# The Naked Scientists Forum

### Author Topic: How is the orbital period of a satellite controlled?  (Read 1650 times)

#### Sam

• Guest
##### How is the orbital period of a satellite controlled?
« on: 11/12/2009 12:30:02 »

If the moon takes 28 days to orbit the Earth does that mean it also takes artificial satellites 28 days to orbit the Earth?

What do you think?

#### graham.d

• Neilep Level Member
• Posts: 2208
##### How is the orbital period of a satellite controlled?
« Reply #1 on: 11/12/2009 13:17:22 »
No, the time to orbit (for a circular orbit) is just dependent on its distance from the earth.

#### syhprum

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##### How is the orbital period of a satellite controlled?
« Reply #2 on: 11/12/2009 22:33:49 »
If you could fly around at near ground level (as you can do on the Moon) you could get around in 84 minutes but in practice the lowest orbit that has a reasonable life takes about 90 minutes.
The orbital time neglecting atmospheric effects depends on the density of the object you are orbiting, (for the Sun it would be 55 minutes but rather hot!)

#### Geezer

• Neilep Level Member
• Posts: 8328
• "Vive la résistance!"
##### How is the orbital period of a satellite controlled?
« Reply #3 on: 11/12/2009 22:54:39 »
If you select the right orbit, the satellite will take 24 hours to circle the earth, so if the orbit is along the equator (and going in the right direction) the satellite will appear to be parked above the same point on earth. These "geostationary" orbits are quite far from the earth.

#### The Naked Scientists Forum

##### How is the orbital period of a satellite controlled?
« Reply #3 on: 11/12/2009 22:54:39 »