SAN FRANCISCO -- Venus and Mars, planet Earth's two closest neighbors, have been inching ever closer to each other during the month of July.
Monday night, they promise to put on a show, appearing at their closest distance into the early hours of July 13.
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In what's called a "planetary conjunction," Venus and the Red Planet will be easily visible in the same field of view despite being tens of millions of miles apart in outer space.
The crescent moon will approach Venus and Mars above the western horizon about 45 minutes after sunset. Both planets are key targets for the next generation of space exploration.