Archive for NOAA forecasters

After a long, long summer day, Arctic skies are darkening again, and in the sunset observers are seeing rays of green in the twilight blue

Posted in 2014, astronomy with tags , , , , on August 31, 2014 by MARIE EMMANUELLE QUILICHINI

sunsetauroras_strip

“I went out last night to catch the sunset–but mostly the auroras,” says Olsen. “Even before it was dark, the Northern Lights made an appearance.”

More lights are in the offing. NOAA forecasters estimate a 20% of polar geomagnetic storms during the next 24 hours. The odds of Arctic auroras are higher, however, because it doesn’t take a full-fledged storm to turn the twilight green at polar latitudes. Now is a good time to book a tour. Aurora alerts: text, voice

http://spaceweather.com/

M7-CLASS SOLAR FLARE : Sunspot AR2036 erupted on April 18th at 1307 UT, producing a strong M7-class solar flare. 

Posted in 2014 with tags , , , , , , , , , on April 19, 2014 by MARIE EMMANUELLE QUILICHINI

An S1-class radiation storm is underway in the aftermath of the flare. However, this is a relatively minor storm which poses minimal threat to satellites and aircraft.

Of greater interest is a CME that emerged from the blast site. The Solar and Heliospheric Observatory recorded the storm cloud racing away from the sun at aproximately 800 km/s:

cme_anim

This CME could deliver a glancing blow to Earth’s magnetic field on April 20-21. Two or three minor CMEs traveling ahead of this one are expected to arrive on April 19-20, and the combined impacts could generate geomagnetic activity throughout the weekend. NOAA forecasters put the odds of a geomagnetic storm at 55% on Saturday, increasing to 75% on Sunday. High-latitude sky watchers should be alert for auroras. Solar flare alerts: textvoice

http://spaceweather.com/

CORONAL HOLES: NASA’s Solar Dynamics Observatory is monitoring a pair of coronal holes straddling the sun’s equator.

Posted in 2014 with tags , , , , , , , on April 10, 2014 by MARIE EMMANUELLE QUILICHINI

 They are the deep-blue wedges in this extreme ultraviolet image of the sun taken mid-day on April 9th:

Coronal holes are places in the sun’s atmosphere where the ambient magnetic field opens up and allows solar wind to escape. A double-stream of solar wind flowing from these coronal holes could reach Earth on April 12-14.

It is possible that neither stream will be geoeffective as they flow north and south of our planet. On the other hand, a “brush pass” might still spark polar auroras. NOAA forecasters estmate a 40% chance of polar geomagnetic storms when the streams arrive. Aurora alerts:textvoice

http://spaceweather.com/

Solar Flares : A Second X-Class Flare Erupted on the Sun in less than a month

Posted in Uncategorized with tags , , , , , , , , , , on March 10, 2011 by MARIE EMMANUELLE QUILICHINI

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