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 (age 35+, Massachusetts, USA)
Submitted by Alex (age 11, Maryland, USA)
(October 22, 1997)
When the northern half of the Earth is pointing towards the Sun, the northern hemisphere of the Earth gets more direct sunlight. We call this the "summer" season for the north. At this same time, the southern half of the Earth is pointed away from the Sun, so people in the southern hemisphere get less direct sunlight. We call this "winter" for the southern hemisphere. So, because of the tilt of the Earth's axis, the seasons in the south are the opposite of those in the north.
Suppose the Earth's axis was not tilted. Then everybody would have the same season all year round! No more summer and winter! The Moon is only tipped over about 1 degree. Since it has such a small tilt, each spot on the Moon has the same "season" all year.
Even if the Moon had seasons, they would differ from seasons on the
Earth. The Moon has no atmosphere. Hence, many of the weather
phenomena which we associate with seasons (wind, rain, and snow, for
example) cannot occur on the Moon.
Submitted by Joan (age 35+, Massachusetts, USA)
Submitted by Alex (age 11, Maryland, USA)
(October 22, 1997)
When the northern half of the Earth is pointing towards the Sun, the northern hemisphere of the Earth gets more direct sunlight and we call this season "summer" for the north. At this same time, the southern half of the Earth is pointed away from the Sun, so people in the southern hemisphere get less direct sunlight and we call this "winter" for the south. So, because of the tilt of the Earth's axis, the seasons in the south are the opposite of those in the north.
Suppose the Earth's axis were not tilted; in other words, suppose the Earth was straight up and down relative to it's orbit around the Sun. Then everybody would have the same season all year round: an eternal spring! No more summer and winter! The Moon is tipped over about 1 degree. Because the Moon has such a slight tilt, each spot on the Moon has the same "season" all year.
Even if the Moon had seasons, they would differ from seasons on the
Earth. The Moon has no atmosphere. Hence, many of the weather
phenomena which we associate with seasons (wind, rain, and snow, for
example) cannot occur on the Moon.
Submitted by Joan (age 35+, Massachusetts, USA)
Submitted by Alex (age 11, Maryland, USA)
(October 22, 1997)
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