February 3, 2013

Flux Ropes Help Scientists Understand CMEs

[ Watch the Video: An Earth-directed Coronal Mass Ejection (CME) on Jan. 31, 2013 ]

Coronal mass ejections (CMEs) are easier to define than understand, but NASA’s Solar Dynamics Observatory (SDO) is helping to put an end to that.

CMEs take place on the sun and are essentially big bursts of plasma, creating a magnetic loop on the sun, and shooting out billions of tons of solar material while it does so.

Pictures taken by SDO on July 18, 2012 have helped scientists at NASA get a better understanding of these very-photogenic events on our home star. This event allowed scientists to witness, for the first time, the formation of a flux rope.

A flux rope is a series of loops that lies at the heart of the eruptions on the sun, and Angelos Vourlidas, a solar scientist at the Naval Research Laboratory in Washington, D.C, says that witnessing one looks exactly like the cartoon sketches theorists have been drawing.

“Seeing this structure was amazing,” Vourlidas said in a statement. “It was a series of figure eights lined up to look like a giant slinky on the sun.”

Flux ropes have been seen in images of CMEs, but its never been known whether they formed before or in conjunction with the eruption. The SDO images give more information into this understanding.

Dean Pesnell, the project scientist for SDO at NASA’s Goddard Space Flight Center, said that witnessing these flux ropes will give scientists a better way to predict CMEs, telling them when and where they will erupt.

Having this kind of ability to predict CMEs will really help scientists be better equipped to predict space weather as well. Essentially, space weather is a result of the sun’s activity, and large CME events directed towards Earth and can have an impact on our astronauts onboard the International Space Station, as well as satellite communications in orbit.

In order to spot the flux rope, the team said they had to go back in time a few minutes, then an hour, then eight years. Next, the sun helped to provide the perfect angle at which to see the flux rope. Lastly, cameras looking at the sun in the 131 Angstrom wavelength gave scientists the goggles they needed.

As the flux rope formed, it showed up faintly in images of cooler material, which let NASA scientists know that the material from the flare cooled down over time as the flux rope rose in space. Eight hours later, NASA said the material got hot again, the region flared, and the flux rope jutted off into space.

“It’s a wonderful time to be a solar physicist, because thanks to the large number of telescopes we have in space at the moment, we can see things like this from every angle,” said Vourlidas.

NASA’s Solar Terrestrial Relations Observatory (STEREO) aided the team as well, giving them a look at the 3D structure of the rope.

Now, the team will be scouring evidence for more examples of the flux ropes, helping to refine and improve the theories as to what causes CMEs.

Image Credit: NASA / SDO / Goddard Space Flight Center

Facebook Twitter Pinterest Plusone Digg Reddit Stumbleupon Email