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Jupiter, Mercury, Mars to cluster in predawn

CAPE CANAVERAL, Fla. -- Stargazers will get a rare triple planetary treat this weekend with Jupiter, Mercury, and Mars appearing to nestle together in the predawn skies.

About 45 minutes before dawn tomorrow those three planets will appear so close that the average person's thumb could obscure all three from view.

They will look almost as close together today and Monday, but tomorrow they will be within one degree of each other in the sky. Three planets haven't been that close since 1925, said Miami Space Transit Planetarium director Jack Horkheimer.

The planets are actually hundreds of millions of miles apart, but the way the planets orbit the sun make it appear they are neighbors in the east-southeastern skies. They'll be visible in most of the world -- in the Western Hemisphere, as far south as Buenos Aires and as far north as Juneau, Alaska, Horkheimer said.

The way to find the planets, which will be low on the east-southeast horizon, is to hold your arm straight out, with your hand in a fist and the pinky at the bottom. Halfway up your fist is how high the planets will appear above the horizon, Nichols said.

Jupiter will be white, Mercury pinkish, and Mars butterscotch-colored.

In ancient times, people thought the close groupings of planets had deep meaning, Krupp said. Now, he said, "it's absolutely something fun to look for."

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