Asked by: Carl Redgrove, Milton Keynes
Discovered by an American student named Gary Flandro in the mid-1960s, the slingshot manoeuvre usually involves spacecraft briefly ‘coat-tailing’ a planet orbiting the Sun, extracting some of the orbital energy to gain a big boost in speed. While the Sun has a strong gravity field, it’s hopeless as a slingshot, because (as Galileo pointed out) it’s the stationary heart of the Solar System. As such, it has no orbital energy to pass on to the spacecraft.
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