Geomagnetic storm subsiding

Apr 14, 2011 by Tony Phillips/Holly Zell
A sky watcher from Marquette, Michigan took this photo before sunrise today. Credit: NASA/Shawn Malone

A geomagnetic storm that sparked auroras around the Arctic Circle and sent Northern Lights spilling over the Canadian border into the United States on April 12, 2011 is subsiding. NOAA forecasters estimate a 25% chance of more geomagnetic activity during the next 24 hours.

What is a geomagnetic storm?

The Earth's is created by our magnetic field and protects us from most of the particles the emits. When a CME or high-speed stream arrives at Earth it buffets the magnetosphere. If the arriving solar magnetic field is directed southward it interacts strongly with the oppositely oriented magnetic field of the Earth. The Earth's magnetic field is then peeled open like an onion allowing energetic solar wind particles to stream down the field lines to hit the over the poles. At the Earth's surface a magnetic storm is seen as a rapid drop in the Earth's magnetic field strength. This decrease lasts about 6 to 12 hours, after which the magnetic field gradually recovers over a period of several days.

Here's another great aurora image from Fairbanks, Alaska. Credit: NASA/Warren Gammel


Explore further: Cassini sees sunny seas on Titan

add to favorites email to friend print save as pdf

Related Stories

Aurora alert: The Sun is waking up (w/ Video)

Aug 02, 2010

Sky viewers might get to enjoy some spectacular Northern Lights, or aurorae, tomorrow. After a long slumber, the Sun is waking up. Early Sunday morning, the Sun's surface erupted and blasted tons of plasma ...

Recommended for you

Cassini sees sunny seas on Titan

13 hours ago

(Phys.org) —As it soared past Saturn's large moon Titan recently, NASA's Cassini spacecraft caught a glimpse of bright sunlight reflecting off hydrocarbon seas.

Is space tourism safe or do civilians risk health effects?

16 hours ago

Several companies are developing spacecraft designed to take ordinary citizens, not astronauts, on short trips into space. "Space tourism" and short periods of weightlessness appear to be safe for most individuals ...

An unmanned rocket exploded. So what?

19 hours ago

Sputnik was launched more than 50 years ago. Since then we have seen missions launched to Mercury, Mars and to all the planets within the solar system. We have sent a dozen men to the moon and many more to ...

NASA image: Sunrise from the International Space Station

20 hours ago

NASA astronaut Reid Wiseman posted this image of a sunrise, captured from the International Space Station, to social media on Oct. 29, 2014. Wiseman wrote, "Not every day is easy. Yesterday was a tough one. ...

Copernicus operations secured until 2021

21 hours ago

In a landmark agreement for Europe's Copernicus programme, the European Commission and ESA have signed an Agreement of over €3 billion to manage and implement the Copernicus 'space component' between 2014 ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.