UCLA: The Sun's Core Rotates Four Times Faster Than Its Surface
Posted: Wed Aug 02, 2017 4:55 pm
The Sun's Core Rotates Four Times Faster Than Its Surface
University of California, Los Angeles | 2017 Aug 01
Asymptotic g modes: Evidence for a rapid rotation of the solar core - E. Fossat et al
University of California, Los Angeles | 2017 Aug 01
Surprising observation might reveal what the sun was like when it formed
[img3="The sun, whose hot, dense core produces nuclear fusion and rotates nearly four times faster than its surface. Credit: Newton Science Magazine"]http://cms.ipressroom.com.s3.amazonaws. ... ba-prv.jpg[/img3][hr][/hr]The sun’s core rotates nearly four times faster than the sun’s surface, according to new findings by an international team of astronomers. Scientists had assumed the core was rotating like a merry-go-round at about the same speed as the surface. ...
The rotation of the solar core may give a clue to how the sun formed. After the sun formed, the solar wind likely slowed the rotation of the outer part of the sun, he said. The rotation might also impact sunspots, which also rotate, Ulrich said. Sunspots can be enormous; a single sunspot can even be larger than the Earth.
The researchers studied surface acoustic waves in the sun’s atmosphere, some of which penetrate to the sun’s core, where they interact with gravity waves that have a sloshing motion similar to how water would move in a half-filled tanker truck driving on a curvy mountain road. From those observations, they detected the sloshing motions of the solar core. By carefully measuring the acoustic waves, the researchers precisely determined the time it takes an acoustic wave to travel from the surface to the center of the sun and back again. That travel time turns out to be influenced a slight amount by the sloshing motion of the gravity waves ...
Asymptotic g modes: Evidence for a rapid rotation of the solar core - E. Fossat et al
- Astronomy & Astrophysics 604:A40 (Aug 2017) DOI: 10.1051/0004-6361/201730460
arXiv.org > astro-ph > arXiv:1708.00259 > 01 Aug 2017