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This picture was made with a radar. It shows the area around the North Pole of Mercury. There are some white circles or "doughnuts" in the picture. The white circles might be ice at the bottom of meteor craters.
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Image courtesy of NAIC - Arecibo Observatory, a facility of the NSF (J. Harmon, P. Perrilat, and M. Slade).

Mercury's Poles

Most planets are tilted. Their North and South Poles are not straight up and down. Earth is tilted a medium amount. Uranus is tilted a lot. Mercury is hardly tilted at all. It is tilted less than any other planet. Mercury's North and South Poles are straight up and down.

Planet's that are tilted have seasons. Earth is tilted. That's why we have seasons on Earth. Mercury isn't tilted, so it doesn't have seasons.

If you were at one of Mercury's poles, you would see a strange sight. The Sun would never rise or set. It would always be at the horizon. It would always look like it was in the middle of rising or setting. If you were inside a crater, it would always be dark. The hill around the rim of the crater would block the sunlight.

Some of those dark craters near the poles might have ice in them. Scientists have taken radar images that may show ice. It would be very strange to find ice on Mercury. It is very, very hot on Mercury because Mercury is the planet closest to the Sun. The temperature is sometimes as high as 452 C (845 F). Still, there might be ice in the bottom of craters near the poles where the Sun never shines.

Last modified May 29, 2009 by Randy Russell.

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