Warp of the Worlds
Widely distributed emails claim--falsely--that Mars will get close enough to Earth to appear as large as the moon. Steve Mirsky and Orson Welles report.

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Audio clip of Orson Welles: “That grinning, glowing, globular invader of your living room is an inhabitant of the pumpkin patch. And if your doorbell rings and nobody’s there, that was no Martian—it’s Halloween.” That’s how Orson Welles ended his Mercury Theater version of HG Well’s War of the Worlds on October 30, 1938. The broadcast was designed to sound like live news coverage of an invasion of Earth by Martians. And a lot of people fell for it.
Now there’s some more Martian misinformation fooling folks. This one’s not so scary. A lot of people are getting email claiming that in the next few weeks the planet Mars will get close enough to the Earth so that it will appear to be about the same size as the moon. Our friends at Sky and Telescope magazine report that email dating back to 2003 mentioned that in a 75x magnifying telescope Mars would look about as big as the moon does—to the naked eye. Somewhere along the line the telescope part got lost. So don’t worry. Mars, even at its closest, is still small and safely far away.
Welles: “It’s Halloween.”
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