Young planets with teenage sun take the place of space studies

HANOVER, NH – February 12, 2021 – A newly discovered planetary system will allow researchers to study a growing group of planets, according to a study co-led by Dartmouth.

The new system, called TOI 451, is made up of at least three neighboring planets orbiting the same sun. The planets are spaced between Earth and Neptune.

According to the research team, NASA’s Hubble Space Telescope and its prospective agent, the James Webb Space Telescope, can be used to study the atmosphere of each planet. Such research could lead to information on the evolution of planetary systems such as our own solar system.

“The sun in this planetary system is very similar to our own sun, but much younger,” said Elisabeth Newton, a professor of physics and astronomy at Dartmouth who co-directs the research team. “By studying these planets in the context of others, we can build the picture of how planets shape and evolve.”

TOI 451 was found, published in the Astronomical Iris, began in 2019 through a revision of data from NASA’s Satellite Survey Transiting Exoplanet (TESS).

All three planets were discovered using data from TESS. Once the findings were made, follow-up work was carried out using NASA’s Spitzer Space Telescope, South Africa’s large ground-based telescope and other facilities. In total, more than 50 researchers representing dozens of institutions contributed to the research.

“The database from TESS is unparalleled for discovering these young planetary types,” said Andrew Mann, assistant professor at the University of North Carolina at Chapel Hill and co-director of research. “We are fortunate to be working at a time when we have access to data from such a successful exoplanet mission.”

The planets fill entire orbits around their sun on time intervals ranging from about two days to 16 days. The host star is similar in mass to the Earth’s sun, but much younger at just 120 million years old.

“The sun of the recently discovered planets is more like a teenager compared to our own sun. That means its planets are still changing and evolving,” Newton said.

Their star and planets are part of the stellar stream of Pisces-Eridanus, an association of young stars that spans much of the southern galactic hemisphere. The connection of the stars and their age was previously identified by individual teams using data from TESS and the European Space Agency’s Gaia spacecraft.

According to NASA, there are more than 4,000 known planets outside the solar system. Most of these planets are older and far further from Earth than the new system.

While most of the discoveries are single planets, other multi-planetary systems have been discovered before. Only seven other juvenile systems with multiple transmission planets have been discovered, according to the research team.

The discovery of multiple planets in the same system allows researchers to compare the evolution of individual bodies, knowing that they created and evolved around the same sun.

In addition to the planets, researchers have also found evidence of a disk of debris that is “dustier” but similar in other ways to the solar system’s own asteroid belt. In 2019, research group DS found Tuc Ab, an exoplanet orbiting one of the brightest known young stars.

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A full list of the entire research team can be found on the research paper.

Co-director of research Elisabeth Newton on Twitter: @EllieInSpace

For more Dartmouth science news on Twitter follow: @ dhirsch111