In 2016 the Flat Earther Dave Murphy, who is a notable figure in the greater Flat Earth community, had a few questions for Neil deGrasse Tyson. Tyson has still not responded, although he has most assuredly seen it. There are a few good points to think about in this video.
I wish such notable figures would participate in forums like this. I'm not Neil, but I'll try to answer Dave's questions. I'll send him an email, pointing him to this thread. Maybe he'll join us and respond?
1.
Why is there land at the equator? Water does contribute to the bulge of earth's oblate shape, but rock is subject to the centripetal force of earth's spin too; and the effects of that centripetal force are smaller than other tectonic forces that cause rock to rise above the bulge of water. The "oblateness" is very small relative to the size of the earth. Forces causing movement of land masses are greater than the 1/3G force of centripetal spin.
And the condition is not constant. Changes occur over long periods of time. Sometimes the land does bulge less and water, if melted, moves due to the spinning force and covers more land. It's dynamic.
2.
Am I able to see the curvature or not? Curve in the lateral frame? (Across the horizon left to right or right to left?) No. You cannot see that curve. That curve would be the circumference of a spherical cap of the earth, which is too gradual at low elevations to detect.
Curve in the transverse frame? (Toward and away from the horizon?) You can "see," but only by inference. You can't see curve away from you directly. You see along a line tangent to the surface. But you can deduce that there is curve away from your vantage point.
3.
Why haven't we ever seen curved water? By "see" I assume you mean "detect." The curve is too gradual to see. But it can be detected, and has been.
4.
How are we breathing? Gravity.
Air, whether warm or cold, has mass. Some actually does "leak" away into space, but not due to the vacuum of space. The gas in a bottle analogy is not a correct model for the atmosphere of earth. In the bottle example, gravity exists both inside and outside of the bottle, so locally, the gas will seek equilibrium and the "vacuum" effect will occur. But the earth's atmosphere is not contained by boundary between vacuum and non-vacuum. Gravity creates a virtual boundary of sorts that causes the non-vacuum state of air to even exist. If gravitational force suddenly disappeared, the atmosphere would get "vacuumed" away. But were it not for gravity, there'd be no atmosphere at all for there to be vacuum and non-vacuum.
5.
Is the Earth small or the Sun near? I've never heard anyone give the "official explanation" being refraction for the phenomenon of crepuscular rays. The "official explanation" is they are nearly parallel and only appear to radiate due to perspective.
Since the suns rays are not divergent as they appear, but are parallel, the apparent disjunction re. Eratosthenes' shadow observation that you raised should be resolved.
6.
How does a convex lens make light diverge? It doesn't. You're right. A convex lens doesn't make light diverge. The refractive index of earth's atmosphere causes light to bend (to about half a degree at most) toward the more dense medium. Explaining crepuscular rays as light bending toward area of less density would be in error and thus an incorrect explanation. (Who told you this "official explanation?")
7.
Why doesn't the artificial horizon roll backwards during straight and level flight? What manufacturer of attitude indicators did you talk to? There is no reason why they shouldn't have explained that the instrument is self-leveling, relative to the axis of gravity's force. They aren't merely a gyroscope with a fixed orientation in space. They do adjust, by design, for the change in axis due to gravity. (Speaking as a former aviator, I'm surprised the pilots didn't explain this to you also.)
8.
Why is the Coriolis effect so selective? Bullets are ballistic. Airplanes are not. The Coriolis effect is greatest in north/south movement and lessens as the east/west component of path increases. The effect is slight, but for gunnery over distance, accuracy requires accounting for the effect.
Planes moving over the surface of the earth will be affected by the earth's rotation under it, though it is slight and other influences (like wind) are much more impactful. Even at its greatest -- in an aircraft flying due north or due south -- the effect is not like having to crab into the wind as your video shows by false analogy. Planes (and bullets) retain the rotational momentum of the earth after taking off (or leaving the barrel). Planes, however, are guided. Bullets (mostly) are not. Either way, it's a misunderstanding to believe that the Corolis effect is selective.
9.
What is the ISS flying over? The view from low earth orbit is steeper than the view from an airplane cockpit near the earth's surface. It's the like how cruise at high altitude in a commercial airliner doesn't have the same "land rush" as flying low level like in a crop duster or strike fighter.
10.
How can micro gravity be selective? Gravity isn't selective. I can't offer a definitive explanation for that ketchup bottle. Looks to me like it's magnetized, but that's just my guess. Whatever the explanation, evidence of a hoax would be low on my list of possible solutions. For example, I might not rule out the explanation that a ghost is responsible for a sound heard coming from my attic, but I'm inclined to inspect and rule out other explanations first.
11.
Why are there craters on the Moon? The moon has no atmosphere and other eroding factors, so old crators remain in evidence. Earth's gravity does "protect" the moon to a degree, just as the larger outer planets and sun protect the earth from experiencing more impacts. But it isn't a shield. Some impacts will still occur on a satellite of a larger body.
And as for the tidal lock, the moon wasn't always oriented to earth the way it is now. It takes time for that to occur. (The 'far side' of the moon does look more crator-impacted to me than the 'near side,' though I don't know if that's actually true.)
12.
Why don't we see permanent hills and valleys in the ocean? I didn't understand what this question was asking until I saw the graphic of sea surfaces comforming to undersea terrain.
All things with mass are affected by gravitational force. But collectively, the force vectors combine to direct toward center mass. Terrain undulations have negligable effect compared to the earth on whole. The gravitational effects of localized masses like mountain ranges or deep sea rifts (lack of mass) are vastly overwhelmed by the aggregate gravitation of the rest of earth.
I welcome any response or rebuttals from Allegedly Dave (or Mark Sargent, who posted that video).