Much like our Sun, these flares would track around magnetic field lines that work like cosmic particle accelerators, bending the path of electrons and making them emit telltale radio signals that can be recognized with ALMA.
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The red dwarf in question, codenamed TVLM 513-46546, is especially interesting, according to the study published this week in The Astrophysical Journal.
An artist’s impression of the red dwarf TVLM 513-46546, which sports an intense magnetic field (indicated by the blue field lines) that triggers powerful solar flares. This fits with observations indicating that young stars, particularly red dwarfs, can be much more active than their older brethren. However, astronomers have now identified a tiny star with a monstrous temper. “In fact, it might be extremely hard for life to evolve at all in such a stormy environment”, Peter Williams of the Harvard-Smithsonian Center for Astrophysics (CfA), said in a release.
Take TVLM 513-46546 for example. One thing that makes this small star exceptional is that it spins quickly, finishing a full rotation around every two hours. It is so cool and small that it can be considered between brown dwarfs and stars, they added.
“If we lived around a star like this one, we wouldn’t have any satellite communications”.
‘In fact, it might be extremely hard for life to evolve at all in such a stormy environment’. Compare that with our sun, which takes almost a month to spin once on its axis. The red dwarf also boasts a magnetic field several hundred times stronger than our sun’s, which may explain the violent storms.
“This star is a very different beast from our Sun, magnetically speaking”, states CfA astronomer and co-author Edo Berger.
For their study, they used the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile and determined the star produced emissions 10,000 times brighter as well.
When studying the object with ALMA, the researchers detected powerful radio signals that betrayed the star’s magnetic personality. Although our sun can muster the strength to occasionally generate synchrotron emissions at these frequencies, only the most powerful solar flares can generate them.
When observing the star, the scientists caught sight of a “flare-like emission” from the red dwarf.
Having a mass of about 10 percent of that of the Sun, the star straddles the line between a star, which fuses hydrogen, and a brown dwarf, which does not.
This new information has important implications in the search for planets similar to our own outside of the Solar System. That proximity would put the planet right in the bull’s-eye for radiation that could strip its atmosphere or destroy any complex molecules on its surface, the astronomers speculate. “The dynamo operating in TVLM 513 seems to generate strong fields in a much more spatially uniform manner”.
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Next, astronomers will study similar stars to learn whether this star represents an entire class of tempestuous stars or is a freak of nature, confirmed the release.
