Violent superfluous endanger the planets surrounding young red dwarfs

Red dwarfs are small, slow-burning stars that can live Billions years before they run out of fuel. And thanks to their generous lifespan, the planets around them (at least those that are close enough to stay warm) are often considered as privileged places for the development of life. However, new research planned for publication in The astrophysical journal found that red dwarves tended to be rather abusive hosts, at least when they were young.

According to the study, young red dwarfs emit some of the most formidable redheads ever seen, often with 100 to 1,000 times more energy than their older counterparts. In fact, the bright eruptions of these tiny tiny stars are so powerful that they (pardon the pun) reduce on average the solar flares of our own Sun, much bigger – and that's a problem for any fledgling life that is trying to root around the red dwarf babies.

With the help of the Hubble Space Telescope, the authors of the new study are currently conducting a study called HAbitable Zones and Dwarf Activity Through Time, or HAZMAT. "The goal of the HAZMAT program is to help understand the livability of planets around low-mass stars," said Evgenya Shkolnik, senior researcher of HAZMAT, in a press release. "These low-mass stars are of paramount importance for the understanding of planetary atmospheres."

Three stars out of four of the Milky Way (and probably the entire cosmos) are red dwarfs, commonly called M dwarves. As these stars are so abundant, astronomers believe that most "habitable" exoplanets – planets that can withstand liquid water on their surface – are probably red dwarf stars in orbit.

However, housing liquid water is not the only condition of life as we know it. We must also consider incoming radiation from torches that, if powerful enough, can wreak havoc on the surface of the planet. This is especially true for planets around red dwarfs, which must sit very close to their host stars in order to receive enough heat to be considered habitable.

To study the global activity of stray light from these stars, the HAZMAT project uses far ultraviolet radiation to probe red dwarfs belonging to three age groups: young, intermediate and old. Although it has been known for a long time that red dwarfs, during their first few hundred million years, are powerful emitters of ultraviolet light, the exact processes causing the amplified ultraviolet signals are not yet well understood. If a significant percentage of the ultraviolet light from young red dwarfs turns out to be due to loud splinters – which occurs when magnetic field lines mingle and eventually break within a star – then l & rsquo; Atmosphere of all the planets surrounding red dwarfs may be in danger of being stripped. It would mean a disaster for extraterrestrial life that tries to survive on the surface of the nascent planet.

With the help of Hubble, the researchers monitored the surfaces of 12 red dwarfs located between 120 and 165 light-years from Earth. In less than a day of observation time, the team detected 18 bright bursts of young stars, some 40 million years old. The researchers detected 10 of 18 flares with an energy of more than 10²³ Joules, which is about the amount of energy that hits the surface of the Earth from the Sun in a week. The most powerful rocket they observed, nicknamed "Hazflare", was published about 10 times earlier.²⁵ joules of energy, putting him on par with the most energetic solar torch ever recorded.

"With the Sun, we have a hundred years of good observations," said lead author, Parke Loyd, of Arizona State University. "And at that moment, we saw one, maybe two, flares that have an energy approaching that of the Hazflare. After a little less than a day of Hubble's observations of these young stars, we caught the Hazflare, which means that we observe super-surfaces occurring daily or even several times a day. "

Although new discoveries indicate that planets around Young Red dwarfs are not very well suited to the development of life, the HAZMAT team hastens to find that the existence of life around these stars is not ruled out.

"Flares, like those observed, have the ability to strip the atmosphere of a planet. But that does not necessarily mean that life on the planet is dark and gloomy, "Loyd said. "Life could be different than we imagine. Or, other processes could restore the atmosphere of the planet. It is a difficult environment, but I would hesitate to say that it is a sterile environment. "

In addition, although eruptions of young red dwarfs are powerful enough to prevent the formation of early life, older red dwarfs may not have the same problem. So far, the team has examined red dwarfs only during their terrible two dead ends, but it remains to be seen how the more mature red dwarves act as they age. To do this, the next phase of the HAZMAT study will examine the activity of the middle aged red dwarf flares – those around 650 million years old – before moving on to the older age group.

So stay tuned, as continuing to study the evolution of the red dwarf (and, hopefully, to shut up), we will better understand the true livability of planets orbiting the type of dwarf. most prevalent star in the universe.