October 21, 2012
Sun Unleashes Spectacular Solar Plasma Wave
April Flowers for redOrbit.com - Your Universe Online
NASA´s Solar Dynamics Observatory captured a spectacular solar eruption on Friday. A giant super-hot wave of solar plasma larger than the planet Earth erupted from the Sun at 4:15 a.m. EDT and was caught in amazing high-definition detail by the NASA spacecraft."Once it started breaking away, the process only took 10 hours before it was out of sight," NASA media specialist Steele Hill explained in a photo description. "The prominence stretched out many times the size of Earth."
The solar prominence showed as a wispy red-orange wave that stretched out from the lower right section of the sun. According to Hill, the image was recorded in the 304 Angstrom wavelength of extreme ultraviolet light.
A prominence is an eruption of charged solar plasma that appears to arc out away from the Sun's edge, or limb, in the views of telescopes and spacecraft. Extreme magnetic fields give the structures shape. Loop shaped prominences are short-lived, lasting only a few minutes, while others can be more stable — lasting hours or even days.
The Solar Dynamics Observatory, along with other spacecraft, tracks major solar flares, eruptions and other space weather events. The Sun has an 11-year weather cycle and is currently in a very active phase, which is expected to reach its peak in 2013.
This cycle has been designate Solar Cycle 24. The Solar Dynamics Observatory has been tracking the Sun's weather activity since 2010.
What do scientists do with these images, though? Sometimes, you have to mix a little art with your science to really see what is going on. Science and art seem to be at the opposite ends of the spectrum, but in many ways, they depend on each other. Science and art techniques are often informed by each other. One such example is with a technique called "gradient filter." Many who use photo-editing programs will be familiar with this technique.
A gradient is a mathematical description that highlights the places of greatest change in space. In turn, a gradient filter enhances places of contrast, making them more obviously different. This is a useful tool when adjusting photographs.
Scientists also enhance contrast using gradient filters to accentuate fine structures that might otherwise be lost in the background noise. For example, scientists studying the sun are interested in a phenomenon called coronal loops, which are giant arcs of solar material constrained to travel along that particular path by the magnetic fields in the sun's atmosphere. The loops vary in complexity as the Sun goes through its 11-year cycle, moving between more and less intertwined. Observing this phenomenon allows researchers to understand the sun's complicated magnetic fields and how they contribute power to the massive eruptions like solar flares, or coronal mass ejections. Using a gradient filter makes these structures sharp and defined, all the more easy to study.
Deciding which techniques to use and how best to process scientific imagery takes a collaboration of experts working together to devise new and improved methods. For the last nine years, a diverse group of scientists including experts in statistics, computer recognition and image processing has come together at Solar Information Processing workshops specifically to focus on state-of-the-art imaging techniques to further scientific research.