Thursday 2 December 2010

NEW SUNSPOT: A sunspot is emerging over the sun's northeastern limb, and it appears to be one of the largest of the new solar cycle. This composite image from NASA's Solar Dynamics Observatory shows the sunspot's dark core (inset) and plumes of plasma shooting up from the active region: link
It is too soon to say whether this sunspot poses a threat for strong solar flares. At the moment we are seeing the region almost edge-on, so the sunspot's magnetic field (the source of flares) is not fully available for inspection. One thing is certain: It's photogenic. Readers with backyard solar telescopes are encouraged to monitoor developments.

Solar flares could cause British black-outs, MPs are warnedlink

Solar flares could cause power cuts affecting Britain's electricity grid and communication networks, MPs were warned yesterday.

Solar flares could cause power cuts affecting Britain's electricity grid and communication networks
Solar flares could cause power cuts affecting Britain's electricity grid and communication networks Photo: NASA/REUTERS
Security minister Baroness Neville-Jones said there "must be some risk" to the electricity network when the sun's activity peaks around 2013 as part of an 11-year cycle. The threat of disruption grows during each cycle due to our increasing reliance on electricity.
The National Grid is already undertaking a study - due for publication in the spring - to determine the vulnerability of the network, she told the House of Commons Science and Technology Committee.
The report was commissioned after Dr Liam Fox, the Defence Secretary, warned in September that possible threats to the nation's hi-tech infrastructure, including solar activity, need to be addressed.
The prospect of widespread black-outs caused by a once-in-a-century solar flares was raised by Nasa scientists in June.
Some scientists believe that a disturbance on the sun's surface could cause geomagnetic storms on earth that could cause disruption similar to that if a nuclear weapon was detonated in space.
It could damage everything from emergency services’ systems, hospital equipment, banking systems and air traffic control devices, through to “everyday” items such as home computers, iPods and Sat Navs.
Lady Neville-Jones told the cross-party committee: "We have been forewarned, in the sense that the sunspot cycle is coming to a peak and it looks as though it's going to be a fairly vigorous peak.
"It therefore behoves us to have laid very good ground for that.
"If you get vigorous space weather, and you do in particular get spikes in the solar cycle, it can clearly affect in particular communications."
Lady Neville-Jones said the UK Space Agency was being used as a source of expertise on the forthcoming peak in the solar cycle, as well as a means of keeping in touch with the best informed experts overseas.
Science minister David Willetts said that private sector operators of "vulnerable" communications satellites were also being involved in planning for the event.
Asked whether the National Grid was at risk, Lady Neville-Jones replied: "There must be some risk. What we don't yet know... is how big it is."
She added: "My feeling is there must be some risk. A lot depends on how many overhead lines you have got, how much you bury it underground and specific vulnerabilities such as when the power lines come from underwater on to land. We need to do - and this is what the National Grid is doing - a study on the specific details on UK conditions."
The number of sunspots - dark patches on the surface of the Sun, produced by intense magnetic fields and cooler than surrounding areas - is used to measure the state of solar magnetic activity.
The magnetic activity cycle, which generally follows an 11-year pattern of peaks and troughs, drives variations in the level of ultra-violet light reaching Earth, which is thought to have an impact on radio signals and possibly terrestrial climate.


EARTH-DIRECTED ERUPTION: A magnetic filament in the sun's northeastern quadrant erupted during the late hours of Nov. 30th. Click on the image to play a movie recorded by NASA's Solar Dynamics Observatory--and pay attention to the bright splash below the movie arrow:
The blast produced a B-class solar flare and hurled a bright coronal mass ejection (CME) into space. UPDATE: NOAA forecasters estimate a 30% chance of geomagnetic activity on Dec. 3rd when the CME is expected to deliver a glancing blow to Earth's magnetic field. High-latitude sky watchers should be alert for auroras.

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