Wandering Star Disrupts Star Nursery: Event Provides New Evidence That Traveling Stars Can Form Binary Systems

From a distant zoomed-out view, star-forming cloud L483 appears normal. But as a team of astrophysicists led by Northwestern University zoomed in closer and closer, things got weirder and weirder.

When the researchers looked closer into the cloud, they noticed that the magnetic field had been strangely twisted. And then — while they were examining a newborn star in the cloud — they saw a hidden star hidden behind it.

“It’s basically the star’s sibling,” said Erin Cox of Northwestern, who led the new study. “We think these stars formed far apart and one moved closer to another to form a binary star. As the star got closer to its sibling, it shifted the cloud’s dynamics around its magnetic field. to twist.”

The new findings provide insight into binary star formation and how magnetic fields affect the earliest stages of developing stars.

Cox will present this research at the 240th meeting of the American Astronomical Society (AAS) in Pasadena, California. “The Twisted Magnetic Field of L483” will take place on Tuesday, June 14 as part of a session on “Magnetic Fields and Galaxies”. The Astrophysical Journal will also publish the study next week.

Cox is a postdoctoral fellow at Northwestern’s Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA).

twisted mystery

Stellar nurseries are wild and wonderful places. As dense clouds of gas and dust collapse to form stars, they launch outflows of stellar material at hypersonic speeds. A magnetic field around a star-forming cloud is typically parallel to these outflows. When Cox and her collaborators observed the large-scale L483 cloud, they found just that. The magnetic field matched this typical profile.

But then the astrophysicists decided to take a closer look at NASA’s Stratospheric Observatory for Infrared Astronomy (SOFIA), and then things got weird. In fact, the magnetic field was not parallel to the outflow of the newborn stars. Instead, the field was rotated at an angle of 45 degrees to the outflow.

“In the beginning, it matched what the theory predicts,” Cox said. “If you have a magnetized collapse, the magnetic field determines how the star forms. We expect to see this parallelism. But theory can say one thing, and observations can say another.”

Unusual binary formation

Though more sightings are needed, Cox believes a previously hidden sibling may be responsible for the warped field. Using SOFIA, the astrophysics team discovered a newborn star forming in a shell of material. But upon closer examination with radio telescopes from the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, the researchers spotted the second star, sharing the same stellar envelope.

“These stars are still young and still forming,” Cox said. “The stellar envelope provides the material to form the stars. It’s like rolling a snowball in the snow to make it bigger and bigger. The young stars ‘roll’ in material to build mass.”

About the same distance as our sun from Pluto, the two young stars form a binary star system. Currently, astrophysicists agree that binary stars can form when star-forming clouds are large enough to produce two stars or when the disk orbiting a young star partially collapses to form a second star.

But for the twin stars in L483, Cox suspects something unusual is going on.

“There is newer work suggesting that it is possible to have two stars form far from each other, and then one star gets closer to form a binary,” Cox said. “We think this is happening here. We don’t know why one star would move to another, but we think the moving star shifted the dynamics of the system to twist the magnetic field.”

Cox believes this new work may eventually provide new insights into how binary stars — and the planets that orbit around them — form. Most people are familiar with the iconic scene from ‘Star Wars’, in which Luke Skywalker looks wistfully up at the double stars around which his home planet Tatooine orbits. Now scientists know that this scenario isn’t just science fiction; planets orbiting binary stars could potentially be habitable worlds.

“Learning how binary stars form is exciting because planet and star formation occur simultaneously and binary stars interact dynamically,” Cox said. “In our census of exoplanets, we know planets exist around these binary stars, but we don’t know much about how these planets differ from the planets that live around isolated stars. With new tools coming online to discover and interact with new binary stars.” we will be able to test these results with a statistical sample.”

The study, “The twisted magnetic field of the protobinary L483,” was supported by NASA and the National Science Foundation.

#Wandering #Star #Disrupts #Star #Nursery #Event #Evidence #Traveling #Stars #Form #Binary #Systems

Leave a Comment

Your email address will not be published. Required fields are marked *