Montana And European Scientists Take Sun's Temperature; Results Published In This Week's Nature

June 11, 1998

BOZEMAN, MT--Scientists long perplexed over why the sun's corona is so hot now have a new clue about the actual heating mechanism that pushes temperatures in the sun's outer region into the millions of degrees.

Montana State University-Bozeman researcher Loren Acton, Eric Priest of St. Andrews University in Scotland and a team of European scientists have discovered that a clash of magnetic fields is likely to cause the heating of gigantic and super-hot loops of material that arch high above the sun's surface.

Their findings are reported in the June 11 issue of the journal Nature.

Published in England, Nature is an international weekly journal of science whose articles are intended for a broad scientific audience. For decades, scientists have known that the surface of the sun is about 6,000 degrees Celsius while the corona soars to several million degrees.

"The outer part of this atmosphere forms a giant halo of eerie light around the sun during a solar eclipse and consists of giant, super-hot loops that extend high above the sun's surface," Priest wrote in a press release from St. Andrews University.

Using the Soft X-ray Telescope aboard the Japanese/US/UK space satellite called Yohkoh, which means "sunbeam," the research team led by Priest has for the first time measured how the temperature varies along the giant loops.

Physicists had three interpretations of how the corona is heated. Some thought that heat is likely to be dumped at the feet of the loop and then conducted, like the flow of heat along a red-hot poker, to the rest of the loop. Others believed the heat should be deposited at the summit of the loop, while a third group predicted a uniform release of heat along loop, said Acton.

"Our data indicate that the heating must be uniform," he said.

The most likely mechanism is a clash of magnetic field lines, according to Priest.

"They tangle like spaghetti in the solar atmosphere and break, causing dozens of explosions that release energy along the loop," he wrote in the press release.

Acton said the finding "in no way" solves the puzzle of the corona's intense heat, but it does point the scientists toward the correct heating mechanism.

"It's a step in understanding the heating of the corona in general, but it's a far cry from reproducing in the computer what nature does," he said. Although it appears constant from the earth, the sun is a bubbling cauldron of energy now more visible to Acton and other scientists thanks to a variety of satellites that orbit outside the distortion of the earth's atmosphere.

Images can be found at http://www-solar.dcs.standrews.ac.uk/~eric/nature.html.
-end-


Montana State University

Related Corona Articles from Brightsurf:

BfR-Corona-Monitor: Respondents reduce contacts and stay at home more frequently
Starting this week, the new regulations for the containment of the coronavirus adopted by the Federal Government and the Länder will come into force throughout Germany.

Ban on accommodation meets with mixed acceptance among the population
The majority of the population considers the measures introduced by the Federal Government and the Länder to stem the spread of the coronavirus to be appropriate.

Corona-induced CO2 emission reductions are not yet detectable in the atmosphere
The impact of the corona pandemic will reduce worldwide carbon dioxide emissions by up to eight percent in 2020.

NASA's IRIS spots nanojets: Shining light on heating the solar corona
In a paper published today in Nature Astronomy, researchers report the first ever clear images of nanojets -- bright thin lights that travel perpendicular to the magnetic structures in the solar atmosphere, called the corona -- in a process that reveals the existence of one of the potential coronal heating candidates: nanoflares.

Despite coronavirus: Social contacts increase again
Arrange a get-together with friends, enjoy life out in the fresh air: Despite the corona pandemic, everyday life is returning to normal.

Rethinking business: Disruptions like the corona crisis also create new opportunities
Study analyses importance of historical times of change and the significance of disruptions for new success strategies.

Massive halo finally explains stream of gas swirling around the Milky Way
Astronomers at the University of Wisconsin-Madison and their colleagues have discovered that a halo of warm gas surrounding the Magellanic Clouds likely acts as a protective cocoon, shielding the dwarf galaxies from the Milky Way's own halo and contributing most of the Magellanic Stream's mass.

Apps and social distancing: Why we accept corona rules - or not
Study in psychology explores which factors are related to our motivation to use corona apps and to perform social distancing.

"Hotspots" of a corona infection in the human body
An infection with the coronavirus SARS-CoV-2 can affect multiple organs.

Vast majority supports mandatory corona tests for returnees
Should people who come to Germany from risk areas be tested for the novel coronavirus?

Read More: Corona News and Corona Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.