Haze Formation in Warm H2-rich Exoplanet Atmospheres

Understand

New observing capabilities coming online over the next few years will provide opportunities for characterization of exoplanet atmospheres.

• However, clouds/hazes could be present in the atmospheres of many exoplanets, muting the amplitude of spectral features.
• We use laboratory simulations to explore photochemical haze formation in H2-rich exoplanet atmospheres at 800 K with metallicity either 100 and 1000 times solar.
• We find that haze particles are produced in both simulated atmospheres with small particle size (20 to 140 nm) and relative low production rate (2.4 x 10-5 to 9.7 x 10-5 mg cm-3 h-1), but the particle size and production rate is dependent on the initial gas mixtures and the energy sources used in the simulation experiments.