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[ music ] My name is David Choi, and I study the weather on giant planets.

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When we look at Jupiter we're seeing the top of its atmosphere and its weather layer,

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and its weather layer contains a lot of interesting features such as jet streams,

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vortices, storms, and these particular features called hot spots.

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So hot spots are like holes in the clouds because they appear very dark when observed in visible light,

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but in near infrared light they appear very bright,

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and this indicates that we're seeing deeper down into warmer layers of the atmosphere.

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Hot spots have been previously studied by the Galileo atmospheric probe.

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In 1995 the spacecraft released a probe that descended into Jupiter's atmosphere specifically at a hot spot,

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and this probe made the first in situ measurements and the only in situ measurements of Jupiter that exist today.

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So it's very important to understand how hot spot meteorology works,

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in order to place these in situ measurements from the Galileo probe in its proper context.

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In 2000 the Cassini spacecraft flew past Jupiter and created a series of still images

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that we compiled into time-lapse movies of Jupiter's atmosphere.

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Using these movies, we observed Rossby waves that caused north-south meanders in a jet stream south of the equator.

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With new movies we instead focused on hot spots.

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Hot spots are unique because we believe that there is a Rossby wave similar to what we previously detected,

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but instead of this Rossby wave moving north-south, it primarily moves up and down in the atmosphere.

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The downward portion of the wave pushes air down into warmer layers of the atmosphere.

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This causes any clouds that are embedded within the wave to evaporate and prevents further clouds from forming.

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So at any given time there are approximately eight to ten hot spots in Jupiter's atmosphere

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that are spaced roughly evenly apart from one another.

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We believe that each of the downward portions of this Rossby wave corresponds to the hot spots that we see on Jupiter.

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This new finding is exciting because it will allow us to re-examine the Galileo probe data,