It has been baptized as Kappa 1 Ceti and has a mass, radius, temperature and brightness similar to the Sun. The star is about 30 light years distant from Earth , as explained by the team at NASA’s Goddard Space Flight Center in Greenbelt, Maryland (USA).
This twin of the Sun would be between 600 and 750 million years old , which would represent a younger version of our Sun, since our star is considered middle-aged, at 4.6 billion years old.
Trace the past of the Sun
Finding a similar star but “a few years” less could help us understand conditions in the early solar system and how life formed on Earth. And, fortunately, the Milky Way has more than 100,000 million stars , of which one in ten shares characteristics with our Sun, a characteristic that we can take advantage of to analyze the early stages of development of stars similar to our own.
“Imagine that I want to reproduce a photo of an adult baby when he was one or two years old, and all his photos were erased or lost. Now he would look at a photo of them and the photos of their close relatives of that age and, from from there, I would reconstruct the photos of their babies, “said Vladimir Airapetian, senior astrophysicist in the Heliophysics Division at NASA’s Goddard Space Flight Center in Greenbelt. Maryland and first author of the new study . “That’s the kind of process we’re following here: looking at the characteristics of a young star similar to our own , to better understand what our own star looked like in its youth and what allowed it to foster life on one of its nearby planets.”
The sun is in the middle of its life
Scientists believe that the Sun could have rotated three times faster in its younger years compared to today . Most likely it had a stronger magnetic field and emitted more intense radiation. If the Earth already existed at that time, the impact of solar particles could be experienced around the world and not just at its poles.
This star, Kappa 1 Ceti, is also about the same age as our Sun when life developed on Earth.
To locate it, NASA astronomers relied on data collected from several disparate space missions, such as NASA’s Transiting Exoplanet Exploration Satellite, NASA / ESA Hubble Space Telescope, ESA’s XMM-Newton, and the NICER missions.
Multiple space agencies have sent instruments into space capable of measuring the sun’s stellar winds, but it is not yet possible to directly observe the stellar winds of other stars in our galaxy, such as Kappa 1 Ceti, because they are too far away. Studying the stellar winds is relevant because it can have a significant impact on the planets at any stage of life. We know that younger stars tend to generate hotter and more vigorous stellar winds and more powerful plasma eruptions than older stars.
Thus, understanding what the Sun was like when Earth was developing will help refine the search for stars with exoplanets that could host life in the future.
Referencia: Vladimir S. Airapetian et al, One Year in the Life of Young Suns: Data-constrained Corona-wind Model of κ 1 Ceti, The Astrophysical Journal (2021). DOI: 10.3847/1538-4357/ac081e
