I understand that as the distance between the planet and the body increases, the gravity decreases, but how can they still just 'float away'?
Asked
Active
Viewed 73 times
-1
Qmechanic
- 201,751
laurelberry-
- 11
-
2Because they are in free fall. – Nemo Jun 30 '18 at 21:43
-
@Andreigeanta, why not give a short explanation of free fall and post it as an answer? – niels nielsen Jun 30 '18 at 21:44
-
4Possible duplicate of Weightlessness for astronauts – Stéphane Rollandin Jun 30 '18 at 23:35
-
Heh heh. Because they are not wearing heavy boots. http://www.phys.ufl.edu/~det/phy2060/heavyboots.html – Jul 01 '18 at 03:52
-
Not clear what you are asking. Can you give an example of when this has happened? – sammy gerbil Jul 01 '18 at 09:25
1 Answers
1
If something "floats away" from a space station in orbit around Earth, it does not actually float away from Earth. It stays in orbit around Earth. Its orbital trajectory just changes a bit, compared to the orbital trajectory of the space station. So, looking from the station, it looks like the object is floating away.
The distance between the object and the station does not grow infinitely. They periodically approach each other, as they orbit Earth.
For an object to "float away" from Earth, it needs to achieve escape velocity. In such case, the Earth gravity keeps slowing the object down, but the distance is growing in such a rate, that the gradually weakening gravity never reduces the speed to zero.
mpv
- 5,220
-
Good answer as far as it goes, but it's not obvious to me that the OP understands what an orbit is. – Solomon Slow Jun 30 '18 at 23:58