Scientists solve mystery of why star pair has more than a million-year age gap

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Scientists imagine they’ve solved the mystery of why a unusual pair of stars 1000’s of gentle years away has more than a million-year age gap.

Star pairs are normally very related in age, like twins, the researchers mentioned – however in case of the HD 148937 star system, one is round 1.4 million years older then the opposite.

The staff believes HD 148937 had a violent previous involving a third star that endlessly altered its destiny.

Analysing knowledge from the European Southern Observatory (ESO), it believes there have been initially three stars within the system however two of them clashed and merged, creating a “beautiful” cloud of gasoline and dirt, or nebula, surrounding HD 148937.

This merger doubtless occurred round 2.6 million years in the past, the place the newly fashioned star additionally grew to become magnetic, not like its older counterpart.

The researchers mentioned their findings, revealed within the journal Science, helps solve two long-standing mysteries: why two stars on this binary star system have a enormous age distinction, and the way large stars – with a mass that’s eight or more instances that of the Sun – get their magnetic fields.

Hugues Sana, a professor at KU Leuven in Belgium and the principal investigator of the observations, mentioned: “We think this system had at least three stars originally; two of them had to be close together at one point in the orbit whilst another star was much more distant.

“The two inner stars merged in a violent manner, creating a magnetic star and throwing out some material, which created the nebula.

“The more distant star formed a new orbit with the newly merged, now-magnetic star, creating the binary we see today at the centre of the nebula.”

Dr Abigail Frost, an astronomer at ESO in Chile, added: “A nebula surrounding two massive stars is a rarity, and it really made us feel like something cool had to have happened in this system.

“When looking at the data, the coolness only increased.

“After a detailed analysis, we could determine that the more massive star appears much younger than its companion, which doesn’t make any sense since they should have formed at the same time.”

A staff of worldwide scientists analysed 9 years’ value of knowledge from HD 148937, which is round 3,800 gentle years away from Earth, positioned within the course of the Norma constellation.

The knowledge got here from ESO’s Very Large Telescope Interferometer (VLTI) and is positioned within the Atacama Desert in Chile.

While magnetic fields are widespread in low-mass stars just like the Sun, more large stars can not maintain magnetic fields in the identical means.

Yet roughly 7% of large stars have been noticed to have magnetic fields, scientists say.

While astronomers had suspected for a while that large stars might purchase magnetic fields when two stars merge, that is the primary time scientists have discovered direct proof of it taking place.

Dr Frost mentioned: “Magnetism in massive stars isn’t expected to last very long compared to the lifetime of the star, so it seems we have observed this rare event very soon after it happened.”