This drawing represents the expansion of gases leaving a supernova in the form of a shock wave.
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When the wave from the supernova reaches our nebula, it squeezes the cloud of gas and dust. Squeezing makes the cloud start to collapse into a tighter ball.
Shop Windows to the Universe Science Store!
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includes fun classroom activities
for you and your students. Issues of NESTA's quarterly journal, The Earth Scientist
are also full of classroom activities on different topics in Earth and space science!