jump to navigation

Solar eruption aimed at Earth February 17, 2011

Posted by jcconwell in Astronomy, Solar and Space weather, stars.
Tags: , , ,
trackback

We are coming off the bottom of the 11 year sunspot cycle, so the sun is getting more active. As the internal magnetic field of the sun winds up, the field bursts out of the surface in regions known as sunspots.  Sunspots are cooler regions, hence they look darker, on the solar surface that have large magnetic fields. They can form in groups, and as part of their dynamics, they can release solar flares . Sunspot 1158 is a group of 4 sunspots that just had such a flare. The eruption can be seen in the video above taken by the SDO satillite and the optical image is below.

SOHO image from 2/17/2012

Sunspot 1158 in the lower right (OHO image from 2/17/2012)

Two forms of radiation come from an eruption, the electromagnetic radiation arrives first, just 500 seconds after the eruption. Then come the particles (mostly protons, with some Helium nuclei ) called the solar mass ejection. Since the particles travel much slower it can take up to several days to get to the Earth …and that is only if the spots are aimed at us.

The Chinese have reported some disruption in shortwave radio traffic. Very intense flares can cause damage to some satellites and power grids. This one however should just produce a light show, the aurora for people in more northern latitudes.

The NOAA space weather prediction site has aurora  maps to check if you can see the Northern lights.

Comments»

No comments yet — be the first.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: