Tuesday, 16 July 2013

NASA scientists see the heart of space weather in action

Magnetic reconnection occurs when magnetic field lines come together, break apart, and then exchange partners, snapping into place with a bolt of energy



Photo credit: NASA/SDO/RHESSI/Goddard


Science Recorder | Ellen Miller | Tuesday, July 16, 2013


Two spacecraft have captured a video of a magnificent explosion on the Sun called magnetic reconnection. Magnetic reconnection lies at the heart of explosions that occur on the surface of the Sun, a press release from NASA explains.

Magnetic reconnection occurs when magnetic field lines come together, break apart, and then exchange partners, snapping into place with a bolt of energy. Scientists at space research agencies such as NASA are seeking to better understand phenomena like magnetic reconnection because they hope that it will aide them in understanding and predicting space weather, which can affect satellites and radio communication. Because magnetic fields are invisible, it can be difficult to observe them in action.

Yang Su, a solar scientist at the University of Graz in Austria, explains that scientists are specifically seeking to understand how magnetic reconnection can cause solar flares. Scientists use computer modeling and a few observations about magnetic reconnection to try to understand this concept, but thanks to new video from two spacecraft, they will be able to take a more in-depth look at magnetic reconnection. Su discovered direct images of magnetic reconnection while looking through data from the Solar Dynamics Observatory. While a few images have been discovered before, this is the first comprehensive set that will really aide scientists in understanding what is happening when magnetic reconnection occurs and how it impacts solar and space weather.


While magnetic field lines are invisible, they force charged particles of plasma along their lengths, making them visible in images. Space telescopes pick up the lines as they arch and move along the frame of the lens. Su observed two bundles of lines move towards each other and then disconnect and reconnect.

The video offers scientists an entirely new resource since it allows them to see the phenomena in recorded time and animated, as opposed to simple photos that only offer an indication of what is happening. The team, led by Su, turned to the Reuven Ramaty High Energy Solar Spectroscopic Imager, known as RHESSI, to confirm that they were actually observing magnetic reconnection in action. RHESSI shows where hot pockets are, indicating where space weather is occurring. By combining the data, scientists were able to describe the entire process of magnetic reconnection, confirming many theories about the process as well as learning new information that they were able to observe for the first time.

Magnetic reconnection does not only occur on the surface of the sun, it also occurs near stars and within Earth’s own magnetic field, making it a key player in space weather patterns.




Read more: http://www.sciencerecorder.com/news/nasa-scientists-see-the-heart-of-space-weather-in-action/#ixzz2ZDyV86sf

No comments:

Post a Comment