Astronomers discover three young planets orbiting a youthful sun in a river of stars
Floating in a stream of young stars, astronomers have discovered a trio of neighboring planets that are similar to Earth and orbit a much younger version of our own sun.
The team found the young, hot worlds based on observations from NASA’s Transiting Exoplanet Survey Satellite (), according to a new study in the Astronomical Journal. The planets orbit a star called TOI 451.
The system resides in a newly discovered Pisces-Eridanus stellar stream, less than 3% the age of our solar system and stretching over a third of the sky. These so-called rivers of stars form when the gravity of our galaxy, the Milky Way, rips clusters of stars and dwarf galaxies, forming an elongated grouping that continues to disperse in a stream over time.
“This system checks many boxes for astronomers,” said lead researcher Elisabeth Newton in one Statement Friday. “It’s only 120 million years old and only 400 light-years away, which allows detailed observations of this young planetary system. And since there are three planets between two and four times the size of the earth, they are particularly promising targets for testing theories about how planetary atmospheres are made function develop. “
The Pisces Eridanus, named after the constellations with the highest number of stars, extends over a total of 14 constellations – with a length of about 1,300 light years.
Astronomers have determined that it is only 120 million years old – eight times younger than previously thought. Its young age makes it particularly exciting for studying planet and star formation and evolution.
The star of the system, TOI 451, also known as CD-38 1467, is in the, about 400 light years away. It has 95% of the sun’s mass, but is 12% smaller, a little 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 their planets are still changing and evolving,” Newton said.
All three planets are very hot and inhospitable to life as we know it, and orbit 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 closest planet orbits the star approximately every 2 days, while the farthest orbits approximately every 16 days. Their size is between that of Earth and Neptune.
While there are over 4,000 known planets outside of our solar system, most are older and much farther from Earth than the newly discovered system. According to the research team, only seven other young systems with multiple transit planets have so far been found.
The trio offers astronomers a rare opportunity to study a group of growing planets. The researchers plan to use NASA’s Hubble Space Telescope and its planned successor, theto study how systems like our own solar system evolve.
“By examining these planets in the context of others, we can piece together the picture of how planets form and evolve,” Newton said.