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Modelling the solar system

4 articles
1 program
2 videos
2 talkthroughs
1 skill
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!

INTERACT: Models of the solar system

TALKTHROUGH
Change your model of the universe by selecting from menu

Conjunctions

VIDEO 3:06 minutes
The three brightest planets in the night sky on May 26th, 2013 lined up for a beautiful sunset conjunction.

Lunar eclipse

VIDEO 1:47 minutes
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.

ANIMATE: Phases of the moon

TALKTHROUGH
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.

INTERACT: Lunar eclipse

PROGRAM
Challenge: Use sliders to simulate a lunar eclipse.

Modelling the solar system

PRACTICE PROBLEMS