L - Special topics in atmospheric sciences
John Lee Grenfell
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Photochemistry and Biosignatures of Atmospheres in the Solar System and Beyond
John Lee Grenfell, FU Berlin Winter Semester 2024
Whether life exists beyond the Earth is a question which has fascinated since the dawn of civilization. We are living in exciting times in which the central question “Are we alone?” can be scientifically investigated like never before thanks to ground-breaking space telescopes such as James Webb and planned missions like the Habitable Worlds Observatory and the Large Interferometer for Exoplanets (LIFE) missions. In this lecture course you will learn the basics of atmospheric biosignatures (signs of life) – how to recognize them, caveats to look out for (‘false friends’) and how to link theoretical model studies with observations. We will study examples of (rocky) planets both in and beyond the Solar System. The course will introduce the basic principles of atmospheric photochemistry and will deal with how this relates to atmospheric evolution and composition.The course will cover the evolution and modern-day states of Earth and it’s neighboring planets, Venus and Mars. We will discuss modern day atmospheric (potential) biosignatures on Earth (and Earthlike planets), including oxygen, ozone, methane, nitrous oxide and chloromethane as well as their spectral signals and detectability by modern instruments. Regarding Mars, we will discuss atmospheric methane and its photochemical sources and sinks. Regarding Venus, we will discuss phosphine and its stratospheric responses. We will additionally discuss the photochemistry of the gas and ice giants in the Solar System, then small bodies and moons, including the fascinating case of Titan. Finally, we will focus on rocky exoplanets beyond the Solar and study some emerging targets where first constraints of atmospheric composition are becoming available.
close16 Class schedule
Regular appointments