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rynner2 What a Cad!
Great Old One Joined: 13 Dec 2008 Total posts: 21369 Location: Under the moon Gender: Male |
 Posted: 07-03-2012 20:56 Post subject: |
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A recent Horizon:
Horizon - 2011-2012
- 9. Solar Storms - The Threat to Planet Earth
There is a new kind of weather to worry about, and it comes from our nearest star.
Scientists are expecting a fit of violent activity on the sun which will propel billions of tonnes of superheated gas and pulses of energy towards our planet. They have the power to close down our modern technological civilisation - e.g. in 1989, a solar storm cut off the power to the Canadian city of Quebec.
Horizon meets the space weathermen who are trying to predict what is coming our way, and organistions like the National Grid, who are preparing for the impending solar storms.
http://www.bbc.co.uk/iplayer/episode/b01d99vb/Horizon_20112012_Solar_Storms_The_Threat_to_Planet_Earth/
Broadcast on
BBC Two, 11:20PM Tue, 6 Mar 2012
Available until
10:59PM Tue, 17 Apr 2012 |
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| Mythopoeika Boring petty conservative
Joined: 18 Sep 2001 Total posts: 9109 Location: Not far from Bedford Gender: Unknown |
| Posted: 07-03-2012 21:11 Post subject: |
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| I saw that last night. The interesting thing was that the entire National Grid has to be turned on to ride out the storm. It's a bit counter-intuitive, because you'd think the best thing to do would be to turn it all off. |
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| ramonmercado Psycho Punk
Joined: 19 Aug 2003 Total posts: 17938 Location: Dublin Gender: Male |
| Posted: 09-03-2012 01:33 Post subject: |
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Is it safe to come out of the bunker? Vid & images at link.
| Quote: | Solar storm passes without incident so far
http://www.cpgb.org.uk/article.php?article_id=1004752
Nasa image showing extreme ultraviolet wavelengths on Sun's surface
Related Stories
Q&A: Solar storms
Space storm on the Sun's surface
Strong solar storm lashes Earth
A solar storm in the Earth's magnetic field has largely passed, but adverse effects could still occur, experts say.
"The freight train has gone by, and is still going by, and now we're just watching for how this is all going to shake out," said Joseph Kunches, a scientist with US weather agency Noaa.
Charged particles from the Sun will keep on passing the Earth until Friday.
There had been fears that this "coronal mass ejection" could wreak havoc with satellites or power grids on Earth.
However, up to this point, Dr Kunches said, "all told, it's not a terribly strong event".
The current coronal mass ejection (CME) - travelling at some 1,300km per second - began arriving at Earth on Thursday morning, after the release of two particularly strong solar flares earlier in the week.
'Wake-up call'
Activity near the Sun's surface rises and falls through an 11-year cycle that is due to peak in 2013 or 2014.
Some solar flares result in CMEs - the launch of a huge bubble of charged particles hurtling toward the Earth at speeds up to millions of kilometres per hour.
Continue reading the main story
Solar Storms
The sudden release of magnetic energy stored in the Sun's atmosphere can cause a bright flare
This can also release bursts of charged particles into space
These solar "eruptions" are known as coronal mass ejections or CMEs
When headed in our direction, the charged gas collides with the magnetic "sheath" around Earth
The subsequent disturbances in the Earth's magnetic envelope are called solar storms
They can interfere with technology: satellites, electrical grids and communications systems
They can also cause aurorae - Northern and Southern Lights - to be seen at lower latitudes
BBC Solar System: Solar Wind
BBC Solar System: The Sun
The Earth's magnetic field protects it from the constant onslaught of high-energy particles from the Sun and elsewhere in the cosmos.
However, the solar storms that mark the arrival of CMEs can disrupt the field enough to have an effect on the Earth's surface - causing current spikes in power grids or disrupting navigation devices.
Among the more benign effects is that the magnetic-field disturbance can make the Northern Lights visible at lower latitudes.
But it is often unclear, even up to the last minute, just how grave or spectacular the effects will be on Earth - that depends on the magnetic alignment of the material within the CME, which is difficult to predict.
Because different parts of the bubble can have different alignments, scientists say that the storm could still have adverse effects as it passes.
"The magnetic field in the solar wind is not facing in the direction of danger. But it could change, into the early evening," said David Kerridge, director of geoscience research at the British Geological Survey.
Although space weather scientists have seen no more significant activity since the solar flares that launched the current storm, scientists around the globe are still keeping an a close watch on the Sun.
"The part of the Sun where this came from is still active," Dr Kerridge told BBC News. "It's a 27-day cycle and we're right in the middle of it, so it is coming straight at us and will be for a few days yet. We could see more material," he explained.
But regardless of its eventual extent, this episode of solar activity is a preview of what is to come in the broader, 11-year solar cycle.
Dr Craig Underwood, from the Surrey Space Centre, UK, said: "The event is the largest for several years, but it is not in the most severe class. We may expect more storms of this kind and perhaps much more severe ones in the next year or so as we approach solar maximum.
"Such events act as a wake-up call as to how our modern western lifestyles are utterly dependent on space technology and national power grid infrastructure."
Many storms are benign; this storm could enable skywatchers to see the Northern Lights from parts of the northern US and northern UK.
But the strongest storms can have other, more significant effects.
In 1972, a geomagnetic storm provoked by a solar flare knocked out long-distance telephone communication across the US state of Illinois.
And in 1989, another disturbance plunged six million people into darkness across the Canadian province of Quebec. |
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| ramonmercado Psycho Punk
Joined: 19 Aug 2003 Total posts: 17938 Location: Dublin Gender: Male |
| Posted: 31-07-2012 01:23 Post subject: |
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Head for the bunkers again.
| Quote: | Solar Storm Expected to Hit Earth Tuesday
http://www.space.com/16818-solar-flare-geomagnetic-storm-forecast.html
by SPACE.com StaffDate: 30 July 2012 Time: 03:32 PM ET
An M6-class solar flare erupted from the sun on July 28, 2012.
CREDIT: NASA
View full size image
A medium-size solar flare erupted from the sun this weekend, hurling a cloud of plasma and charged particles toward Earth on a cosmic path that is expected to deliver a glancing blow to our planet tomorrow (July 31), according to space weather forecasters.
The M6-class solar flare exploded from the sun on Saturday (July 2 , unleashing a wave of plasma and charged particles, called a coronal mass ejection (CME), into space. The CME is expected to reach Earth tomorrow, and could deliver a glancing blow to Earth's magnetic field at around 11 a.m. EDT (1500 GMT), according to the website Spaceweather.com, which regularly monitors space weather events.
"This is a slow-moving CME," astronomer Tony Phillips wrote on Spaceweather.com. "The cloud's low speed (382 km/s estimated) combined with its glancing trajectory suggests a weak impact is in the offing. Nevertheless, polar geomagnetic storms are possible when the cloud arrives."
Powerful, fast-moving CMEs that hit Earth directly can trigger strong geomagnetic storms that cause radio blackouts and disrupt power grids and other communications infrastructure. These clouds of charged particles can also knock out satellites as they travel through space.
A more benign effect of solar storms, however, is supercharged northern and southern lights, which can be sparked when the CME's charged particles hit Earth's magnetic field. Solar storm forecasts are often accompanied by alerts for auroras at high- and mid-latitudes, though particularly strong geomagnetic storms can generate auroras at lower-than-normal latitudes.
Saturday's M6-class solar flare erupted from the active sunspot AR1532, which is slowly rotating across the solar disk. X-class solar flares are the strongest type of solar eruptions, with M-class flares ranking as medium-strength, and C-class flares representing the weakest type. [Video: Strong Sun Flare Erupts Towards Earth]
While Earth may be safe from being hit head-on by the CME, Mercury, the planet closest to the sun, will not be as lucky.
"The CME will also hit Mercury, probably with greater force," Phillips wrote on Spaceweather.com. "Mercury's planetary magnetic field is only ~10 percent as strong as Earth's, so Mercury is not well protected from CMEs. When the clouds hit, they can actually scour atoms off Mercury's surface, adding material to Mercury's super-thin atmosphere and comet-like tail."
The sun's activity waxes and wanes on a roughly 11-year cycle. The sun's current cycle, called Solar Cycle 24, began in 2008. The sun's activity is expected to ramp up toward a solar maximum in 2013.
Editor's note: If you snap aurora or sunspot photos that you'd like to be considered for use in a story or gallery, please send them to SPACE.com managing editor Tariq Malik at tmalik@space.com. |
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| rynner2 What a Cad!
Great Old One Joined: 13 Dec 2008 Total posts: 21369 Location: Under the moon Gender: Male |
| Posted: 24-06-2013 20:36 Post subject: |
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Documentary about solar activity:
The Secret Life of the Sun
90 million miles away from us is the power that shapes our world - the Sun. We see it shine in the sky above us, but beyond our sight something dramatic is happening - the Sun is going into overdrive.
It's more active now that it's been for a decade, sending eruptions of super-heated plasma and vast waves of radiation towards our planet. With the potential to disrupt our lives in dramatic ways.
Using the latest satellite images, and the expertise of Britain's leading solar scientists, Kate Humble and Helen Czerski reveal the inner workings of our very own star, and the influence its mysterious cycles of activity have on our planet.
They discover why the light reaching us from the Sun can be up to a million years old: they meet the teams who protect us by keeping a round-the-clock vigil on the Sun; and investigate why some scientists think longer term changes in the Sun's behaviour may have powerful effects on our climate.
http://www.bbc.co.uk/iplayer/episode/b03694kd/The_Secret_Life_of_the_Sun/
Available until
12:19AM Wed, 3 Jul 2013 |
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