What could cause an orbit to fail?
An orbit is the perfect balance between a satellite's forward momentum or inertia
and the pull of gravity on it. If either of these are changed, the orbit will
fail, and the satellite will either crash down onto the object it is orbiting
or spin off into space.
This rendering shows what it would look like if a large body collided with
Earth at about 40,000 m.p.h. Many scientists believe an impact like this was
responsible for the death of the dinosaurs and many other species of life 65,000,000
years ago. From NASA's Asteroid Comet Impact Hazards Gallery Page, http://impact.arc.nasa.gov/gallery/index.html
Painting by Donald E. Davis.
Here are some ways an orbit could fail:
- The satellite could collide with something in space and either gain speed
or lose it, depending on the direction of the collision. If the satellite
slows down it would crash into the object it is orbiting. If the satellite
speeds up, it may spin off into space.
- The satellite could be knocked or moved closer or farther from the object
it is orbiting. If it moved closer, gravity would pull more strongly, if it
moved farther, gravity would have less of a pull.
- The satellite could dip into the atmosphere of a planet and be slowed by
that. Sometimes this aerobraking is done on purpose to place a satellite on
a planet or put it in a lower orbit.
What is an orbit?
What causes an orbit to happen?
Is there gravity in space?
What is a satellite?
Once a ship is in orbit,
do we have to do anything to keep it there?
How can a spaceship leave orbit?
How
does speed affect an orbit?
What
is mass?
What are different
kinds of orbits?
What
is retroburning? What is aerobraking?
