This is Scientific American's 60-Second Science. I'm Steve Mirsky. Got a minute?
In recent days both the unmanned Antares rocket and the Virgin Galactic space plane had catastrophic failures.
Because space is a very risky business and it always has been.
November 5th marks the 50th anniversary of the launch of Mariner 3, America's first mission to Mars.
But don't expect any NASA celebrations.
The mission failed completely.
When Mariner 3 reached space, it was supposed to unfurl solar panels.
But a glitch kept the panels tucked away.
With only battery power, the spacecraft went dead just eight hours and 43 minutes later.
So Mariner 3 fell silent, although it presumably did fly past the Red Planet months later.
Fortunately, NASA had an identical spacecraft ready for Mars.
After hasty modifications to prevent the same problem, Mariner 4 blasted off on November 28th, 1964.
The following July it became the first ship to fly past our planetary neighbor that we're sure of.
But this successful mission shocked researchers.
Back in 1964 even some respected scientists thought that Mars was home to primitive life, if not the intelligent beings that colorful astronomers like Percival Lowell imagined.
And the cameras on Mariner 4 sent back pictures of a barren, cratered world, devoid of any obvious Martians.
Thanks for the minute, for Scientific American's 60-Second Science. I'm Steve Mirsky.
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