Hello everyone, I have a theoretical question about an animation in the documentary I’ve linked in this post.
At timestamp 05:01, you can see an animation of Venus, suffering the effects of a change in gravitational forces. After being close enough to the expanding sun, Venus begins to lose material on its surface due to the stronger gravitational pull of the sun.
For me, this whole animation doesn’t seem right because the mass and the center of mass of the sun doesn’t change. I can imagine how the mater of the sun’s surface could change the gravitational pull that the material on Venus’ surface is experiencing, but would it be that strong at that point? I would’ve assumed that more and more of the sun’s mass will be concentrated in the core as the red giant is expanding and not leaving enough mater to overcome Venus’ gravity at its surface.
Once, Venus enters the denser parts of the suns’ atmosphere, I wouldn’t doubt that the atmospheric drag or the fall towards the denser core would scatter the material on the surface and eventually destroy Venus completely. Shortly before that, however, while Venus is still roughly maintaining an orbit similar to its current one, this doesn’t seem right to me.
Did they mess up this animation or will the sun, at its surface, have more gravitational pull than Venus?
I would presume they had the animation first, either found it or made it, and they liked it, so they created simplistic dialogue with it as a visual centerpiece instead of giving you a more complex scientifical explanation. While I don’t like it when they do this without being clear, it’s all theory anyways.
We know very little about the workings of the universe because of its extreme longevity. We see one frame of a movie and try to surmise the movies entirety based on that one frame. You don’t know if you’re looking at the protagonist, the antagonist, an ancillary character, or even a commercial break.