While David Sing was finishing his doctorate, a colleague called him over one day to help work on images from the Hubble Space Telescope. It was his first close study of exoplanets, the distant planets beyond our own solar system. “I never looked back,” says Sing, who promptly switched the focus of his research.
Sing has joined Johns Hopkins University as a Bloomberg Distinguished Professor, is known as a foremost expert in exoplanets—a relatively young but endlessly vast field of astronomy and planetary science that probes into unknown reaches of the universe.
Since the first confirmation of an exoplanet in 1995, scientists have identified more than 3,700 orbiting around sun-like stars outside our solar system, ranging from gas giants and super-earths to terrestrial-sized planets. It’s believed there are trillions more, averaging at least one exoplanet for each star in our galaxy alone.
“These are completely new astrophysical bodies to study,” says Sing. “It’s very exciting because we have no idea what to expect and there are so many to study.”
And Sing himself has already contributed to breakthrough discoveries in the nascent field. Using advanced telescopes to observe these transiting planets, he and colleagues have detected features such as haze and stratospheres, and atmospheric compounds including sodium, potassium, water, helium, and hot-hydrogen gas.
The Hubble telescope has been particularly critical to Sing’s research and aided in his landmark 2015 comparative study of “hot Jupiters” across 10 different solar systems. He’s now heading up the largest Hubble research program on exoplanets, comparing 20 exoplanets across a range of wavelengths—from ultraviolet to infrared.
Sing’s new post at Johns Hopkins brings him closer to the Hubble, whose operations center is based in the nearby Space Telescope Science Institute. He expects to work closely with data from James Webb Telescope, which is set to launch into space in a few years.
Sing first honed in on exoplanets as a post-doc, at the University of Arizona and then the Institut d’Astrophysique de Paris. In 2010, he joined the University of Exeter, where he became an associate professor of astrophysics, working within its Extrasolar Planets Team.
Over time Sing has become known for his state-of-the-art observations of transits—when exoplanets pass in front of their host star—and eclipses. Both methods can yield a plethora of details on the planet’s composition, temperature, and atmospheric structure. With transits, he has developed a special interest in transmission spectroscopy, studying absorption signals within an exoplanet’s atmosphere.
Even before Sing devoted his career to outer space, it was a lifelong passion, he says. Growing up in Helena, Montana, he dreamed of being an astronaut. In high school, he worked out funds from his science club to build a telescope for viewing the Comet Shumaker-Levy’s collision with Jupiter. “I was hooked,” Sing says.
At the University of Arizona, Sing studied physics for his bachelor’s and doctorate degrees. At the time he was already connected to Johns Hopkins, using its FUSE satellite for his PhD thesis on binary star systems.