DISCOVERIES
Survivor
Scientists recently discovered a far-away planet that appears to have survived being engulfed by the rapid expansion of its dying star, Cosmos Magazine reported.
Some 520 light-years from Earth, astronomers found that the Baekdu star in the Ursa Minor constellation was burning helium rather than hydrogen.
They explained that as the star was approaching its end-of-life cycle it was expanding into a red giant that could threaten nearby planets orbiting it.
However, researchers wrote in their study that the Jupiter-like gas giant planet known as “Halla” did not get engulfed by the red giant, despite closely orbiting its host star.
“As it exhausted its core hydrogen fuel, the star would have inflated up to 1.5 times the planet’s current orbital distance – engulfing (Halla) completely in the process – before shrinking to its current size,” said co-author Daniel Huber.
Huber and his colleagues had conducted observations in 2021 and 2022, suggesting that Baekdu would at one point have been larger than Halla’s orbit. But the data confirmed the planet’s 93-day orbit has been stable for more than 10 years.
Now the question that Huber and others are asking is how did Halla survive this cataclysmic event.
Among their theories, they suggested that the Baekdu system was originally made up of two stars that “fed” off each other during the transition. This scenario prevented one of the celestial bodies “from expanding sufficiently to engulf the planet.”
Another possibility is that Halla is a new planet created when the two stars collided.
Whichever the case, it’s not certain if Earth will have the same luck when our sun becomes a red giant in five billion years.
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