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syano
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If the Earth did not have an atmosphere could you make a golf ball orbit the Earth just 1 foot above the highest point of the crust of the Earth?
syano said:Is this right...the closer the golf ball is to Earth the faster it will need to move to maintain a steady orbit?
That's wrong.ShawnD said:[tex]V^2 = \frac{Gm_1m_2}{r}[/tex]
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Gokul43201 said:2. None. Any change in the one will cause a change in the other. If the velocity is low by 1%, the station will approach Earth at an acceleration of about '2% of g' or 0.2 m/s^2. In the first 10 seconds the orbit will drop by 10 m. 2 minutes later, it will be closer by about a mile, and 10 minutes later, by 100 miles. The way to get it right is to (i) to be close at the beginning and then (ii)continuously monitor and adjust.
3. I think the Blackbird has turbofan engines which requires oxygen to burn the fuel.
4. The escape velocity depends on the drag from the atmosphere. There will be less drag in the moons atmosphere, since that's much thinner, so you'll need a smaller addition to compensate for drag. However, this number is not one-sixth that of Earth's. The escape vleocity (neglecting drag) is SQRT(2*G*M/R). I don't know the ratio of the masses and radii, but if you plug them in, you get the ratio of the rough escape velocities.
5. To quantify how much harder it would be, you would need to specify the orbital height (and perhaps, several other things). There may be other complications involved in stability and control, but typically, the required take off velocity will have to be greater by about 1%. This, however, is not a small number, when it comes to fuel costs and such.
Nereid said:Going east, you get the Earth's speed at the launch point (relative to the centre of the Earth) 'for free', and if you're on the equator, you maximise it. That's why the ESA's main launch site Kourou is only 5o N, the US's in Florida, and Russia's in Kazakhstan. IIRC, Israel, when it launched its first spacecraft , wanted to launch west (for political reasons).
A low orbit is a path around a celestial body, such as Earth, that is relatively close to the surface. In the case of Earth, a low orbit is typically considered to be between 160 kilometers and 2,000 kilometers above the surface.
Earth's atmosphere plays a crucial role in maintaining low orbits. It provides drag or resistance that slows down objects in orbit, causing them to eventually fall back to Earth. Without this drag, objects in low orbit would continue on a path in space without ever returning to Earth.
Yes, low orbits could still exist without Earth's atmosphere. However, they would be significantly different than they are currently. Without the drag from the atmosphere, objects in low orbit would not experience any resistance and could potentially remain in orbit indefinitely.
Without the drag from Earth's atmosphere, satellites in low orbit would not need to constantly adjust their speed and altitude to maintain their orbit. This could potentially lead to longer lifetimes for satellites in low orbit.
Other factors such as the gravitational pull from the Moon and other celestial bodies, as well as Earth's own gravity, would still influence low orbits. However, the absence of Earth's atmosphere would greatly impact the stability and longevity of objects in low orbit.