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IMG src: thestar.com

By, Alex Knapp, Forbes Staff 

NASA reports that two massive solar flares erupted from the Sun yesterday, each paired with a Coronal Mass Ejection. The two CMEs are heading towards Earth and are expected to hit in the wee hours of the morning on March 8.  The first CME is travelling towards Earth at speeds greater than 1300 miles per second, and the second is travelling at about 1100 miles per second.  The sun is surrounded by intense magnetic fields, which is also known as its corona. Within the corona, occasionally two magnetic fields with opposite poles will come close to each other. When that happens, just like in magnets you might have at home, they will attract each other and connect. When that connection occurs, it releases huge amounts of energy, causing the Sun to eject tons of particles in the form of plasma. That’s the Coronal Mass Ejection. CMEs are often, but not always, accompanied by solar flares, which are huge ejections of radiation from the Sun. One of the two flares that erupted yesterday was classed as a X5.4 – making it the second largest solar flare in the current solar cycle.  The largest in this cycle erupted last summer.This afternoon, NASA estimated that the CMEs will collide with Earth at around 1:25 AM EST on the morning of March 8. When it collides with the Earth’s magnetic field, it will cause radioactive disruptions. Those disruptions, NASA warns, could affect high-frequency communications, interfere with GPS satellites, and could also potentially disrupt power grids. It should also create some stunning aurorae that might be visible in places that normally don’t get them.

These types of flares aren’t the end of the world – bigger solar events have hit the Earth in recent years, and the harms are usually minor.  There is a possibility that a powerful solar flare could cause serious harm to satellites, but such potential events are pretty rare. So if you’re out and around the time the CMEs hit, you might be lucky enough to catch an aurora, and you might not be able to post your location on Foursquare. But otherwise, life should go on pretty much as normal.

NASA has also produced a gorgeous video of the flare, which I’ve embedded below:


 
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By NED POTTER (@NedPotterABC)Feb. 28, 2012

There is an asteroid called 2011 AG5, and if it follows the orbit scientists have plotted for it so far, there is a small, small chance that it could hit Earth in February 2040.

Don't quit your job and sell your house just yet. Astronomers, who have been tracking the asteroid since January 2011, say it is in an elliptical orbit that could bring it somewhere near Earth in 2040. Earth is about 8,000 miles in diameter; the asteroid appears to be about 450 feet across.

The problem is that having watched it for only about half an orbit around the Sun, the scientists cannot say for certain where it will be 28 years from now. So, for the moment, NASA's Near Earth Object Program says the odds are about one in 625 that it could hit us in that still-distant future.

"We have a good opportunity to observe it next year and again in 2015," said Donald Yoemans, who heads the program at NASA's Jet Propulsion Laboratory. "We fully expect that the odds will go way down, most likely to zero, by then."

In the meantime, it was a subject of discussion at a meeting in Vienna of the Scientific and Technical Subcommittee of the United Nations Committee on the Peaceful Uses of Outer Space. The committee members agreed that 2011 AG5 bears watching, and could be useful as the subject of a "tabletop exercise" in what to do if, anytime soon, there really is an asteroid with our name on it."In our Action Team 14 discussions, we thus concluded that it not necessarily can be called a 'real' threat. To do that, ideally, we should have at least one, if not two, full orbits observed," said Detlef Koschny of the European Space Agency in an interview with Space.com

Scientists have discussed all sorts of far-out plans in case a future asteroid truly does turn out to be coming our way. If they have enough lead time, they might send a probe with thruster rockets, or even explosives, to nudge an asteroid into a slightly different orbit. A very small course change, years in advance, could make a big difference by 2040, they say. Even if the asteroid misses Earth by less than a hundred miles, its passing will be a non-event.

There are asteroids wandering around the inner solar system all the time -- one of them, called 2005 YU55, passed within 201,000 miles of Earth in November, closer than the moon is to us.

But about half a dozen times since the planet formed, there have been major for-real impacts with catastrophic results. The last, 65 million years ago, is believed to have killed off the last of the dinosaurs with the dust and ash that darkened the skies after it hit, though there have been scientists who disagree.

Scientists estimate that the asteroid from back then was about nine miles across at its widest, far larger than 2011 AG5. And they point out that they know very little about 2011 AG5; they cannot say whether it is a solid hunk of rock or a loose jumble of debris flying together in space. All they know is that it's in a long, elliptical orbit that takes it almost twice as far from the sun as we are.

"The bottom line is: We have time," Yoemans said. "The sober approach is to make more observations, to wait and see."

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