Saturday, September 16, 2017

Get a closer look at the big solar flares that keep coming

NASA’s Solar Dynamics Observatory, which watches the sun constantly, captured images of the events. Solar flares are powerful bursts of radiation.
Harmful radiation from a flare cannot pass through Earth's atmosphere to physically affect humans on the ground, however — when intense enough — they can disturb the atmosphere in the layer where GPS and communications signals travel.
To see how this event may affect Earth, please visit NOAA's Space Weather Prediction Center at http://spaceweather.gov, the U.S. government's official source for space weather forecasts, alerts, watches and warnings.
X-class denotes the most intense flares, while the number provides more information about its strength. An X2 is twice as intense as an X1, an X3 is three times as intense, etc.
The X9.3 flare was the largest flare so far in the current solar cycle, the approximately 11-year-cycle during which the sun’s activity waxes and wanes.
The current solar cycle began in December 2008, and is now decreasing in intensity and heading toward solar minimum.
This is a phase when such eruptions on the sun are increasingly rare, but history has shown that they can nonetheless be intense.

From CNET by Erik Mack

The sun should be quiet right now.
Instead, it's been shooting hot particles and plasma into space for the past week, to the delight of scientists.

Hot on the heels of the epic American total solar eclipse in August, our sun this month has followed up with what you might call totally cray behavior.
The biggest star around is supposed to be entering a phase of relatively little activity right now.
Yet it has spent the past week shooting off some of the biggest solar flares we've seen in over a decade.

The sun goes through 11-year cycles of solar activity, including a solar maximum when scientists expect to see the highest level of sunspots and solar flares.
But we passed that point in the current cycle in 2014 and are now approaching the solar minimum.
So it's a little surprising that a big sunspot has been shooting off a bunch of flares, including the biggest of the current cycle, for the past week.
A huge, so-called X-class flare (the highest level of intensity) was fired off Wednesday.
It released an amount of energy comparable to that of a billion hydrogen bombs and sent radiation and plasma soaring toward Earth that's not harmful to life thanks to our planet's atmosphere and magnetic field.
The solar storm can disrupt communications signals, however, and also fuels some pretty remarkable auroras
One X9.3 flare Wednesday was the strongest flare seen in over 12 years.
NASA's Solar Dynamics Observatory, which watches the sun continuously, caught a few different views of last week's flares that can be seen in the above video.
Scientists using a solar telescope on the Canary Islands also managed to capture a close-up view.

It’s always shining, always ablaze with light and energy that drive weather, biology and more.
In addition to keeping life alive on Earth, the sun also sends out a constant flow of particles called the solar wind, and it occasionally erupts with giant clouds of solar material, called coronal mass ejections, or explosions of X-rays called solar flares.
These events can rattle our space environment out to the very edges of our solar system.
In space, NASA’s Solar Dynamics Observatory, or SDO, keeps an eye on our nearest star 24/7.
SDO captures images of the sun in 10 different wavelengths, each of which helps highlight a different temperature of solar material.
In this video, we experience SDO images of the sun in unprecedented detail.
Presented in ultra-high definition, the video presents the dance of the ultra-hot material on our life-giving star in extraordinary detail, offering an intimate view of the grand forces of the solar system.

"The sun is currently in what we call solar minimum. The number of Active Regions, where flares occur, is low, so to have X-class flares so close together is very unusual," said Aaron Reid, a research fellow at Queen's University Belfast, in a news release.
"These observations can tell us how and why these flares formed so we can better predict them in the future."
A total of three X-class flares were observed over a 48-hour period, along with medium-intensity flares that went off earlier last week,  and another, just slightly less intense X-class flare on Sunday.
While the flare activity of the past week has been unusual and unexpected, it seems likely to come to an end soon.
The big sunspot responsible for the flares is about to disappear from view as part of the star's normal rotation.

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