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Over the last 4.5 billion years, the Sun has shaped every planet in our solar system.

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Each planet is connected to the Sun through an invisible web: the Sun's magnetic field.

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Though every planet experiences the Sun's magnetism...They do so from very different distances.

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How does the Sun's impact change across space?

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There's one planet giving us clues.

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So Mercury is special not just because it's the closest planet

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to the Sun but also because the distance it is

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from the Sun varies more than any other planet in our solar system.

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Mercury actually has a very oval-shaped orbit compared to the rest.

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Mercury is a natural laboratory for running experiments.

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We can observe the planet's surroundings as it gets closer and farther away from the Sun

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and see what changes.

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Norberto and Gina looked to Mercury with a question:

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How does the Sun's impact change throughout Mercury's orbit?

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A stream of particles races out from the Sun into space. Scientists call it the solar wind.

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But Mercury has a shield - the planet's magnetosphere slows and deflects the solar wind.

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When solar wind particles bounce off this magnetospheric boundary,

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they generate low-frequency waves.

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They're like ripples traveling upstream in the solar wind.

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Using data from NASA's MESSENGER mission, Norberto and Gina watched these waves change throughout Mercury's orbit.

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The farther Mercury was from the Sun...The more waves MESSENGER detected.

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Farther from the Sun, the Sun's magnetic field is weaker.

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We found that this is the key parameter 
that allows more waves to be generated.

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The solar wind ultimately pushes the waves back towards Mercury where they add energy to its surroundings.

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Although Mercury doesn't have an atmosphere these waves occur at other planets that do: Venus, Mars, Earth.

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In the long run, the energy from these waves can change a planet's atmosphere in ways we're still trying to understand.

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Mercury's waves help us understand how planets interact with stars including those beyond our solar system.

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This is something we could only have measured with Mercury,

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thanks to how close it is to the Sun