Among stars, 49 Lib was considered to be of teen age. However, researchers are saying now that it is 12, not 2.3 billion years old, making it 10 billion years older than earlier believed.
Conflicting data about 49 Lib is to blame for this. For decades, researchers have estimated it was younger, but Rolf Chini and Klaus Fuhrmann resolved these inconsistencies, publishing the results of their work in the Astrophysical Journal.
"It had previously been assumed that the star was only half as old as our sun. However, our data have shown that it had formed at the time that our galaxy was born," explained Chini.
What caused the error? 49 Lib, it turns out, was a binary star system, which another study proved last year. Knowing this, Chini and Fuhrmann were able to demonstrate how the star's partner managed to fake its age.
Determining Star Age
49 Lib's partner was almost extinguished that the other star might as well have been invisible. At the end of its life, however, the partner star transferred a portion of its matter to 49 Lib.
Researchers rely on chemical compositions to figure out what a star's age is. To determine chemical composition, they turn to light emitted by a star, breaking it down to separate components. They'll then get to decoding the wavelength at which a star emits light the most. Researchers will refer to a star's spectra, which is determined by its chemical composition, for its age.
Older stars were formed early in the universe's birth so they don't contain heavy elements, which were only generated later on when numerous star generations underwent nuclear fusion. Younger stars like the sun have heavy elements because they were formed from the remnants of earlier star generations.
When 49 Lib's partner transferred its matter to the star, it also transferred heavy elements. As such, when these heavy elements were detected, it led researchers to think that 49 Lib was a young star.
49 Lib's Fate
Based on their research, Chini and Fuhrmann were also able to track the binary star's evolution, figuring out at which masses 49 Lib and its partner started out and how these masses have undergone evolution since then.
Initially, both 49 Lib and its partner had masses similar to the sun. However, when the star absorbed some of its partner's mass, it gained about 0.55 solar masses of weight. Given the more massive a star is, the shorter its life, the weight gain led to a dramatic reduction in 49 Lib's lifespan.
According to Chini, it won't be long before 49 Lib becomes a red giant and then collapses and becomes a white dwarf. When it turns into a red giant, 49 Lib will undergo the same process its partner did, unable to hold its matter together. Funnily, some of 49 Lib's matter will be attracted by its extinguishing partner. And if that partner is unable to rid itself of matter via small eruptions, it will meet its demise by exploding like a supernova.
