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Showing posts with label Science News. Show all posts
Showing posts with label Science News. Show all posts

Thursday, March 08, 2012

Strong solar storm heading for Earth

Strong solar storm heading for Earth
Largest solar flares of this solar cycle in this NASA photo taken on March 6, 2012
(Reuters) - A strong geomagnetic storm is racing from the Sun toward Earth, and its expected arrival on Thursday could affect power grids, airplane routes and space-based satellite navigation systems, U.S. space weather experts said.

The storm, a big cloud of charged particles flung from the Sun at about 4.5 million miles per hour (7.2 million km per hour), was spawned by a pair of solar flares, scientists said.

This is probably the strongest such event in nearly six years, and is likely more intense than a similar storm in late January, said Joseph Kunches, a space weather specialist at the U.S. National Oceanic and Atmospheric Administration (NOAA).

This solar disturbance is a three-stage affair, or as Kunches said in a telephone interview from Boulder, Colorado: "We hit the trifecta."

These are the stages he described, with the first two already affecting Earth:

* First, two solar flares moving at nearly the speed of light reached Earth late on Tuesday. Such flares can cause radio blackouts.

* Then, solar radiation hit Earth's magnetic field on Wednesday, with possible impact on air traffic, especially near the poles, satellites and any astronauts taking space walks. This phase could last for days.

* Finally, the plasma cloud sent by the coronal mass ejection, which is basically a big chunk of the Sun's atmosphere, is expected to arrive at Earth early on Thursday.

This phase can disrupt power grids, satellites, oil pipelines and high-accuracy GPS systems used by oil drillers, surveyors and some agricultural operations, scientists said.

GPS systems used for less-refined functions, such as the turn-by-turn navigation found in many cars, should not be affected, according to NOAA's Doug Biesiecker.

Kunches said the geomagnetic component of the storm may arrive a bit ahead of schedule because it follows a previous storm that left the Sun on Sunday and is currently buffeting the Earth's magnetosphere.

"When you've already had one coronal mass ejection storm, sometimes the next coronal mass ejection storm is faster to get here," Kunches said.

These storms could produce some vivid auroras, according to experts. In the Northern Hemisphere, the aurora borealis could be visible at mid-latitudes, which in the United States could include New York, Illinois and Iowa.

Such stormy space weather is unusual in recent history, according to Harlan Spence, an astrophysicist at the University of New Hampshire who is principal investigator on the Cosmic Ray Telescope for the Effects of Radiation (CRaTER) aboard NASA's Lunar Reconnaissance Orbiter.

"These relatively large (solar) events, which we've had maybe a couple of handfuls total in the course of a decade, we've now had two or three of them, more or less right on top of each other," Spence said by telephone.

The Sun is on the ascendant phase of its 11-year cycle of solar activity, with the peak expected next year, scientists said.

"It's a clear harbinger that the Sun is waking up," Spence said. "We're trying to put this in context not only ... of what has the Sun done in the past, but what is the biggest thing the Sun is capable of and what should we be planning for in terms of extreme sorts of events in the future."

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Tuesday, January 24, 2012

Solar Storm Now Hitting Earth, Called Strongest Since 2005, Could Affect Astronauts

Solar Storm, Nasa
A View of Solar Storm on the surface of blazing Sun
WASHINGTON -- The sun is bombarding Earth with radiation from the biggest solar storm in more than six years with more to come from the fast-moving eruption.

The solar flare occurred at about 11 p.m. EST Sunday and will hit Earth with three different effects at three different times. The biggest issue is radiation, according to the National Oceanic and Atmospheric Administration's Space Weather Prediction Center in Colorado.

The radiation is mostly a concern for satellite disruptions and astronauts in space. It can cause communication problems for polar-traveling airplanes, said space weather center physicist Doug Biesecker.

Radiation from Sunday's flare arrived at Earth an hour later and will likely continue through Wednesday. Levels are considered strong but other storms have been more severe. There are two higher levels of radiation on NOAA's storm scale – severe and extreme – Biesecker said. Still, this storm is the strongest for radiation since May 2005.

The radiation – in the form of protons – came flying out of the sun at 93 million miles per hour.

"The whole volume of space between here and Jupiter is just filled with protons and you just don't get rid of them like that," Biesecker said. That's why the effects will stick around for a couple days.

NASA's flight surgeons and solar experts examined the solar flare's expected effects and decided that the six astronauts on the International Space Station do not have to do anything to protect themselves from the radiation, spokesman Rob Navias said.

A solar eruption is followed by a one-two-three punch, said Antti Pulkkinen, a physicist at NASA's Goddard Space Flight Center in Maryland and Catholic University.

First comes electromagnetic radiation, followed by radiation in the form of protons.

Then, finally the coronal mass ejection – that's the plasma from the sun itself – hits. Usually that travels at about 1 or 2 million miles per hour, but this storm is particularly speedy and is shooting out at 4 million miles per hour, Biesecker said.

It's the plasma that causes much of the noticeable problems on Earth, such as electrical grid outages. In 1989, a solar storm caused a massive blackout in Quebec. It can also pull the northern lights further south.

But this coronal mass ejection seems likely to be only moderate, with a chance for becoming strong, Biesecker said. The worst of the storm is likely to go north of Earth.

And unlike last October, when a freak solar storm caused auroras to be seen as far south as Alabama, the northern lights aren't likely to dip too far south this time, Biesecker said. Parts of New England, upstate New York, northern Michigan, Montana and the Pacific Northwest could see an aurora but not until Tuesday evening, he said.

News by Huffingtonpost


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