Astronomers have discovered planets that shouldn’t exist

In fact, the planet should have been stripped to rocks by the intense radiation from its nearby parent star. But instead, strangely, the planet developed a “thin” atmosphere.

Astronomers have discovered a very special planet orbiting a ferocious red giant star. It’s about a world being bombarded by the unforgiving radiation of its parent star. Normally, in such a situation, planets would be completely stripped of their atmosphere. But somehow this planet managed to avoid this fate.

Phoenix
The newly discovered planet has been officially named TIC365102760 b, but is known by the slightly catchy nickname “Phoenix.” The planet, which is 6.2 times larger than Earth, completes an orbit around its parent star every 4.2 days, and is about 6 times closer to its star than Mercury is to the sun. Because its parent star is also a red giant, Phoenix is ​​exposed to intense and continuous radiation. In most cases, planets orbiting such violent stars would be completely stripped away, but Phoenix gets away with this dance. Somehow he manages to maintain a ‘subtle’ atmosphere.

Thin planets are usually made of gases, ice, or other lighter materials, making them generally less dense than any planets in our solar system. They are so rare that scientists estimate that only about 1 percent of stars have them. Exoplanets like Phoenix are not discovered often because their smaller size makes observing them more difficult than observing larger, denser planets.

Researchers face a dilemma. Because actually Phoenix shouldn’t be able to exist at all. “The evolution of this planet is different than expected,” says study leader Sam Grunblatt. “The atmosphere appears to be much larger and less dense than we would normally expect for such a system. The big question is how this planet managed to maintain its atmosphere despite its proximity to its parent star.”

Hot Neptune
This new planet belongs to a rare class of worlds known as “hot Neptune”, due to its similarity to the frozen outer giant of our solar system. Unlike that distant giant, hot Neptune is much closer to its host star and much warmer. However, surprisingly, Phoenix is ​​smaller, older and hotter than scientists thought. “This is the smallest planet we have ever discovered around a red giant,” Gronblatt says. “It also likely has the lowest mass of any planet ever observed around a red giant star. That’s why it looks really strange. We don’t understand why it still has an atmosphere, while other ‘hot Neptunes’ are much smaller and much closer to their host star.” It actually loses its atmosphere in less extreme conditions.

Slow down
Researchers are still in the dark about why. They wrote in their article that Phoenix’s age and scorching temperatures, combined with its unexpectedly low density, mean that the process of dismantling its atmosphere should occur at a slower pace than scientists had thought. Their studies. They also suspect that the planet’s density is 60 times less dense than the less dense former hot Neptune. Phoenix is ​​not expected to have a very long life. The planet is unlikely to survive for more than 100 million years before heading toward its parent star and dying.

The discovery of Phoenix is ​​forcing scientists to rethink prevailing theories about how planets age and die in extreme environments. In addition, it highlights the enormous diversity of solar systems and the complexity of planetary evolution.

Soil
But not only that. The results also help scientists understand how atmospheres similar to Earth’s evolve over time. Within a few billion years, the Sun will also swell into a red giant star, engulfing Earth and the other inner planets. “Our understanding of the late evolution of planetary systems is still very limited,” says Gronblatt. “The results suggest that Earth’s atmosphere may not develop as we expect.”

In follow-up research, Grunblatt and his team plan to continue searching for more small worlds like Phoenix. And they’re in good shape with planet hunter Tess. This telescope can detect low-density planets because they obscure the brightness of their parent star as they pass in front of it. The researchers then use the W.M. Keck Observatory located at the Maunakea volcano in Hawaii to refine the data further. In this way, the researchers have already found dozens of potential candidates. Hopefully this will eventually provide further insight into the mysterious evolution of distant planets. Although we’re not there yet. “We still have a long way to go in understanding how planetary atmospheres evolve over time,” Grünblatt concludes.