The Sun is a mature star that has existed for more than 4.6 billion years. NASA estimates that it has about five billion years left before it dies out. These kinds of stars are known to be secure and stable, while young stars, on the contrary, could be quite unpredictable and brash.
Such a case is apparent with the star, V1298 Tau. A group of scientists has recently found out that the star was causing four of its young exoplanets to "shrink" due to its continuous "roasting" on the baby planets. Scientists believe that eventually, the tiny celestial bodies would be reduced into nothing but a core.
In the study, the authors wanted to figure out how much young stars disturb other planets' atmosphere over some time. Furthermore, when searching for habitability among exoplanets, scientists usually check on the atmosphere first as it needs to be thick enough for the transference of heat and providence of insulation.
The study's findings suggest that two of the innermost planets could wind up completely losing their gas atmospheres, leaving behind a rocky core. On the other hand, they also convey that the outermost planets, being a bit further from the host star, could end up being massive gaseous planets, like Jupiter.
The authors believe that their findings would aid in the current quest to find habitability on heavenly bodies outside our Solar System. Moreover, they believe it narrows down key characteristics that experts search for in their host stars. The findings of the latest discovery were published on the Monthly Notices of the Royal Astronomical Society on May 30, 2020.
The Host Star V1298 Tau
V1298 Tau is a star that is approximately just about the size of the Sun, but only has around 25 million years under its fiery hot belt. It is situated about 350 light years away from the Earth and is estimated to be 1.3 times bigger than our Sun.
It is considered a member of the Taurus-Auriga association in the Taurus Molecular Cloud. Alternately, it is also part of a projected moving group, called Group 29 that is somewhat a bit older.
The problem with young stars is that they tend to produce X-ray radiation that's around one thousand to ten thousand times more than the Sun. Experts say that it has to do with a star's rotation over time. As a star ages, their rotation slows down, which reduces the strength of their magnetism and X-ray emissions.
Young Exoplanets Left to Roast
The four tiny planets orbiting around V1298 Tau were discovered using the Kepler space telescope in the K2 mission. One of them was found in August 2019, while the other three were discovered later in November of the same year.
Experts say that the two innermost planets that circulate closer to the star are about the same size as Neptune, while the outermost planets are around the same size as Saturn.
According to the lead author of the study, Katja Poppenhäger, they analyzed the X-ray spectrum of the star using the Chandra space telescope. Furthermore, the astrophysics professor at the University of Potsdam, Germany, said that it allowed them to have an idea of how strongly the planetary atmospheres are illuminated.
Moreover, scientists observed the ghastly specifics of V1298 Tau's effect on its four baby planets. The researchers found that the planets are continuously being "roasted" by the radiation emitted by their star. In conclusion, their infantile bodies were being zapped by the gaseous envelope enclosing them until they shrink into nothing.