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Modelling the solar system
Astronomy begins when we look up and start asking questions. Where are we? How big is the earth? This lesson is for all ages, start here!
Change your model of the universe by selecting from menu.
The three brightest planets in the night sky on May 26th, 2013 lined up for a beautiful sunset conjunction.
When the moon passes through the Earth's shadow, it causes the moon to look very unusual for a short period of time. This event is called a lunar eclipse, and it occurs roughly twice a year.
The red dot represents your position on the earth.It's on the equator and assumes the earth's axis is perpendicular to its orbit with the sun and moon. The top of the screen shows what you see as you look into the sky.
Challenge: Use sliders to simulate a lunar eclipse.