Archive for Coronal Holes

NASA’s Solar Dynamics Observatory (SDO) is monitoring a hole in the sun’s atmosphere–a “coronal hole.”

Posted in 2015, astronomy, Galaxy with tags , , , , , on August 26, 2015 by MARIE EMMANUELLE QUILICHINI

sun_hole

It is colored deep-blue in this extreme UV image of the sun taken by SDO on Aug. 26th

CLICK HERE ON LINK TO SEE FULL IMAGE AND ZOOM ON IT

http://www.spaceweather.com/images2015/26aug15/ch.jpg?PHPSESSID=ajitmknl5666rvrf1cpbab5ia4

Coronal holes are places where the sun’s magnetic field opens up and allows solar wind to escape. In the image, above, the sun’s magnetic field is traced by pale loops. White arrows show the flow of material out of the hole.

A stream of solar wind flowing from this coronal hole will probably reach Earth on Aug. 28-29. Its impact could spark a geomagnetic storm at the end of this week. If so, bright moonlight will temper the visibility of any auroras. Aurora alerts: text or voice

http://www.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/

%d bloggers like this: