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Comment by the_mungler | Hacker News Reader

You're right, Mexico would be a better place to launch rockets from. You want to be close to the equator, and on an east coast so you can launch rockets over the water and avoid dropping boosters on people. Rockets generally are launched to the east to take advantage of Earth's rotation (we're all moving about 1,000 mph to the east, so launching west requires about 2,000mph extra Delta v). SpaceX is a USA company, and I believe their rocket technology is considered a government secret and must stay in the USA. So that's why SpaceX themselves aren't putting launch pads in Mexico.

Also I believe equatorial orbits are still possible to achieve from USA launch sites, it just means more fuel/ reduced payload.

Interestingly, the James Webb telescope was launched from French Guiana, which is almost right on the equator.

Also Israel is one of the few countries that regularly launches their rockets to the west, as they only have a West Coast.

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If the earth is rotating to the east, and we launch a rocket that drops boosters from the east coast, doesn't that mean that the land mass would move under where the boosters would drop? Wouldn't the earth need to be rotating towards the west for it to move the land mass away from the launch site?

It you are in a room, and you jump, does the wall suddenly slam into you at 1,000 mph? Why or why not?

Because I already have momentum from the earth, but a rocket will be disconnected from the earth for far longer than I would be jumping. The path of a rocket would start to curve away from the launch site due to no longer being connected from the earth for such a long time.

1) An object will maintain its momentum forever unless some force acts upon it.

2) In the case of the rocket, it accelerates eastward. Even if parts fall off, and they slow down because of the drag of the atmosphere, and they slow down all the way to the speed of the atmosphere, the atmosphere is more or less moving eastward at the same speed as the earth's rotation, so any part would be unlikely to land any further west than where it detached from the rocket. And if there was no atmosphere on earth any part that fell off a rocket during its ascent to orbit would fall according to a ballistic trajectory and would most certainly land farther east than where it fell.

So there's no friction from the atmosphere?

"friction from the atmosphere" = drag. The previous commenter explains the effect friction has.

That's Aristotle physics.

Friction doesn't exist I guess. Spherical cow and all that?

It's more complicated than that.

For example, even though Rocket Lab was founded in New Zealand it is now a US based company. It operates launch facilities both in New Zealand and the US and pretty sure it builds stuff in both countries.

What government secrets?

Rockets fall under some pretty big restrictions government wise. You know, guided missiles and all that. While SpaceX is a private company, the people allowed to work on their rockets are very much restricted. I believe they can employ Americans and Canadians, but anyone else is not allowed to work there.

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