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Astronomy

detectionandcharacterizationofexoplanetatmospheresthroughtransmissionspectroscopy

Quick fact

The first detection of an exoplanet atmosphere was made in 2001 when sodium was found in the atmosphere of HD 209458b, a hot Jupiter – using transmission spectroscopy.

Why this is interesting

Imagine knowing the recipe of a cake by looking at the shadow it casts. That's exactly how astronomers figure out what's in the atmosphere of a planet trillions of miles away.