Brendan P. Bowler


Caltech Joint Center for Planetary Astronomy Postdoctoral Fellow

I’m a JCPA Prize Postdoctoral Fellow in the Division of Geological and Planetary Sciences at the California Institute of Technology.  I study the formation and atmospheric properties of extrasolar planets through high contrast direct imaging and spectroscopy.  I primarily use large-aperture (8-10 meter) telescopes equipped with adaptive optics systems like the Keck, Gemini, and Subaru telescopes. 

Prior to Caltech I was a graduate student at the University of Hawaii’s Institute for Astronomy.

Contact Information:

Email: bpbowler [at]

Office: 169D South Mudd

Phone: (626) 395-8552

Address:  California Institute of Technology

                   Division of Geological and Planetary Sciences

                   1200 E California Blvd MC 150-21

                   Pasadena, CA 91125

  1. December 2014: I’ve added a new page to this site with my published data from recent papers.  I’ll continue to add more spectra over the next few weeks.  Meanwhile, feel free to contact me if you’d like any other data or have questions.

  1. December 2014: K2 found its first planet!  Andrew Vanderburg presented HIP 116454 b, a new super-Earth with a radius of 2.5 R_Earth found by the repurposed Kepler space telescope (  Deep adaptive optics images of the system that I acquired at Keck showed that the primary is single and there are no nearby background stars, which can cause source confusion on the large Kepler pixels.

  1. November 2014: Our new paper presenting the statistical results from PALMS was accepted to ApJS.  Giant planets are rare in the outskirts of M dwarf planetary systems; we show that at most 6% of M dwarfs harbor massive planets like those orbiting HR 8799 and b Pic.  The paper can be found here:

  1. April 2014: I received the 2014 Trumpler Award from the Astronomical Society of the Pacific for a Ph.D. thesis in North America considered “unusually important to astronomy.”  It’s a big honor to join such a prominent list of previous recipients. 

  1. April 2014: The last few months have been filled with productive visits to other universities to coordinate proposals, upcoming papers, and give talks.  Thanks to my colleagues and collaborators at UCLA, the CfA, Steward Observatory, UT Austin, UC Berkeley, UCI, and UCSD for the warm welcome.  These visits gave me a lot of food for thought and good ideas for upcoming research.

  1. January 2014: Our new paper presenting follow-up spectroscopy of the planetary-mass companions ROXs 42B b and FW Tau b was accepted to ApJ:  ROXs42B b shows clear signs of low gravity, but FW Tau b is enigmatic and might be a wide planetary-mass companion or a brown dwarf with an edge-on disk... we need more data!

  1. December 2013: Observing runs at Cerro Pachon (SOAR) and Kitt Peak (Mayall) as part of a reconnaissance program to identify new young M dwarfs for my direct imaging planet search.  Based on the current census, we’ve only skimmed the surface of YMG members.

  1. December 2013: I joined the Palomar Ultraviolet Laser for the Study of Exoplanets (PULSE) team as Project Scientist.  Led by Richard Dekany (Caltech) and Christoph Baranec (UH), PULSE is a proposed LGS upgrade to the Palomar P3000 AO system.  The instrument is based on the successful Robo-AO unit on P60 and incorporates a UV laser that operates by Rayleigh scattering.  If approved, PULSE will extend AO imaging capabilities at Palomar from V~10 to V~16 mag with NIR Strehls above 60%, opening up direct imaging planet searches at the 5-meter telescope to the most abundant stars-- M dwarfs.  See the PULSE website and paper for more information and updates.

  1. In the fall of 2013 I finished my PhD at the IfA and moved from Hawaii to California to start a new JCPA fellowship at Caltech.  You can read up on the new Joint Center for Planetary Astronomy here: .

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