Why seasons happen

What are equinoxes and solstices? At the same time, the Southern Hemisphere points away from the Sun, creating winter during the months of June, July and August. Meteorological vs. Most scientists think that that rubble, in time, became our Moon.

As Earth orbits the Sun, its tilted axis always points in the same direction. It is summer in June in the Northern Hemisphere because the Sun's rays hit that part of Earth more directly than at any other time of the year.

It is winter in December in the Northern Hemisphere, because that is when it is the South Pole's turn to be tilted toward the Sun. And, believe it or not, aphelion when Earth is farthest from the Sun occurs in July, and perihelion when we are closest occurs in January. For those of us who live in the Northern Hemisphere where it's summer in July and winter in January, that seems backwards, doesn't it?

That just goes to prove that Earth's distance from the Sun is not the cause of the seasons. Indeed, they built hundreds of amazing stone circles — like the famous Stonehenge — all over Europe, which marked certain times of the seasons across the year.

These days, we even know how to calculate the seasons on other planets. For example, the next Spring equinox on Mars is on the 23rd March. To understand how this works, imagine a small ball representing the Earth moving around a lightbulb the Sun in a circle. If you have these things at home, you can try this yourself.

As the ball moves around the lightbulb, the half closest to the light will be lit, while the other half will be in darkness. One full circle around the lightbulb represents one full year on Earth. As you move the ball around the lightbulb, try spinning it between your fingertips, so that the light always shines directly onto the equator.

If the Earth span like this, day and night would be the same length all year round, and there would be no seasons. Now, take that small ball and tilt it at an angle, so that the light from the bulb no longer shines directly on the equator. If you are doing this at home, it might help to colour in either the top or bottom half of the ball. Why do we have seasons? The Reason for the Seasons This website gives background information of why we have seasons and visualizes the angle of sunlight one of the reason of the seasons.

Travel underground for an up-close look at the ants, amoebas, and bacteria that maintain healthy soil. Plunge into a California kelp forest and learn about the complex, colorful ecosystems right off our coast.

Browse a rich array of educational resources from the award-winning show, Habitat Earth. Our collection of educational videos will help your students visualize data and understand scientific concepts. Sign up for event updates and exciting announcements. Learn more. Reservations are required for the planetarium and are available on a first-come, first-served basis. More info. Donate Join Tickets. California Academy of Sciences. K-1st 2nd-3rd 4th-5th 6th-8th 9thth.

Toggle Close. Search calacademy. Search the Educators section. Suggested Unit Progression. Download script. Activity 1: Longer Days, Shorter Nights grades