What is the modern search method that analyzes starlight filtering through an exoplanet's atmosphere when it passes in front of its star?

Answer

Transit spectroscopy.

Transit spectroscopy is the technique used when an exoplanet moves in front of its host star; scientists analyze the small fraction of starlight that filters through the planet's atmosphere to identify chemical absorption lines.

What is the modern search method that analyzes starlight filtering through an exoplanet's atmosphere when it passes in front of its star?
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