Johanna K. Teske
Staff Scientist

Research Interests

Exoplanet interior, atmospheric, and host star composition; high resolution spectroscopy; precision radial velocity exoplanet mass measurements; stellar jitter/activity; interdisciplinary studies of exoplanet diversity; binary exoplanet host stars (imaging, spectroscopy); astronomical instrumentation.


University of Arizona, Department of Astronomy/Steward Observatory, Ph.D., May 2014
American University, Department of Physics, B.S., May 2008

Contact & Links


Artist's conception of HD 21749c, the first Earth-sized planet found by NASA's Transiting Exoplanets Survey Satellite (TESS), as well as its sibling, HD 21749b, a warm sub-Neptune-sized world. These planets were characterized by the Planet Finder Spectrograph by a team including Johanna. Illustration by Robin Dienel, courtesy of the Carnegie Institution for Science.
Johanna Teske's research interests focuse on quantifying the diversity of exoplanet compositions and understanding the origin of that diversity. She pursues these goals by combining observations of exoplanet masses, radii, atmospheres, and host stars. She also prioritizes community-building and working to make astronomy more inclusive and equitable. 
Currently, Johanna leads one of the largest and the first statistically-motivated surveys (the Magellan-TESS Survey, MTS) to measure the densities, system architectures, and precise host star abundances of small transiting planets. The MTS will build a statistical sample that accounts for biases in target selection and in radial velocity observations to robustly address the question, Do super-Earth and sub-Neptune planets form along the same or different pathways? Given the prevalence of these planets and their absence (so far) in the Solar System, there is great interest in understanding how they formed and, at the smaller radius end, how "Earth-like" they may be. She is also participating in or leading several large HST and JWST proposals to measure the compositions of super-Earth and sub-Neptune planet atmospheres. These efforts will produce the largest collection of small planet atmospheres to date, facilitating tests of formation scenarios and demographic studies of atmospheric metallicity and the presence of clouds/hazes over a range of equilibrium temperatures, surface gravities, and host star types. She also plans to collaborate with other Carnegie EPL scientists to guide the scope of new high pressure-temperature experiments to more accurately interpret exoplanet densities.
Johanna is a member of the Planet Finder Spectrograph (PFS) team and leads and manages the PFS observing queue within the Magellan consortium, making possible a wide variety of exoplanet science. She has also led research that touches on many aspects of exoplanet science – surveying protoplanetary disk chemistry, measuring transiting exoplanet atmospheres and masses, determining detailed host star compositions, and helping build and maintain high-resolution instruments for large telescopes. In addition, Johanna started and runs the blog Las Campanas Belles, which highlights the experiences of women working at Las Campanas Observatory in Chile. She is always looking for guest writers! 

Before joining EPL as a Staff Scientist, Johanna Teske held the first Carnegie Origins Postdoctoral Fellowship, followed by a NASA Hubble Postdoctoral Fellowship at Carnegie.