![Jared Siegel, an undergraduate student at UChicago, spent six months finding a way to uncover new information from data extracted by NASA's Kepler space telescope, which searched for planets around distant stars. Credit: NASA/Ames Research Center/W. Stenzel/D. Rutter Student uses NASA data to reveal new details about planets in other solar systems](https://oponame.com/wp-content/uploads/2022/10/Student-uses-NASA-data-to-reveal-new-details-about-planets.jpg)
Jared Siegel, an undergraduate student at UChicago, spent six months finding a way to uncover new information from data extracted by NASA’s Kepler space telescope, which searched for planets around distant stars. Credit: NASA/Ames Research Center/W. Stenzel/D. Rutter
In recent decades, the number of known exoplanets – planets in other solar systems – has exploded. But we are still in the dark about a number of details, including their mass and composition.
A University of Chicago undergraduate, however, was able to pick up some clues from data that most scientists had overlooked.
Jared Siegel, BS ’22, spent six months analyzing data taken by a NASA spacecraft. Some of this data was full of statistical noise, making it difficult to differentiate planets from other phenomena; but Siegel and his adviser, astrophysicist Leslie Rogers, were able to extract useful information about these planets, setting an upper limit on their mass.
“As the results took shape, they got more and more exciting,” said Siegel, who graduated this spring.
The research results for Siegel’s undergraduate thesis have been published in The Astronomical Journal.
Disturbances of the planet
Siegel and Rogers combed through data from a NASA space telescope called Kepler, which spent nine years tracking tiny bursts of light from distant stars. These blips can occur when a planet passes in front of the star, temporarily dimming its light.
Many scientists had already analyzed this data, finding evidence for more than 2,600 exoplanets. But Siegel and Rogers wondered if there was a way to use statistical methods to extract even more information.
Their approach relied on the fact that the Kepler telescope found many stars that appear to have multiple planets around them, much like Earth and its sister planets around the sun. The gravity tug of these planets will alter each other’s orbits slightly, compared to how they would move if there was only one planet around a star. The more massive the planets, the stronger these disturbances.
Siegel and Rogers thought they could use this fact to say something about the masses of certain planets.
“If we know there are multiple planets in a system but we don’t see large perturbations in transit times, we know the planets can’t be particularly massive,” Siegel explained. “For example, we could say they’re probably not Jupiter-mass, because then they’d be pulling on each other noticeably.”
They applied this logic to a sample of 170 planets in 80 different star systems. For about 50 of these planets, they were able to set an upper limit on the mass of the planet.
This is useful, the scientists explained, because they can begin to rule out options for the composition of the planet. “For example, you can say, ‘Well, this planet is too light to be made of pure iron,'” Siegel said. “For more than twenty planets, we can say ‘this planet is too light to be made of Earth-like material.'”
This information also helps scientists better understand the entire population of exoplanets. “We really want to know how many planets in a given mass range are likely to be rocky, or water worlds, or gaseous planets,” Rogers said.
Nonlinear paths
The study’s biggest challenge was accounting for noise in the data, the scientists said.
“A lot of these stars are very faint and very distant,” Siegel explained. “It can be difficult to disentangle the signal from the planet itself – there’s a ton of noise from stars having flares or sunspots, or instrumental issues. Maybe the whole system is on a slope relative to us. You have to take all of those possibilities into account, so we spent a lot of time thinking about how the data might be messy.”
It was a rewarding experience for Siegel, who began doing research with faculty scientists during the winter of his freshman year at the University, but was not yet at the helm.
“I think, especially as an undergrad, there’s always this desire to find the answer in the back of the textbook. But with that kind of research, you can’t,” Siegel said. “But eventually, as it became more evident that this group of stars could help inform our understanding of the wider rest of the population, it became more and more exciting.”
“It’s very rewarding as a counselor to watch a student work down the nonlinear path to find an interesting problem to work on and ultimately make a new contribution to characterizing planets,” Rogers said.
Siegel is now studying astronomy as a freshman graduate student at Princeton, where he is a researcher at the National Science Foundation.
Astronomy student discovers 17 new planets, including an Earth-sized world
Jared C. Siegel et al, Mass Upper Bounds for Over 50 Kepler Planets Using Low-S/N Transit Timing Variations, The Astronomical Journal (2022). DOI: 10.3847/1538-3881/ac8985
Provided by the University of Chicago
Quote: Student uses NASA data to reveal new details about planets in other solar systems (2022, October 24) Retrieved October 24, 2022 from https://phys.org/news/2022-10-student- nasa-reveal-planets-solar. html
This document is subject to copyright. Except for fair use for purposes of private study or research, no part may be reproduced without written permission. The content is provided for information only.
#Student #NASA #data #reveal #details #planets #solar #systems