TESS Discovers A Trio Of Planets Orbiting A Young Sun-Like Star

NASA's Transiting Exoplanet Survey Satellite, known as TESS, is the perfect tool for the job when it comes to discovering distant exoplanets and new solar systems. An international team of astronomers recently announced the discovery of three hot planets that are larger than Earth orbiting a star that's a much younger version of the Sun called TOI 451. The system is in a recently discovered collection of stars known as the Pisces-Eridanus stream.The collection of stars in the system is less than three percent of the age of the solar system we live in and stretches across one-third of the sky. The system's planets were discovered in TESS images that are several years old, taken between October and December 2018. Follow-up studies of TOI 451 were conducted in 2019 and 2020 using the Spitzer Space Telescope and ground-based observatories.

Spitzer has been retired since conducting its studies. Scientists also used archival infrared data from the NASA NEOWISE spacecraft when it was known as WISE that was collected between 2009 and 2011. All of the data gathered on the planetary system suggests it has a cool disc of dust and rocky debris.

Data also suggests that TOI 451 likely has a pair of distant stellar companions that circle each other at a vast distance beyond the planets. Researchers are interested in the star system because it's only 120 million years old and only 400 light-years away. Its relatively close distance on a cosmic scale allows for detailed observations of the young planetary system.

The planets themselves are between two and four times Earth's size and are considered promising targets for testing theories on how planetary atmospheres are formed. NASA notes that stellar streams form when the gravity of the Milky Way galaxy tears apart star clusters or dwarf galaxies. In these cases, the individual stars move out along the cluster's original orbit and form an elongated group that gradually disperses.