25Sep2012

Shedding “Sunlight” On CMEs.

A computer visualization of the sun (red sphere) and its magnetic field lines (orange and aquamarine). The close-up shows the final stage of the emergence of magnetic fields from under the solar surface and the associated X-ray emissions. This sophisticated computer model is used to investigate the drivers of harmful space weather phenomena, including coronal mass ejections. Image courtesy of Cooper Downs, Predictive Science, Inc.

For forty years solar physicists have been endeavoring to both understand and explain the Sun’s dynamic explosions known as Coronal Mass Ejections (CMEs). These staggering events erupt from the Sun at speeds of over a million miles per hour and unleash more energy than the Earth’s combined arsenal of nuclear weapons. However, what causes these huge clouds of hot gas and charged particles? Why does the plasma and magnetic fields literally explode from the Sun? 

For those interested in the dynamics of astronomy, we’re aware of the astounding affects that a coronal mass ejection can cause in terms of space weather. They don’t just stop at Earth-orbiting satellites… they can even impact terrestrial power grids and more. Now a team of international space scientists, including a researcher from the University of New Hampshire’s Space Science Center (SSC), have published a paper in “Nature Physics” which diagrams the physical mechanisms speculated to be the origin of CMEs. Through the use of computer simulations, the researchers show the detailed connection between these events and the turbulent environment of the Sun’s interior. These new findings could lead to improvement of better space weather forecasting techniques – especially the dangerous ones.

Coronal Mass Ejection: Artist Concept (NASA, Sun)

Coronal Mass Ejection: Artist Concept (NASA, Sun) (Photo credit: NASA's Marshall Space Flight Center)

“By studying CMEs we learn not only about the drivers of space weather but also about the structure of the atmosphere of the Sun and other Sun-like stars,” says lead author Ilia Roussev of the Yunnan Astronomical Observatory, Chinese Academy of Sciences (CAS) and the Institute for Astronomy at the University of Hawaii at Manoa.

Space scientists don’t take CMEs lightly – especially when they are aimed towards Earth. Intense geomagnetic storms are harmful to astronauts in space, can interfere communications and GPS satellites, reroute airline flights over polar regions and disable power grids. Despite their destructive force, coronal mass ejections can also be things of beauty – creating spectacular auroral activity.

According to the news release, the Nature Physics paper, titled “Explaining fast ejections of plasma and exotic X-ray emission from the solar corona,” provides an explanation of the origin of fast ejections of magnetized plasma from the Sun’s atmosphere and associated X-ray emissions. It thus demonstrates a fundamental connection between the magnetic processes inside the Sun’s interior and the formation of CMEs.

“Through this type of computer modeling we are able to understand how invisible bundles of magnetic field rise from under the surface of the Sun into interplanetary space and propagate towards Earth with potentially damaging results”, says SSC researcher Noé Lugaz of the UNH Institute for the Study of Earth, Oceans, and Space. He adds, “These fundamental phenomena cannot be observed even with the most advanced instruments on board NASA satellites but they can be revealed by numerical simulations.”

For now, the solar physicists will continue to refine their computer simulations and do their best to upgrade the forecasting of extreme solar activity and what impacts it could have on Earth. In the paper, the authors note, “the model described here enables us not only to capture the magnetic evolution of the CME, but also to calculate the increased X-ray flux directly, which is a significant advantage over the existing models.”

Original Story Source: University of New Hampshire News Release. Reported by: Tammy Plotner for “Dave Reneke’s World of Space and Astronomy”

Read previous post:
Shine On Harvest Moon Now!

Harvest Moon Shines This Weekend. THE HARVEST MOON is coming...

Amazing Video – Fly Beside A Space Shuttle

Fly Over California Alongside a Space Shuttle!  We’ve shared several...

Telescope Amnesty A Great Success

Telescope Amnesty A Great Success Here's what it looked like...

Close