Serious question, how does it stop when it gets to the right place? Does it have to thrust in the opposite direction or does it use some gravitational effect to slip into orbit?
Picture rolling a ball up a hill. If you don't roll it fast enough it will roll back down before reaching the top. If you roll it too fast it will go over the top and roll down the other side. Just right, and it will stop at the top of the hill. But being at the top of the hill, it's an unstable orbit, and any small drift will end up with the ball eventually rolling back down the hill. That's why occasional course corrections are required, and why the lifetime of the satellite is determined by the amount of fuel it has.
It's like bowls, or curling (the sports). It's a million mile curl. At the end of the curl, the telescope has close to zero radial velocity with respect to Earth (that is, its orbit around the Sun is parallel to Earth's and has the same period). At that point there will be an orbit injection burn to put it into a small elliptical orbit around the Lagrange point.
The telescope slows down over time due to Earth’s gravitational pull. IIRC the trip to L2 was all driven by momentum after the rocket released it. The rocket boosted it in the right direction/speed so that gravity would slow it to a stop at the right place.
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Serious question, how does it stop when it gets to the right place? Does it have to thrust in the opposite direction or does it use some gravitational effect to slip into orbit?
Picture rolling a ball up a hill. If you don't roll it fast enough it will roll back down before reaching the top. If you roll it too fast it will go over the top and roll down the other side. Just right, and it will stop at the top of the hill. But being at the top of the hill, it's an unstable orbit, and any small drift will end up with the ball eventually rolling back down the hill. That's why occasional course corrections are required, and why the lifetime of the satellite is determined by the amount of fuel it has.
It's like bowls, or curling (the sports). It's a million mile curl. At the end of the curl, the telescope has close to zero radial velocity with respect to Earth (that is, its orbit around the Sun is parallel to Earth's and has the same period). At that point there will be an orbit injection burn to put it into a small elliptical orbit around the Lagrange point.
The telescope slows down over time due to Earth’s gravitational pull. IIRC the trip to L2 was all driven by momentum after the rocket released it. The rocket boosted it in the right direction/speed so that gravity would slow it to a stop at the right place.
"...Webb will orbit around L2, not sit stationary precisely at L2..."
https://webb.nasa.gov/content/about/orbit.html