If I shot a 200 kg mass at 20 kilometers/sec towards the Sun, where should
I point so that it will actually be absorbed by the Sun and not go into orbit?
Hmmm...let me see. The orbital speed of the earth is 29.8 km/sec so to get an object to fall into the sun you have to subtract this speed from its velocity vector. This means you have to shoot the object back along the orbit of the earth..90 degrees to the sun! Your 20 km/sec speed aimed in the same direction would cancil all but 9.8 km/sec of the speed so the object will end up in an orbit that doesnt reach the sun at all. My celestial mechanics is not good enough to tell you the details.
NASA has considered a probe called Solar Probe. With a hopeful launch in 2007, it will use a gravity assist from Jupiter to remove most of its terrestrial orbital speed and allow it to fly by the sun during a 4 year mission.
Copyright 1997 Dr. Sten Odenwald
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