Christ First Forum

http://www.accuweather.com/blogs/news/s ... 0.facebook




After the southern U.S. got a rare view of northern lights last week, the potential is increasing for more of the world to catch a glimpse over the next two weeks.

Behind what promises to be a spectacular show, along with the threat of communication disruptions, is an unusually large sunspot that will face Earth in upcoming days.

Spaceweather.com states that this sunspot, labeled AR1339, is one of the biggest in many years.

The sunspot measures nearly 25,000 miles wide and close to 50,000 miles long. "Two or three of the sunspot's dark cores are wider than Earth itself," reported Spaceweather.com.

While saying that the sunspot "is not the granddaddy of them all," Joe Kunches from NOAA's Space Weather Prediction Center told AccuWeather.com that NOAA is very interested in it.

The sunspot will remain visible from Earth over the next two weeks as it rotates eastward with the sun, ready to erupt anytime beyond Friday.

An eruption does not necessarily translate to enhanced northern lights (called southern lights in the Southern Hemisphere).

Every eruption produces a solar flare, but a coronal mass ejection, or CME (a cloud of charged particles), must follow in order for the Earth to witness a magnificent light show or face communication disruptions.

Kunches states that in some cases a CME is never produced.

Even if a CME occurs, it may not head to Earth, as was the case with the eruption that took place Thursday. With the sunspot situated on the sun's outer edge (from Earth's viewing point), the CME took aim on Mercury and Venus instead.

The Earth has a better chance at feeling the effects of a CME as the sunspot rotates with the sun and faces toward Earth.

The sunspot will have its greatest aim toward Earth in about four or five days, according to Kunches.

If an eruption occurs and an Earth-bound CME is produced, Kunches reports that it could reach the planet in as little as 18 hours, or as long as three or four days.

The strength of the eruption determines the speed of the CME, which NOAA can calculate based on observational tools currently in place.

From these calculations, NOAA can then estimate when the CME will reach Earth. The accuracy of such predictions, according to Kunches, has improved to within five hours of its actual arrival.

AccuWeather.com Astronomy Blogger Mark Paquette will continue to provide updates on any eruptions over the next two weeks.

In the event a CME is expected to reach Earth, be sure to check your local AccuWeather.com forecast to find out if rain, snow or clouds will obscure your view of what promises to be a magnificent light show.