NASA Spacecraft Observes New Characteristics Of Solar Flares

[NASA News <hqnews@xxxxxxxxxxxxxxxxxxxxxx>]

Sep. 07, 2011

Steve Cole                                
Headquarters, Washington                      
202-358-0918 
stephen.e.cole@xxxxxxxx 

Susan Hendrix                                
Goddard Space Flight Center, Greenbelt, Md.                     
301-286-7745 
susan.m.hendrix@xxxxxxxx 

RELEASE: 11-291

NASA SPACECRAFT OBSERVES NEW CHARACTERISTICS OF SOLAR FLARES

WASHINGTON -- NASA's Solar Dynamics Observatory, or SDO, has provided 
scientists new information about solar flares indicating an increase 
in strength and longevity that is more than previously thought. 

Solar flares are intense bursts of radiation from the release of 
magnetic energy associated with sunspots. They are the solar system's 
largest explosive events and are seen as bright areas on the sun. 
Their energy can reach Earth's atmosphere and affect operations of 
Earth-orbiting communication and navigation satellites. 

Using SDO's Extreme ultraviolet Variability Experiment (EVE) 
instrument, scientists have observed that radiation from solar flares 
continue for up to five hours beyond the main phase. The new data 
also show the total energy from this extended phase of the solar 
flare's peak sometimes has more energy than the initial event. 

"Previous observations considered a few seconds or minutes to be the 
normal part of the flare process," said Lika Guhathakurta, lead 
program scientist for NASA's Living with a Star Program at the 
agency's Headquarters in Washington. "This new data will increase our 
understanding of flare physics and the consequences in near-Earth 
space where many scientific and commercial satellites reside." 
On Nov. 3, 2010, SDO observed a solar flare. If scientists only had 
measured the effects of the flare as it initially happened, they 
would have underestimated the amount of energy shooting into Earth's 
atmosphere by 70 percent. SDO's new observations provide a much more 
accurate estimation of the total energy solar flares put into Earth's 
environment. 

"For decades, our standard for flares has been to watch the X-rays as 
they happen and see when they peak," said Tom Woods, a space 
scientist at the University of Colorado in Boulder and principal 
author on a paper in Wednesday's online edition of Astrophysical 
Journal. "But we were seeing peaks that didn't correspond to the 
X-rays." 

During the course of a year, the team used EVE to map each wavelength 
of light as it strengthened, peaked, and diminished over time. EVE 
records data every 10 seconds and has observed many flares. Previous 
instruments only measured every 90 minutes or didn't look at all 
wavelengths simultaneously as SDO can. 

To compliment the EVE graphical data, scientists used images from 
another SDO instrument, the Advanced Imaging Assembly (AIA). Analysis 
of these images showed the main flare eruption and its extended phase 
in the form of magnetic field lines called coronal loops that 
appeared far above the original eruption site. These extra loops were 
longer and became brighter later than the loops from the main flare 
and also were physically set apart from those of the main flare. 

Because this previously unrealized extra source of energy from flares 
also is impacting Earth's atmosphere, Woods and his colleagues are 
studying how the late phase flares can influence space weather. Space 
weather caused by solar flares can affect communication and 
navigation systems, satellite drag and the decay of orbital debris. 

SDO was launched on Feb. 11, 2010. The spacecraft is the most advanced 
spacecraft ever designed to study the sun and its dynamic behavior. 
SDO provides images 10 times clearer than high definition television 
and more comprehensive science data faster than any solar observing 
spacecraft in history. 

EVE was built by the Laboratory for Atmospheric and Space Physics at 
the University of Colorado. AIA was built by Lockheed Martin Solar 
and Astrophysics Laboratory in Palo Alto, Calif. 

NASA's Goddard Space Flight Center in Greenbelt, Md., built, operates 
and manages the SDO spacecraft for NASA's Science Mission Directorate 
in Washington. SDO is the first mission of NASA's Living with a Star 
Program, or LWS. The goal of LWS is to develop the scientific 
understanding necessary to address those aspects of the connected 
sun-Earth system that directly affect our lives and society. 

For more information and images, visit: 



http://www.nasa.gov/sunearth 


For more information about the SDO mission and instruments, visit: 



http://www.nasa.gov/sdo 

	
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