Floating in a stream of young stars, astronomers have seen a trio of neighboring Earth-like planets orbiting a much younger version of our own sun.
The team found the young, hot worlds using observations from NASA’s Exoplanet Survey Satellite (TESS), according to a new study published in The Astronomical Journal. The planets orbit a star called TOI 451.
The system is located in a newly discovered stellar current Pisces-Eridanus, which is less than 3% the age of our solar system, which stretches over a third of the sky. These so-called star rivers form when the gravity of our galaxy, the Milky Way, breaks up groups of stars and dwarf galaxies, forming an elongated cluster that continues to disperse over time.
“This system checks a lot of boxes for astronomers,” lead researcher Elisabeth Newton said in a statement Friday. “It is only 120 million years old and only 400 light-years away, allowing detailed observations of this young planetary system. And because there are three planets between two and four times the size of Earth, they make promising goals for testing theories about how planetary atmospheres evolved. “
NASA’s Goddard Space Flight Center
Pisces-Eridanus, named after the constellations with the largest number of stars, covers 14 constellations in total – measuring about 1,300 light-years.
Astronomers have estimated that it is only 120 million years old – eight times younger than previous estimates. His young age makes him particularly interesting for studying the formation and evolution of the planet and stars.
The star of the system, TOI 451, also known as CD-38 1467, is in the constellation Eridanus, about 400 light-years away. It has 95% of the mass of our sun, but it is 12% smaller, slightly colder and emits 35% less energy.
TOI 451 rotates every 5.1 days – five times faster than the sun.
“The sun of the newly discovered planets is like a teenager compared to our own sun. That means its planets are changing and evolving,” Newton said.
NASA’s Goddard Space Flight Center
All three planets are very hot and inhospitable to life as we know it, orbiting their star three times closer than Mercury ever gets to our sun. Temperature estimates range from about 2,200 degrees Fahrenheit for the innermost planet to about 840 F for the outermost.
The nearest planet orbits the star about every 2 days, while the farthest circle orbits every 16 days. Their size varies between that of Earth and Neptune.
While there are over 4,000 known planets outside our solar system, most of them are older and farther from Earth than the newly discovered system. According to the research team, only seven other young systems with multiple planets in transit have ever been found.
The trio offers astronomers the rare opportunity to study a group of growing planets. Researchers plan to continue studying planets using NASA’s Hubble Space Telescope and its planned successor James Webb Space Telescope, to examine how systems like our solar system evolve.
“By studying these planets in the context of others, we can share the picture of how the planets form and develop,” Newton said.