Elisabeth Newton, Berkeley High School alumna and assistant professor of physics and astronomy at Dartmouth College, led a research team that discovered a planet located outside Earth’s solar system, as first reported by Berkeleyside.
The planet, named DS Tuc A b, was first detected by NASA Transiting Exoplanet Survey Satellite, or TESS, which observed changes in the brightness of the star it orbits around — its host star — as DS Tuc A b passed in front of it. Associate professor at Dartmouth College Ryan Hickox said in an email that Newton’s research team was able to confirm the planet’s existence by compiling data from spectroscopic observations from telescopes and observatories, such as Southern Astrophysical Research Telescope, Southern African Large Telescope and Spitzer Space Telescope.
Newton said she is excited about DS Tuc A b’s discovery because it could help give a better understanding of what happens to planetary atmospheres when subjected to heat and radiation from their host stars. DS Tuc A b is also believed to be gradually shrinking through a process called photoevaporation, during which radiation from the host star drives off the atmosphere of a planet.
“The planet provides an important data point in our growing collection of well-characterized planets,” Hickox said in the email. “It is also interesting because it is so young; it is likely currently still in the process of forming and will possibly contract further and lose some mass as it settles down to its final mass and size.”
According to Newton, DS Tuc A b is intermediate in size and is in between the size of Neptune and Saturn. The planet also has an eight-day orbital period, meaning that one year on the planet lasts just over a week. The planet is believed to have a gaseous envelope such as that of Neptune or Saturn.
DS Tuc A b is one of the very few planets that orbit around young stars. Its host star formed merely 45 million years ago, which is very short by astronomical standards, according to Hickox.
“The reason we are looking for planets around young stars is that it provides a snapshot of the planetary evolution process,” Newton said. “Formation and evolution take millions to tens or hundreds of millions of years, and so we can’t — as humans — observe that in action, so instead we have to look at pictures.”
According to Hickox, there will be many opportunities to continue to learn about this planet using future observations collected with NASA’s upcoming James Webb Space Telescope, which could allow a detailed characterization of the planet’s atmosphere.
Newton described her experience of discovering DS Tuc A b as fun and gratifying.
“I got to work with a lot of different scientists across the U.S. and around the world, which I haven’t really been able to do before,” Newton said. “So I really enjoyed working with them, and everyone I worked with was super fun and really supportive.”