Fifty years ago this weekend, NASA's Mariner 9 probe went into orbit around Mars. This pioneering mission revolutionized our ideas about Mars and, with humans looking to head that way, is a timely ...

"That Mars is habitable by beings of some sort or other is as certain as it is uncertain what these beings may be," wrote Percival Lowell in the early 20th century. While other astronomers had their ...

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On November 13, 1971, Mariner 9 became the first spacecraft to orbit Mars. At the time, scientists didn't know much about the Red Planet. NASA had several flybys before Mariner 9. Those flybys showed ...

You have to feel for Mariner 9. First, the spacecraft loses its twin, Mariner 8, in a launch failure just weeks before Mariner 9 itself was scheduled to blast off toward Mars on May 30, 1971. Not only ...

As much as we know today about the planets of the solar system, it’s almost incomprehensible that a mere 50 years ago we knew almost nothing about them. Observations of even Mars and Venus, Earth’s ...

Pasadena, California (CNN) — Just steps away from High Bay 1, where many of NASA’s pioneering robotic missions have been assembled, is the first image of Mars ever seen on television, broadcast in ...