By Sonia Fernandez, UCSB
Researchers at UC Santa Barbara, The University of Texas at Austin, Yale University and National Taiwan Normal University have found that a fair number of sun-like stars emerge with their rotational axis tilted with respect to their protoplanetary disks, the clouds of gas and dust from which solar systems are born.
“All young stars have these disks, but we’ve known little about their orientations with respect to the spin axis of the host stars,” said UCSB associate physics professor Brendan Bowler, who studies how planets form and evolve through their orbits and atmospheres, and is senior author of a study in the journal Nature. Based on the general alignment of our own sun’s rotational axis with those of the planets in our solar system, the assumption was that stars and their planet-forming disks emerge and rotate in or very close to alignment, he explained.
“This work challenges these centuries-old assumptions,” Bowler said.
Ever since exoplanets — planets that orbit other stars — were discovered in the early 1990s, the variety of spin orientations of host stars relative to the orbits of the planets closest to them had astrophysicists scratching their heads.
“It came as quite a surprise that some planets were on orbits that were extremely inclined relative to the spin axis of the host star,” said Lauren Biddle, a postdoctoral researcher at UT Austin, and lead author of the study. Since then, there have been efforts to explain the dynamics that could lead to this planetary system architecture.
To find out, the researchers took data from the Atacama Large Millimeter/submillimeter Array (ALMA), the Transiting Exoplanet Survey Satellite (TESS) and the repurposed exoplanet-seeking Kepler Mission (K2) to measure stellar and disk inclinations and obtain star-disk obliquity for a sample of 49 young isolated stars and their planet-forming disks.
The result of their survey? About two-thirds of the stars and protoplanetary disks were found to be in alignment, while a third of them were misaligned. The modest number of misaligned stellar and planet-forming disk orientations hints at a more elegant model of the origin of planetary system tilts: some are just born that way.
“It changes our interpretation,” he continued. “It means that we don’t need a ton of post-formation dynamics and interactions and planet-scattering events.” Certainly, there are suns and planetary systems that do undergo significant interactions, and can only be explained by complex dynamics, according to Bowler. And, he added, studying other stars and their solar systems gives context to our own six-degree misalignment between our own sun and solar system.
“If we think of science as kind of an Occam’s razor where the least complex model ends up winning out, given the data, this is a nice example of the sun simply just fitting into this primordial, stellar obliquity distribution,” Bowler said.
Future work in this realm may include further investigations into just how these sun-like stars and their protoplanetary disks create these tilted orientations during the earliest stages of solar system formation.
“Now we know that at least a third of them are tilted,” said Bowler, but why this is the case remains unanswered.
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Yeah….ooohhh. If you’re relying on federal funding for this kind of stuff as a scientist you might be looking to start collecting coupons, not making any big purchases, no vacations, etc. for a while. Not saying there’s no value, but dang – so esoteric and you should be smart enough to realize you are on the chopping block about now.
Some idiots have no clue how much basic research ends up benefitting us all in the long run.
Good thing X-rays weren’t dismissed as esoteric nonsense.
I would rather cut funding for drones that sit at desks dispensing hypocritical advice, feeling contempt for their employers and clients all the while collecting a salary from taxpayers.
So scientists should fund themselves, he BASICNOEDUCATION?
I would say that is good information for everyone right now, 805. I hope you, along with everyone else, is planning for another great Republican Depression. And when that Orange Smudge on History gets a toadie in there to artificially reduce the Fed rate then it’s all over. Hope you’re a billionaire with plenty of cash on hand. Buckle-up BasicFoxNewsZombie and everyone else. If you’re not scared out of your mind then you’re not paying attention.
You and I should just agree that we hope the Democrats can right their ship back to something that actually makes common sense. I’ll vote for a Clinton type tomorrow over Trump. I don’t think you get it.
But we all know you don’t get it. You provide multiple examples every day.