How to get an obect to stop rising?

  • Thread starter Thread starter jehan60188
  • Start date Start date
AI Thread Summary
To stop a rocket's vertical ascent and initiate orbit around Earth, it must gain significant horizontal velocity, typically around 16,000 mph. Rockets initially launch vertically but quickly tilt to build horizontal speed, which is crucial for achieving orbit. Once in orbit, minimal energy is required to maintain that position due to negligible atmospheric friction, although occasional burns may be needed to counteract orbital decay. For interplanetary travel, such as to the Moon or Jupiter, rockets must achieve escape velocity and carefully time engine burns to adjust their trajectory, potentially utilizing gravity assists from other celestial bodies. Effective navigation involves balancing time and fuel efficiency to reach the desired destination.
jehan60188
Messages
201
Reaction score
1
once a rocket is launched vertically, how does one stop it's rising, and start it into an orbit around earth?
actually, the only thing I can really fathom is launching a rocket straight up, and having it fall back to earth, or having it leave Earth's gravity, and drift off into whatever trajectory the universe selects for it
so, how about getting it to the moon, or steering a probe to jupiter?
thanks!
 
Physics news on Phys.org
jehan60188 said:
once a rocket is launched vertically, how does one stop it's rising, and start it into an orbit around earth?
It takes very little of a rocket's energy to get it from 0 alt to 100 miles. The vast majority of the energy is put, not into altitude, but into horizontal velocity. A satellite needs to be moving at 16,000 mph to achieve and remain in orbit.

When you watch rockets lift off, you will see them go straight up only for a very short period, they almost immediately tilt and gain speed over ground. That's the key to orbit.
 
how does that happen? thrusters? fins?

once an object is in orbit, it's my understanding that it takes very little energy to keep it there (since there's negligible friction). is that an inaccurate statement?

what about getting to the moon or jupiter? is it just another degree of tilting?
 
jehan60188 said:
how does that happen? thrusters? fins?
Thrust vectoring nozzles: The nozzles move.
once an object is in orbit, it's my understanding that it takes very little energy to keep it there (since there's negligible friction). is that an inaccurate statement?
It is accurate.
what about getting to the moon or jupiter? is it just another degree of tilting?
And additional speed, yes.
 
jehan60188 said:
how does that happen? thrusters? fins?
Yes and/or yes. Fins rapidly become useless so usually it's a matter of angling the main propulsion.

jehan60188 said:
once an object is in orbit, it's my understanding that it takes very little energy to keep it there (since there's negligible friction). is that an inaccurate statement?
It is an accurate statement. Except for the occasional compensatory burn for orbital decay due to atmo friction, it takes zero energy to keep in orbit.

jehan60188 said:
what about getting to the moon or jupiter? is it just another degree of tilting?
An interplanetary journey is about firing up your engines to achieve escape velocity - your orbit spirals outward. You must time your burns and do corrections so that you hit your next target, which might be a gravity-assist from another planet. Depending on whether you want to optimize time or fuel, you choose different journeys. Some journeys can visit more than one planet, or even the same planet on several successive passes before ending upon a final path to your destination.
 
comparing a flat solar panel of area 2π r² and a hemisphere of the same area, the hemispherical solar panel would only occupy the area π r² of while the flat panel would occupy an entire 2π r² of land. wouldn't the hemispherical version have the same area of panel exposed to the sun, occupy less land space and can therefore increase the number of panels one land can have fitted? this would increase the power output proportionally as well. when I searched it up I wasn't satisfied with...
Back
Top