending on where a meteoroid was coming from, it could conceivably be moving 30,000 to 100,000 mph. A big one could pierce the atmosphere without slowing much. Something approaching the ground at this speed would create a remarkable impression, but you wouldn’t know which way it was moving. All you’d be able to understand was that something happened along a line between the ground and the sky, and it was as impressive as a billion pound shithammer.
When something goes through air that fast, maybe there’s compressive and frictional heating, but more dramatically there is ionization of the air, such as happens in the center of a lightning bolt. So, the entire trail can become luminous at once - that’d be the most remarkable thing you’d see in the sky. No glowing rock, just a long, wide, smooth, brilliant lightning bolt, with an incredible deafening sonic-boom bang that trailed away as you heard further and further parts of the air event.
So, then this thing has hit the ground, and you’re picturing those big rocks you hove into the mud from a bridge, picturing a crater splashing away from it. But no. The thinng pierces straight into the ground like a bullet into flesh, and wreaks havoc down below. It goes quite a way before eventually disintegrating and coming to a stop. But all its kinetic energy, proportional to the square of its insane velocity, is now heat, and many many tons of rock have just been turned into superheated gas under fantastic pressure. And what a boil does over a few days, this white hot bubble does in milliseconds. It bursts out of the ground, opening a huge bowl, and rockets an enormous mushroom cloud into the air, and darkens the sky for days with grit and ash blown higher than the blue of the sky.
Shoot. Why doesn’t somebody film that???
My last point of confusion, I guess. I understand that the atmosphere slows down small things more, butl I still don’t see why there should be an absolute maximum velocity of - say - a football-sized meteor (assuming it’s football-sized when it hits the ground, not when it enters the atmosphere) - since there’s no maximum initial velocity. Basically to me it sounds like you’re saying there’s a terminal velocity regardless of the initial velocity. Or is it that the initial velocity needed to exceed the terminal velocity for a small meteor would have to be so fast you essentially wouldn’t encounter it in nature? And is the upshot of this that a small meteor won’t be going any faster than if it were dropped from an airplane?
After that beautiful description? No need any longer.
Kinda sorta. Terminal velocity is dependent upon the density of the air, the mass of the falling object, its cross-sectional area and its geometry and/or texture. Whether or not an object actually reaches terminal velocity depends on how long the air has to act on it before it hits the ground, which in turn, depends on its initial velocity.
From here: