Profile of exoplanet professor John Johnson

An exoplanet hunter joins the faculty

John Asher Johnson

John Asher Johnson, his wife, Erin Johnson, and their young sons Owen and Marcus meandered by car from Caltech to Cambridgeport last summer—a mere flick of an eye for the new professor of astronomy, who studies exoplanets, light years away. (Some 800 exoplanets are known, as many are being confirmed, and there are thought to be billions to trillions.) An enthusiastic teacher, Johnson outlines his field using the “Exoplanets Explained” video, in the PhD TV series on YouTube: the voices are his and his graduate students’, happily distinguishing Doppler-effect, radial-velocity planet detection from direct imaging, star transits, gravitational microlensing, and other techniques. All are in use at Harvard’s exoplanet research group, which he calls “unique in astronomy.” At Caltech, he was the team; here, colleagues include professors David Charbonneau (in whose office Johnson is camping out during a sabbatical year) and Dimitar Sasselov, lecturer David Latham, and others. Because Harvard teaching opportunities are innovative and diverse, he says, in Cambridge, “I can be a university professor in the fullest sense,” building on the nonhierarchical ethos he established at his “ExoLab” in Pasedena. When he is not playing basketball, bicycling, building Legos with the boys, or preparing to teach the introductory stellar and planetary astronomy course this spring, Johnson thinks about deploying future observational instruments on Earth and in orbit. He aims for “unambiguous detection of life signatures outside our solar system within our lifetimes.” Unlike other astronomical objects, he has written, planets “inspire a subtle emotional curiosity…because they alone can be thought of as places, not things.”

Related topics

You might also like

Harvard Professor Michael Sandel Wins Philosophy’s Berggruen Prize

The creator of the popular ‘Justice’ course receives a $1 million award.

Harvard Economist Wolfram Schlenker Is Tackling Climate Change

How extreme heat affects our land—and our food supply 

In Sermon, Garber Urges Harvard Community to ‘Defend and Protect’ Institutions

Harvard’s president uses traditional Memorial Church address to encourage divergent views.

Most popular

What Trump Means for John Roberts's Legacy

Executive power is on the docket at the Supreme Court.

Harvard’s Endowment, Donations Rise—but the University Runs a Deficit

The annual financial report signals severe challenges to come.

How MAGA Went Mainstream at Harvard

Trump, TikTok, and the pandemic are reshaping Gen Z politics.

Explore More From Current Issue

A person walks across a street lined with historic buildings and a clock tower in the background.

Harvard In the News

A legal victory against Trump, hazing in the Harvard-Radcliffe Orchestra, and kicking off a Crimson football season with style

Two small cast iron pans with berry-topped desserts, dusted with powdered sugar, alongside lemon slices.

Shopping for New England-made gifts this Holiday Season

Ways to support regional artists, designers, and manufacturers 

A man in a gray suit sits confidently in a vintage armchair, holding a glass.

The Life of a Harvard Spy

Richard Skeffington Welch’s illustrious—and clandestine—career in the CIA