Scientists shocked by 1.5 million year age gap between two stars

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Scientists imagine they’ve discovered the reason for a stunning age gap between two very unusual stars.

The pair, situated 1000’s of sunshine years away, has a 1.5 million year outdated distinction between their two ages.

Pairs of stars are normally a lot the identical age, being born like twins, researchers mentioned. But within the HD 148937 star system, the extra large star is at the least 1.5 million years youthful.

There are but extra mysteries concerning the system: it’s surrounded by a nebula that’s a lot youthful than each, and is fabricated from parts that normally are discovered contained in the star itself.

Researchers imagine that one other third star completely modified the destiny of the system, and is answerable for the weird nature of the pair.

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, making a “beautiful” cloud of fuel and mud, or nebula, surrounding HD 148937.

This merger seemingly occurred round 2.6 million years in the past, the place the newly fashioned star additionally grew to become magnetic, in contrast to its older counterpart.

The researchers mentioned their findings, revealed within the journal Science, helps resolve two long-standing mysteries: why two stars on this binary star system have an enormous age distinction, and the way large stars – with a mass that’s eight or extra 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 crew of worldwide scientists analysed 9 years’ price of knowledge from HD 148937, which is round 3,800 gentle years away from Earth, situated within the course of the Norma constellation.

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

While magnetic fields are frequent in low-mass stars just like the Sun, extra large stars can’t maintain magnetic fields in the identical manner.

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 occurring.

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.”

Additional reporting by Press Association