“The Big Mystery”: A rare planet that “remained” even at a very close distance from the Sun arouses the curiosity of astronomers | Sciences

This week, scientists announced the discovery of A A rare exoplanet Which defies astronomers' expectations, A discovery that could have implications for studying the future of our solar system.

It resembles the planet Neptune, which is six times larger than Earth.Planet Phoenix“,” as it was called, should have been reduced to just a rock with no atmosphere due to its proximity to its star Red gianta star at the end of his life.

But that didn't happen and TIC365102760 b, As it is technically called, it kept its atmosphere puffed with gases and other lighter materials.

“This planet is not evolving as we thought. Its atmosphere appears to be much larger and less dense than we would expect for these systems,” said Sam Grunblatt, an astrophysicist at Johns Hopkins University who led the study on the discovery. In a statement published in the “Astronomical Journal”.

“How it maintained this atmosphere despite being so close to this large host star is our big mystery,” the researcher added.

To discover this exoplanet, the researchers responsible for the study used a new method to adjust data received from the planet. Transit of the exoplanet survey satellite (he-goat(abbreviated in English) from NASA, the North American space agency.

Launched in 2018, this space telescope identifies low-density planets like Phoenix when their host stars dim as they pass in front of them.

In the study, scientists also combined data from this satellite with measurements from the satellite WM Keck Observatoryin Hawaii, which tracks signals emitted by stars caused by the planets orbiting them.

As a result, they discovered that Planet Phoenix is ​​smaller, older and hotter than expected. Moreover, he orbits his star every day 4.2 daysIt is six times closer to it than Mercury is to the sun.

“This is the smallest planet ever found orbiting a red giant star and is probably the least massive planet as well,” Gronblatt said.

However, TIC365102760 will not live more than 100 million years before it begins to die, as it is swallowed by its giant star.

According to scientists, given the “Phoenix”'s advanced age and scorching temperatures, in addition to its unexpectedly low density, the process of removing its atmosphere should take place soon. Slower pace Than he thought possible.

This should only happen in a few 5 billion yearsBut studying how stars of this type evolve in this way is a very important field of study in astronomy.

“We still have a long way to go in understanding how planetary atmospheres evolve over time,” Gronblatt said.

video: NASA robot discovers organic matter on Mars