From his inaugural run at Palomar Observatory to leading the launch of a unique observing mode on its telescopes, Shreyas Vissapragada has forged new pathways in exoplanet research to determine the ways planets live out their lives. Shreyas applies an innovative method called ultranarrowband photometry to examine exoplanets by taking highly precise measurements of helium in their outflowing atmospheres. The custom filter he designed and commissioned at Palomar Observatory allows for efficient inspections of gas-giant exoplanets and has yielded fresh insights into their stability against atmospheric loss.

In his fellowship, Shreyas will pursue a two-pronged approach to understand how exoplanet atmospheres evolve over time. He will start by implementing the largest yet survey of escaping atmospheres focused on planets in and near the “Neptune desert,” a missing population of sub-Saturn-sized planets orbiting close to their host stars. Next, Shreyas will develop new techniques to observe the escaping atmospheres of smaller planets. His meaningful analysis of diverse targets will help refine theories of planet formation, evolution, and potentially habitability. Shreyas will receive a Ph.D. in planetary science from the California Institute of Technology in Summer 2022.

“When [former 51 Pegasi b Fellow] Jessica Spake discovered helium in the outflow of a planet’s atmosphere, I found that captivating. I designed an observational technique to build on her approach, look at a broad sample of planets, and scope in on the question of how they change over time.”