Eric L. N. Jensen
Professor of Astronomy; Chair, Division of Natural Sciences & Engineering
|HK Tau velocity data from ALMA (Jensen & Akeson 2014, Nature)||HK Tau, artist's conception (©2014 Robert Hurt)|
I'm a Professor of Astronomy in the Physics and Astronomy Department at Swarthmore College. I also teach about climate change in Swarthmore's Environmental Studies program. I am chair of Swarthmore's Natural Science & Engineering Division, and former Director of the Frank Aydelotte Foundation for the Advancement of the Liberal Arts (current CV).
My research interest, broadly speaking, is understanding extrasolar planets, planets that orbit other stars. I'm also interested in astrobiology, the study of the origin and distribution of life in the cosmos.
I work with NASA's Transiting Exoplanet Survey Satellite (TESS) mission, which surveys the sky for planets by detecting small eclipses that occur when planets pass in front of their host stars. I wrote and maintain the web interface that allows us to plan followup observations of planet candidates, and also software that allows us to automatically schedule and carry out exoplanet observations with the LCO telescope network. I was a member of the KELT ground-based transit survey, which discovered KELT-9b, the hottest known exoplanet. That discovery was aided in part by observations with the Peter van de Kamp Observatory here at Swarthmore.
Another of my interests is planet formation in binary star systems, and whether such planets would be habitable. Since more than half of all stars are members of binary systems, understanding how often planets form in binaries is important for understanding the frequency of planet formation in the universe and the likelihood of life outside our solar system. One project related to this topic involves observations of protoplanetary disks around HK Tau, a young binary system where we can see that the two protoplanetary disks around the stars are significantly misaligned with each other (see images above, our paper in Nature, and the National Geographic story). This means that any planets that form in this system will likely have orbits that oscillate in inclination and eccentricity due to the influence of the binary companion star.
I have appeared on WHYY's Radio Times, discussing the rendezvous of the Juno spacecraft with Jupiter, the discovery of the TRAPPIST-1 planetary system, and the first images from the James Webb Space Telescope.
I appear regularly on KYW Newsradio to talk about astronomical topics in the news, such as whether an asteroid could destroy Earth, observations of Venus's atmosphere and what they might mean for the possibility of life there, the landing of the Perseverance rover on Mars, and the deflection of an asteroid by NASA's DART mission.
I gave a public talk about my research on exoplanets and their oddly tilted orbits to the New Jersey Astronomical Group.
I'm interested in life beyond Earth, and along with my colleague Amy Cheng Vollmer, Professor emerita of Biology, I've given some talks about some basic astrobiology concepts. Here's a lecture we gave on this topic.
I now do all of my grading / student feedback with a paperless workflow, using an iPad; here is a screencast explaining how that works. (It is based on using Notability and Moodle, but the basic approach should work for other learning management systems, too.)
Increasingly, I've been using Moodle as the course web page for courses I'm teaching. One downside of that is the difficulty of linking to those courses so that people other than the students can see what I'm doing. Below are listings of courses I regularly teach; if you are an educator, please don't hesitate to email me and I'd be happy to share course materials from any of these.
Comments or suggestions to Eric Jensen,
Last modified June 2023