New studies reveal that older stars have weaker magnetic braking, suggesting that they might be prime locations for finding alien life.
Once upon a cosmic time, scientists assumed that stars apply an eternal magnetic brake, causing an endless slowdown of their rotation. With new observations and sophisticated methods, they now peeked into a star’s magnetic secrets and found it wasn’t what they expected.
The cosmic hotspots for finding alien neighbors might be around stars hitting their midlife crisis and beyond. This groundbreaking study, shedding light on magnetic phenomena and habitable environments, has been published in the
Rethinking Magnetic Braking in Stars
Stars like the Sun are born spinning rapidly, which creates a strong magnetic field that can erupt violently, bombarding their planetary systems with charged particles and harmful radiation. Over billions of years, the rotation of the star gradually slows as its magnetic field drags through a wind flowing from its surface, a process known as magnetic braking. The slower rotation produces a weaker magnetic field, and both properties continue to decline together with each feeding off the other. Until recently, astronomers assumed that magnetic braking continues indefinitely, but new observations have started to challenge this assumption.
New Insights From Advanced Observations
“We are rewriting the textbooks on how rotation and magnetism in older stars like the Sun change beyond the middle of their lifetimes,” says team leader Travis Metcalfe, a senior research scientist at White Dwarf Research Corporation in Golden, Colorado, USA. “Our results have important consequences for stars with planetary systems, and their prospects for developing advanced civilizations.”
Klaus Strassmeier, director at the Leibniz-Institute for Astrophysics in Potsdam, Germany and co-author of the study, adds “This is because weakened magnetic braking also throttles the stellar wind and makes devastating eruptive events less likely.”
Evidence From NASA’s Kepler and TESS Missions
The team of astronomers from the United States and Europe combined observations of 51 Pegasi from DOI: 10.3847/2041-8213/ad0a95