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Robert J. Trumpler Award

For a recent PhD thesis considered unusually important to astronomy

The Robert J. Trumpler Award is given each year to a recent recipient of the PhD degree in North America whose research is considered unusually important to astronomy.

The recipient of the 2018 Trumpler Award is Benjamin J. Fulton, a staff scientist at NExScI, CalTech.

The Astronomical Society of the Pacific (ASP) is proud to award the 2018 Robert J. Trumpler Award to Dr. Benjamin J. (“BJ”) Fulton, a staff scientist at NExScI, based at IPAC, a science and data center for astronomy at Caltech. Dr. Fulton’s landmark doctoral dissertation focused on the discovery and categorization of extrasolar planets, and in particular smaller planets between the sizes of Earth and Neptune.  

During Fulton’s graduate studies at the University of Hawaii’s Institute for Astronomy, he analyzed data from the W. M. Keck Observatory for over 1,300 planets that were initially discovered by NASA’s Kepler space telescope. The primary result of Fulton’s thesis, under the advisement of Prof. Andrew Howard, is the discovery that the size distribution of extrasolar planets has a gap separating two types: super-Earths with sizes smaller than about 1.5 Earth diameters and sub-Neptunes with sizes 2-3 Earth diameters. The interpretation of this gap is that it represents the separation of rocky planets from low-mass planets with gas atmospheres, and its discovery has already sparked numerous theoretical and observational studies. BJ’s paper announcing this gap garnered immediate attention. A measure of how important this effect is on the field is that it has been given a name, “The Fulton Gap.”

As one of his nominators stated, the Fulton Gap “will undoubtedly be in undergraduate and graduate textbooks. It demonstrates a natural division among planets, on par with the division between rocky planets, ice giants, and gas giants in our Solar System." Fulton now serves as the deputy project scientist for the NASA-National Science Foundation Exoplanet Observational Research (NN-EXPLORE) program, which funds and operates the NEID spectrograph, an instrument with the ability to discover Earth-like planets orbiting the nearest stars.

Please contact the Awards team if you have questions about the nomination process