The glowing tracery of highly active spiraling tendrils reveals invisible magnetic activity across the surface of the sun, in a newly released NASA video.
A combination of computer modeling and solar imagery was used to visualize the sun's magnetic structure, offering a peek at the intense and dramatic activity that keeps the star's engine running, according to the video shared online by NASA on Jan. 29.
Though invisible, the sun's magnetic field is a powerful force that not only drives the flow of solar material but extends to reach all the planets in the solar system. It affects our spacecraft and satellites, and generates the intense solar activity that can cause auroras and disrupt radio communication on Earth.
In the video, color-coding indicates different types of magnetic field lines. The green and purple filaments are open magnetic field lines, extending from the sun's core and reaching far out into space. They represent the sun's north and south polarity — like Earth, the sun has poles, magnetic regions at opposite ends of its "body." The white lines are closed magnetic field lines — unlike the open-ended polar lines, these lines loop back to rejoin the sun.
On the solar surface, plasma — matter made of gaslike charged particles heated to about 9,941 degrees Fahrenheit (5,778 degrees Kelvin) — is engaged in a never-ending, tireless ballet. The sun's magnetic field is both a participant and a choreographer in this intricate dance, made visible in the plasma's loops while also generating the energy that propels them.
Plasma's roiling movements on the solar surface are fluid and graceful, with glowing arches that emerge and collapse, and strands that extend and retract. But the sun's surface also frequently erupts in sudden and violent explosions known as coronal mass ejections, when giant clouds of plasma are blown off the sun and out into space. Interacting magnetic field lines can generate these explosive events, and models like this one help scientists predict when disruptive coronal mass ejections and solar flares are likely to happen.
While models help scientists visualize and track the sun's magnetic field, its origins are still uncertain. "It could be close to the solar surface or deep inside the sun — or over a wide range of depths," Dean Pesnell, a space scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland, said ina statement.
The cycle of energy exchange in the plasma's dance is certainly beautiful to watch, but it also generates important information about how magnetism behaves in stars, and how that can affect nearby planets. Modeling the mechanisms that propel solar activity and keep the sun's engine running offers a glimpse not only into the secrets of the closest star to Earth, but into the processes of other stars — in our galaxy and beyond.