A stunning nebula seems to carry a shock at its heart: a pair of stars that don’t match as they need to. Researchers wanting on the lovely NGC 6164/6165 nebula had been stunned to study that one of many pair of stars it hosts seems to be a lot older than the opposite, giving clues to the dramatic state of affairs during which the nebula was born.
Pairs of stars aren’t uncommon in nebulae, however they’re sometimes very comparable. Usually, you’d anticipate a pair to be comparable when it comes to age and mass, as they’d have shaped across the identical time. However on this nebula, situated 3,800 light-years away, one member of the pair is 1.5 million years older than the opposite, and the youthful star can be magnetic, not like its older counterpart.
This picture, taken with the VLT Survey Telescope hosted on the European Southern Observatory’s Paranal Observatory, reveals the attractive nebula NGC 6164/6165, often known as the Dragon’s Egg. The nebula is a cloud of gasoline and dirt surrounding a pair of stars known as HD 148937. ESO/VPHAS+ workforce. Acknowledgement: CASU
“When doing background studying, I used to be struck by how particular this method appeared,” stated the lead writer of the brand new analysis, Abigail Frost of the European Southern Observatory in Chile, in a press release. “A nebula surrounding two large stars is a rarity, and it actually made us really feel like one thing cool needed to have occurred on this system. When wanting on the knowledge, the coolness solely elevated. After an in depth evaluation, we may decide that the extra large star seems a lot youthful than its companion, which doesn’t make any sense since they need to have shaped on the identical time!”
The researchers obtained clues to the thriller from the character of the nebula itself, because it seems to be very younger in comparison with the celebs, at simply 7,500 years outdated. Additionally it is excessive in parts like nitrogen, carbon, and oxygen. In complete, the proof means that one thing dramatic occurred to kick off the existence of the nebula.
“We expect this method had no less than three stars initially; two of them needed to be shut collectively at one level within the orbit while one other star was way more distant,” defined one other of the researchers, Hugues Sana of KU Leuven in Belgium. “The 2 internal stars merged in a violent method, making a magnetic star and throwing out some materials, which created the nebula. The extra distant star shaped a brand new orbit with the newly merged, now-magnetic star, creating the binary we see right now on the heart of the nebula.”
This situation may also assist astronomers study how some large stars purchase magnetic fields, which may occur after a merger. Huge stars don’t keep magnetic for very lengthy in comparison with their lengthy lifetimes, so that is the primary time researchers have seen proof of this magnetism following a merger.
The analysis is printed within the journal Science.
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