Eric Agol

Research Interests

Eric Agol creates theoretical models applied to extrasolar planet systems, as well as compact objects, binary stars, and gravitational lensing.


Faculty advisor for the Pre-Major in Astronomy Program (Pre-MAP).

Graduate students


Link to published paper on a Differentiable N-body Integrator published in Monthly Notices of the Royal Astronomical Society - with David Hernandez and Zach Langford

Precise constraints on the TRAPPIST-1 planets (Jan 21, 2021)

See the open access paper in the right here, and a University of Washington press release here.

Former Undergraduate, Graduate students and Postdocs:

Old News:

Image of Black Hole Shadow (April 2019). The Event Horizon Telescope (EHT) captured a radio image of the synchrotron emission surrounding the black hole in the Messier 87 Galaxy, realizing an idea we worked out 20+ years ago which inspired the EHT (Falcke, Melia & Agol 2000)

Hundreds of new planet candidates found in Kepler data

Period of seventh planet in Trappist-1 found with K2.

Link to paper.

TRAPPIST-1 hosts seven Earth-sized planets, three temperate.

Website dedicated to TRAPPIST-1

Figure 1 from the paper:

• We (Tiffany Jansen, Brianna Lacy, Ty Robinson and Vikki Meadows) proposed a new approach to detecting exomoons with the future 'High-Definition Space Telescope' using the astrometric offset between wavelengths dominated by a planet versus wavelengths dominated by its moon. See astrobites for a summary by Michael Zevin.

• Joint IAS/Princeton astrophysics colloquium in Fall 2015, which is recorded here.

• Quoted in a New York Times article on the Event Horizon Telescope

• Talk on April 30, 2014 on 'The Habitability of White Dwarfs' at the conference `Habitable Worlds Across Time and Space' at the Space Telescope Science Institute in Baltimore, MD. Here is a webcast of the talk.


• Graduate student Ethan Kruse found the first `self-lensing' binary star with the Kepler spacecraft. In 2003 I predicted this should be found with Kepler, at the same time as Sahu & Gilliland, although self-lensing binaries were mentioned as early as 1969 by Trimble & Thorne, 1971 by Leibovitz & Hube, and 1973 by André Maeder. The system is composed of a white dwarf and sun-like star. He explains the find here. Here is an image I made showing what this system might look like up close (with a real image of the Sun taken by the NASA SDO/HMI spacecraft as a proxy for theG dwarf companion to the white dwarf): Here is a preprint, and here is the supplementary online material.

And here is a movie that shows what the gravitational lensing effect might look like in this system (elapsed time in movie is about five hours): White dwarf lensing G dwarf.

• Here is a description of our discovery of a planet system with seven transiting planets: Discovery of seven planet system, and confirmation of more than 700 planets.

• Kepler-62f: the first potentially rocky, "habitable-zone" exoplanet found with Kepler.

The second-smallest diameter confirmed "habitable-zone" planet, 1.4 times Earth, was found by me, and confirmed by a large team of scientists using the Kepler spacecraft, Kepler-62f

The discovery was announced in May, 2013 in Science magazine: Borucki, Agol et al., 2013, Science. Astronomers (and astrobiologists) are excited about this find, and its possible implications for exo-biology.

• Here is a description of the first multi-planet system orbiting two stars that we just found: Kepler-47

• Here is a graphic depicting more than two dozen planets that I helped to confirm, led by my former PhD student, Jason Steffen:

41 New Planets confirmed with the Kepler Spacecraft

• We discovered two planets that orbit closest to one another of any planets found to date, Kepler-36:

Find out all about the closest known pair of planets in orbit around another star, in this infographic.

• Here is a news article about a secondary eclipse map of exoplanet HD 189733b:
Astronomers have made a crude two-dimensional thermal map of an extrasolar world they cannot yet see, confirming that violent winds rapidly whip around the planet

• I proposed in 2011 that 'habitable' planets might be found orbiting white dwarf stars:

• With my collaborators, I have:

  • First proposed with Heino Falcke and Fulvio Melia that radio VLBI could be used to see the shadow of the black hole at the center of the Milky Way Galaxy. See article in the New York Times and Science Magazine.
  • Modelled black hole accretion disks with the goal of explaining the spectra and variability of active galaxies. Download model atmospheres here!
  • Developed a technique for imaging quasars on very fine scales using gravitational lensing.
  • Pointed out how to find isolated black holes and white dwarfs in binaries in our own galaxy using gravitational microlensing and X-ray surveys.
  • Made multi-wavelength observations of the gravitational lens known as the 'Einstein Cross'.
  • Made polarimetric and infrared measurements of a T-Tauri star which eclipses once every 48 days.
  • Developed computer code for modeling transiting extrasolar planets.
  • Proposed using timing of transits to search for low-mass planets.
  • He has been probing weather on extrasolar planets by measuring the phases of extrasolar planets throughout their orbits using the Spitzer Space telescope. With graduate student Nick Cowan, he used this data to create the first crude 'map' of extrasolar planet HD 189733 B, as well as create an "alien map" of planet Earth using the EPOXI satellite looking back at Planet Earth, as described here.
  • Here is a radio interview on KUOW. Look at Research to learn more.


Office: B370 Physics and Astronomy Building
3910 15th Avenue NE
Seattle, WA 98105
Phone: (206) 543-7106
FAX: (206) 685-0403
Email: agol AT
Mail: Astronomy Department
Box 351580
University of Washington
Seattle, WA 98195