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At 430,000 miles per hour, Parker Solar Probe could cross Australia east to west in about 21 seconds; the Sun’s gravity, not its engines, makes it the fastest human-made object
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At its fastest, NASA’s Parker Solar Probe moves about 430,000 miles per hour relative to the Sun.
At peak speed, Parker would cover that coast-to-coast distance in roughly 20.8 seconds.
It is moving extraordinarily quickly near the bottom of a deep gravitational well, but remains in a bound solar orbit.
Venus helped Parker lose speed before the Sun made it fasterIt sounds contradictory that reaching the fastest spacecraft speed began by slowing down.
Parker’s speed record is therefore not mainly the result of a continuously firing engine.