Floating in a stream of young stars, astronomers have seen three neighboring planets similar to Earth orbiting a much younger version of our own sun.
The team found the young, hot worlds using observations from NASA’s Transiting Exoplanet Survey Satellite (TESS), according to a new study in The Astronomical Journal. The planets orbit a star called TOI 451.
The system resides in a newly discovered Stellar Stream of Pisces-Eridanus, which is less than 3% older than our solar system and spans a third of the sky. These so-called rivers of stars are created when the gravity of our galaxy, the Milky Way, rips apart clusters of stars and dwarf galaxies, forming an elongated grouping that continues to spread in a stream 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 for detailed observations of this young planetary system. And because there are three planets between two and four times the size of Earth, they are very promising targets for testing. theories of how a planet’s atmosphere evolves. “
NASA’s Goddard Space Flight Center
Named for the constellations with the highest number of stars, Pisces Eridanus spans 14 constellations in total – measuring approximately 1,300 light-years.
Astronomers have determined that it is only 120 million years old – eight times younger than previous estimates. Due to its young age, it is particularly exciting for studying planet and star formation and evolution.
The star of the system, TOI 451, also known as CD-38 1467, is located in the constellation Eridanusabout 400 light years away. It has 95% of the mass of our sun, but it is 12% smaller, slightly colder and gives off 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 still changing and evolving,” said Newton.
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 inner planet to about 840 F for the outer.
The closest planet orbits the star about every 2 days, while the farthest orbits the star about every 16 days. They vary in size between Earth and Neptune.
While there are more than 4,000 known planets outside of our solar system, most of them are older and much further from Earth than the newly discovered system. Only seven other young systems with multiple continuous planets have ever been found, according to the research team.
The trio gives astronomers the rare opportunity to study a group of growing planets. Researchers plan to continue to study the planets using NASA’s Hubble Space Telescope and its planned successor, the James Webb space telescope, to investigate how systems such as our own solar system evolve.
“By studying these planets in the context of others, we can construct the picture of how planets form and develop,” said Newton.