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Encountering Neptune in 1989, NASA’s Voyager mission completed humankind’s first close-up exploration of the four giant outer ...

Want to see Mars at its brightest in January? The best telescopes for seeing planets give you the clearest views of our celestial neighbors. The new year is a great time to test out your ...

Everyone knows about the Solar System, and the planets that make it up. They’re in space, orbiting the Sun, in an order we all at least used to be able to recite. But it was not always so.