Johanna K. Teske
Origins/Hubble Postdoctoral Fellow

Johanna Teske

Research Interests

Exoplanet host star elemental abundances as probes of planetary system composition; small planets around "solar twin" stars; astronomical instrumentation; exoplanet host star binarity as characterized by speckle imaging and spectroscopy


B.S., Physics, American University, 2008 M.S., Astronomy, University of Arizona, Tucson, 2010 Ph.D., Astronomy, University of Arizona, Tucson, 2014

Contact & Links

  • (202) 478-4885 | fax: (202) 478-8821
  • jteske at
  • Earth and Planets Laboratory
    Carnegie Institution for Science
    5241 Broad Branch Road, NW
    Washington, DC 20015-1305
  • Curriculum Vitae
  • Publications
  • Personal Website


Johanna Teske
Johanna (left) and instrument scientist Dan Kiminki (right) mounting the MMT Advanced Echelle Spectrograph (MAESTRO), a high resolution optical spectrograph built at the University of Arizona, to the 6.5m Multiple Mirror Telescope (MMT).
Johanna Teske's research focuses on measuring the abundances of different elements in exoplanet host stars in order to learn about the starting chemical conditions for planet formation. She uses high resolution optical spectrometers mounted on big telescopes in Hawaii and Chile to collect her data; observing and tinkering with these instruments is her favorite part of her job. 

In particular, Johanna is interested in the influence of host star composition on resulting planet composition -- how are stars chemically connected to their planets? She is investigating this from several different angles, including comparing C/O ratios estimated in transiting hot Jupiter exoplanet atmospheres to those measured in their host stars, searching for evidence of "missing" terrestrial planet building elements in the stars that are known to host small planets, and comparing estimates of transiting cool Jupiter exoplanet interior compositions to their host star abundances. She is also excited to work with the Carnegie PFS team to chemically characterize the stars around which they are searching for planets via RV. 

Very recently Johanna joined the Differential Speckle Survey Instrument (DSSI) team, who use DSSI on medium to large telescopes (Gemini, DCT, WIYN) to detect close-in companions to exoplanet (or exoplanet candidate) host stars. DSSI provides simultaneous diffraction-limited optical imaging (FWHM~0.02" at 650nm) in 2 channels and has observed almost 1000 Kepler Objects of Interest (KOIs) to help verify their planet-hosting nature. The DSSI team is now coupling with AO and spectroscopy observations to better characterize the binarity fraction, period distribution, mass ratios, and planet properties of host stars.