Coronal Mass Ejections

Coronal Mass Ejections are among the fleetest storms in the solar system. The pictures above, taken with the NASA/ESA SOHO satellite, show a CME lifting off from the Sun on April 7, 1997. The picture on the left was taken at 2:50 PM. The one on the right was taken at 3:30 PM. The white circle at the center shows the diameter of the Sun.

1...On the computer screen, measure the diameter of this circle with a metric ruler.

2...The diameter of the Sun is about 1,400,000 kilometers. Calculate the scale of the TV image in kilometers per millimeter.

3...Measure the distance in millimeters from the center of the Sun disk to the outer edge of the lobe of gas seen in the left image at the lower left.

4...Measure the distance to the edge of the lobe in the right image.

5...From the scale of the TV screen, calculate the distances to the lobe edges in kilometers.

6...From the difference in the times between the two images, and the difference in the distances of the lobes, calculate the average speed of the CME in kilometers per second.