"A Planet Triumph Death" by Edward Yoon

Apocalyptic fate is being wrought by fading stars swallowing their planets in the vastness of the Milky Way. Unexpectedly, the planet Halla has defied this awful fate, suggesting that our galaxy may contain a hidden population of robust planets. A recent study that appeared in the journal offers a novel theory for Halla's persistence and hypothesizes an unusual past for its host star.

One of the study's authors, NASA Hubble Fellow Marc Hon, calls Halla a "forbidden planet,"

miraculously escaping destruction because of the peculiar past of its star.

Red giants, which grow in size and eat any neighboring planets, develop as stars near the

conclusion of their lives. Throughout the galaxy, indirect signs of these planetary engulfments have been seen, and just recently, astronomers made the first firsthand observation of a planet being eaten by its star. In other systems, planets even consume one another; one gas giant was discovered to have scavenged a world the size of Mercury.

The story of planetary engulfment has been given a fresh twist by Halla, which resembles

Jupiter. Only after studies with NASA's Transiting Exoplanet Survey Satellite were conducted a few years after its discovery in 2015 did its hazardous status become apparent. Through these studies, it was discovered that Halla's host star, Baekdu, had run out of hydrogen fuel and was currently consuming helium.

Red giants typically have greatly increased in size by the time they are in the stage of burning helium. Therefore, Halla, in a close 93-day orbit around Baekdu, should have already perished.

But further observations made by Dr. Hon and his associates in Hawaii using ground telescopes defied predictions and showed that Halla was still intact.

The research team put out an intriguing theory after ruling out all other explanations: Baekdu, also known as 8 Ursae Minoris, might have formed as the result of a star merger in the past. It's possible that this merger stopped either star from becoming massive enough to eat the nearby planets. Alternately, Halla might be a freshly formed "second-generation" planet that emerged from the star merger's intense afterglow.

No matter what happens, Halla's protection is only momentary. Baekdu, which is around 1.6

times as huge as the sun, is anticipated to go through another expansion soon. Dr. Hon asserts that while Halla did manage to escape death once, the likelihood of it surviving as its host star resumes its expansion increases.

The team's merger theory might also explain Baekdu's extremely high lithium concentrations, an element that isn't often seen in red giants but might be created during the fusion of two stars. The findings was praised by Andrew Vanderburg, an assistant professor of physics at M.I.T. who specializes in exoplanet research, who said that the team's conclusion is the most logical explanation he has come across. An expert on planetary engulfment at the University of Wisconsin-Madison named Melinda Soares-Furtado described it as a "exciting" illustration of unexpected traits resulting from interactions between stars and planets. She proposed that future studies of the system consult experts in blue stragglers, bright stars created during stellar mergers.

While looking for parallel worlds, Dr. Hon and his colleagues want to delve further into the

fascinating history of this strange system. The finding of planets like Halla continues to confound our assumptions, demonstrating an amazing resistance to the forces that would ordinarily spell their doom.