Finding evidence for the seasons should be easy, but in this day of photo shop and false news, finding solid evidence for the "reason behind the seasons" is becoming a challenge. What is evidence for the seasons? #1 Reason for the Seasons: The tilt of the Earth's axis. Long, long time ago it is believed by most scientists that something big hit the Earth and knocked it off it's straight-axis rotation. The big thing even has a name...Theia. This big "Theia" knocked off a chunk of Earth into space and we call that our "Moon" now. Yes! That was a long time ago...but it's a theory that is accepted by many scientists....and I'm sure there are some astronomers somewhere trying to bust that theory....because we can! Humans are curious creatures. Because the Earth is tilted, some parts of the Earth get direct rays from the sun and other parts get indirect rays from the sun. This leads us to the #2 reason for the Seasons: The angle of sunlight that hits the Earth is either direct (hot) or indirect (cooler). When the Earth was tilted, it continued to revolve around the Sun at the same angle of tilt = 23.5 degrees, (plus or minus a few degrees). When the parts of the Earth that are tilted toward the Sun, receive the heat energy from the Sun, it is more direct on those parts. In the Northern Hemisphere we are tilted toward the Sun in the summer, that is when we have our longest days and warmest days. On the opposite, or southern side of the Earth, it is tipped away from the Sun and receives less sunlight (energy) and has cooler and shorter days. How do we know this is true? What is the evidence? Well, we live it. We have experienced it. If you were to travel in a plane from the Northern Hemisphere to the Southern Hemisphere during a Northern winter, you will find out pretty quick that you shouldn't have worn your heaviest coat, but brought your shorts and swimming suit! We know what summer looks like... And we know what winter looks like... It's not happening at the same time at the North and South Poles. So something must be...tipped! The best evidence is what we experience, observe and test. After all the thinking and testing, scientists have shown through models and simulations that an Earth tipped on it's axis is true. And, this causes the seasons because the energy from the sun is direct at the area in the middle of the Earth and indirect at the North and South poles.
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Mrs. TaylorI love science! Everything about the world is interesting and never boring. I love to study plants, animals, insects, and people. My favorite subjects are my students who are the most unique organisms on the planet! Categories |