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  • Ladies and gentleman, a star is born! Or rather, two stars.

  • This transfixing image features two circumstellar disks in which baby stars are growing,

  • taking in material from their surrounding disk.

  • This is the first time ever that weve witnessed the complex birth of binary stars in such vivid detail.

  • Stars are one of the most fundamental building blocks of space,

  • but the specific conditions under which they assemble remain elusive.

  • Which is why scientists are hoping that these new observations

  • will shine a light on their mysterious origins.

  • So, here’s what we do know about how stars form.

  • And no, it doesn’t involve finding an amazing agent

  • or scoring a spot on a hit TV show after years of dead-end auditions.

  • A star’s life begins inside a densely packed cloud of interstellar gas and dust.

  • These clouds are made up of various elementsmostly helium and hydrogenand are extremely cold.

  • This causes their resident atoms to huddle together in clumps,

  • which buckle under their own weight once they reach a certain density.

  • This collapse leads to fragmented clumps of matter, which now, broken free from the cloud core,

  • are able to take shape into a star.

  • Young stars are very impressionable and experience pressure coming at them from all different directions.

  • Gravitational pressure gets the star’s core hot enough for fusion reactions to begin,

  • while the star’s hot, unpredictable interior results in a huge outflow of energy

  • that helps to keep it from imploding.

  • When the forces that push and pull on the star are in balance, it becomes a stable adult.

  • Very relatable.

  • While stars mostly form in the same way, they take on all different kinds of identities,

  • from white dwarfs

  • to blue giants.

  • Most stars are classified by their luminosities and colors,

  • which can shift throughout their life as they grow and age

  • Stars are also defined by their social status.

  • Our star, the Sun, is the sole provider of Earth’s light and entertainment,

  • but most stars roll with a crew, belonging to systems where two or more stars

  • are gravitationally bound to one another.

  • While there’s some debate as to why this is,

  • a recent statistical model suggests that all stars initially form as binaries,

  • then drift apart over a million years.

  • Even our dear Sun is thought to have a long-lost twin out there somewhere in the galaxy.

  • Developing equipment powerful enough to capture detailed views of distant stars also remains a challenge.

  • Stars typically evolve over millennia,

  • so observing them in real time isn’t very compatible with our relatively short lives.

  • What we know about star formation has been pieced together using data from instruments

  • like radio telescopes, gamma-ray telescopes,

  • and space-based telescopes like Hubble.

  • But our knowledge of the early lives of stars remains limited,

  • which is why this new observation is so exciting.

  • Located roughly 700 light-years away in the Ophiuchus constellation,

  • within a pipe shaped dust lane called the Pipe Nebula,

  • lies the binary [BHB2007] 11.

  • Astronomers had already seen a rough outline of the two protostars and their surrounding structures,

  • but this image offers an unprecedented look

  • into the detailed network of gas and dust filaments circling them.

  • By leveraging the seeing power of the ALMA radio telescope,

  • an international team of researchers were able to observe two circumstellar disks in the binary system,

  • and a massive surrounding disk totaling about 80 Jupiter masses.

  • Most strikingly, the new data revealed that the developing stars shed their mass from the bigger disk,

  • or the circumbinary disk, in a two-level process.

  • The first part happens when mass is transferred from the shared disk

  • to the individual circumstellar disks in swirling loops,

  • which is what these new images show.

  • Researchers also found that the smaller but brighter circumstellar disk

  • the one in the lower part of the imageaccretes more material.

  • In the second stage, the two stars accrete mass as a single unit.

  • Since these feeding filaments connect the stars to their birth disk,

  • this new knowledge provides important constraints for existing models of how stars form.

  • While this two-level accretion process is suspected to be the driver of binary systems,

  • the researchers admit that more data will be needed to build a more stable star formation model.

  • But if this breakthrough is any indication,

  • the future of high-tech stargazing is very bright!

  • Are there other stellar discoveries that you’d like to see us cover?

  • Let us know down in the comments below.

  • Don’t forget to subscribe to Seeker, and thanks for watching!

Ladies and gentleman, a star is born! Or rather, two stars.

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B2 中高級

科學家剛剛見證了兩顆恆星誕生的驚人細節。 (Scientists Just Witnessed the Birth of Two Stars in Stunning Detail)

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    林宜悉 發佈於 2021 年 01 月 14 日
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