Part 2: Measuring the Scale of Planetary Features

jupiter redspot

The exercises you are able to complete in this section will depend on what features are visible in your images. Some features, such as Jupiter's Great Red Spot, may be hidden on the far side of the planet if the images were taken at the wrong time. Atmospheric conditions on Earth may also render some features indistinguishable.

Your instructor may provide you with images to supplement your own, or may have you share your own images with groups who were less fortunate in their observations.

Jupiter's Red Spot

•аAdjust the contrast until you can identify the Great Red Spot on Jupiter's surface. Measure its extent in pixels and convert to an angular size.

•аDetermine the distance to Jupiter from Earth at the time of your image and find the physical size for the Great Red Spot.

•аCompare to the diameter of Earth. Is the spot larger or smaller than Earth? The largest cyclonic storms on Earth cover an area roughly the size of the Gulf of Mexico. How many times larger than this is the Great Red Spot?

Jupiter's Cloud Bands

•аAdjust the contrast until you can clearly see cloud bands on Jupiter. Measure the width of the cloud bands you can distinguish.

•аConvert the widths to physical dimensions in kilometers by finding the distance from Earth to Jupiter at the time the images were taken, as in the section above.

Saturn's Ring System

•аAdjust the contrast until you can identify the rings around Saturn. Measure the outer and inner edges of the rings you can see.

Convert the ring diameter and width to physical dimensions in kilometers.

•аFind the width and diameter of the rings in your image as a ratio of Saturn's radius. Can you identify which rings are visible in your image? (HINT: the diagram below shows Saturn and its rings to scale)

Saturn System IMG000808
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