How does the phenomena of "seasons" occur. Why would it be summer inMaryland when it is winter in the southern hemisphere?Does the moon have seasons?

The Earth has seasons because it is tipped over to one side. It stays tipped in the same direction as it travels around the Sun. This means that sometimes the "top" of the Earth (which we call "north") is pointing towards the Sun, and sometimes it is pointing away.

When the north half of the Earth is pointing towards the Sun, that half gets more sunlight and is warmed by the Sun. This is summer for people on the northern half of the Earth. At the same time, the "bottom" half of the Earth (which we call "south") is pointed away from the Sun. During the time that it's pointed away, that half doesn't get as much sunlight, so it is colder. This is winter for people on the southern half of the Earth. When the Earth completes half of its orbit around the Sun, the north end will be pointed away and the south end will be pointed toward the Sun and the seasons will switch! This is why seasons in the south are always the opposite of seasons in the north!

Suppose the Earth were straight up and down. Then everybody would have the same season all year round. No more summer and winter!

The Moon is nearly straight up and down. So each spot on the Moon has the same "season" all year. Even if the Moon had seasons, they would differ from seasons on Earth. There is no air on the Moon, so there can never be April showers, or snow for snowmen, or even wind for flying kites. All of these things happen on Earth because it has an atmosphere.

Submitted by Joan (Massachusetts, USA)
Submitted by Alex (Maryland, USA)
(October 22, 1997)

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