SRL Archive - Science

Hey guys, so I am doing Physics Coursework at the moment and we have been told to come online and find out some things :)
The question in which I am lacking is:

An artificial satellite is to be placed in orbit around Mars.
- How could this be done?
- Once the artificial satellite is correctly placed in orbit above Mars it stays in orbit. Explain why.

If you guys could give me some Shmexy links (no wikipedia or answers please :) ) I would be awesomely grateful.

Thank you :) <3

http://www.nasa.gov/worldbook/artificial_satellites_worldbook.html

Can't read it all right now (I will later though; :) I <3 learning), but I assume it's all top-tier info; straight from NASA.

My guess for your questions..

If an object were to be "pushed" from somewhere in space to an area close enough to Mars that it would be pulled in by it's gravitational pull, it would orbit Mars. Similar to how we have constantly orbiting space stations (and the moon, of course). Those objects have to be going at a certain speed to stay in orbit. If they go too slow, then they will be pulled down (towards the center of the earth). If they go too fast, they will be launched into space. Ever played with gravity? Hold a quarter on it's edge by your finger tip and a flat surface. Flick the edge of the quarter. It will stay relatively straight up and down (if you were to draw a straight line in the middle of it and the two points of the line were touching both you and the flat surface when you flick it) for a little bit, but as gravity pushes it down, it starts to wobble and eventually falls on one of it's two faces (heads or tails). This is similar to how satellites work, from what makes sense to me (I've never researched this; it just makes sense to me).

Think of when you first flick the quarter. It will wobble and move around a bit. Something similar to this would happen (I assume) if it were to be added into the pull of something like a planet. It would orbit in an elliptic fashion rather than circular, and it would be quite irregular. Hard for me to explain in words, but kinda like it would start to sling shot and then be pulled back in at an odd angle and speed, unless it were to go too fast. After it starts to level out (the object would be at a constant, "perfect" (can't literally be perfect, but it is valid conditions to stay in orbit) speed and orbit), it is at the ideal speed to orbit. Eventually the quarter slows down and starts to become parallel to the flat surface, ultimately laying flat with no movement. This shows the object becoming too slow and then crashing onto the planet.

Hope that helps and makes sense. :) Dunno if anything I said is right, as I have done absolutely no research or asked anyone about it. It makes sense to me, so yeah.

From: The Man

- Once the artificial satellite is correctly placed in orbit above Mars it stays in orbit. Explain why.

Thank you :) <3

For the answer to this one think about why our moon orbits around us and you should know the answer. ;)



At least I think it's that same idea.

Mars pulls the satellite towards its center (acceleration). Its velocity is tangent to its acceleration. It just needs to fulfill the formula a=(v^2)/r in order to stay in orbit. Since if it follows that formula, you'll notice that the satellite will not decrease in distance from the center of Mars (actually, it will, but not significantly)

^ This :D. Centripetal Force and whatnot, just always remember your Kinematics Equations and you should be fine :D

Technology is very useful for human life.Satellite is also part of the technology.Satellite is give us the information about natural calamities further. Satellite gives us photos of the useful matters, either it is of other planet or earth.

From: pyroryan
Mars pulls the satellite towards its center (acceleration). Its velocity is tangent to its acceleration. It just needs to fulfill the formula a=(v^2)/r in order to stay in orbit. Since if it follows that formula, you'll notice that the satellite will not decrease in distance from the center of Mars (actually, it will, but not significantly)

This, also the satellite is technically always "falling" but will never hit the earth due to centripetal acceleration.

That was a bit of a gravedig, but if anyone's interested, a scientist came and gave a presentation on the proposed Space Elevator idea, which ties into orbital mechanics:
http://en.wikipedia.org/wiki/Space_elevator