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July 19, 2018, 12:00 Washington, July 19 (Prensa Latina) American solar physicists first detected fine-grained structures in the outer ring of the sun, making it more dynamic It was previously thought previously published today by The Astrophysical Journal
Previous images of the corona showed that the region was a smooth, laminar structure because of the limitations of its resolution, so
Longer exposures allow more light to enter the detector and reduce the noise level, which is estimated at a factor of 2.4 for each image, and 10 when they combine in a period of 20 minutes, said Nicki Viall, solar physicist at NASA (National Aeronautics and Space Administration) .
In order to improve the signal-to-noise ratio, scientists have developed sophisticated algorithms tested to extract the true crown of noisy measurements.
They filtered the light from the background stars, corrected by small differences (of a few milliseconds) how long it was open to the camera shutter, they eliminated the brightness of the baseline of all the images and have it normalized so that the brightest regions do not move the weaker ones.
One of the obstacles was the blur caused by the solar wind. To overcome this source of noise, researchers had to soften their images in time
The most surprising discovery in this sense was not a specific physical structure, but the mere presence of the physical structure itself .
the dynamic and turbulent inner crown, the scientists considered that the outer crown was smooth and homogeneous, but that the softness was only an artifact of low signal-to-noise ratio.
The results obtained are a harbinger of what Parker could see Solar Probe (spacecraft projected by NASA to orbit the Sun), which, after its launch this summer, will orbit directly across the region.
mgt / ml
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