Is our Sun falling silent? Prof. Richard Harison

[PkRevolution]

BBC News 17.01.2014

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"I've been a solar physicist for 30 years, and I've never seen anything quite like this," says Richard Harrison, head of space physics at the Rutherford Appleton Laboratory in Oxfordshire.

He shows me recent footage captured by spacecraft that have their sights trained on our star. The Sun is revealed in exquisite detail, but its face is strangely featureless."If you want to go back to see when the Sun was this inactive... you've got to go back about 100 years," he says.This solar lull is baffling scientists, because right now the Sun should be awash with activity.

The Sun's activity may be falling faster than at any time in 10,000 years
It has reached its solar maximum, the point in its 11-year cycle where activity is at a peak.This giant ball of plasma should be peppered with sunspots, exploding with flares and spewing out huge clouds of charged particles into space in the form of coronal mass ejections.

But apart from the odd event, like some recent solar flares, it has been very quiet. And this damp squib of a maximum follows a solar minimum - the period when the Sun's activity troughs - that was longer and lower than scientists expected."It's completely taken me and many other solar scientists by surprise," says Dr Lucie Green, from University College London's Mullard Space Science Laboratory.The drop off in activity is happening surprisingly quickly, and scientists are now watching closely to see if it will continue to plummet."It could mean a very, very inactive star, it would feel like the Sun is asleep... a very dormant ball of gas at the centre of our Solar System,"
explains Dr Green.

This, though, would certainly not be the first time this has happened.During the latter half of the 17th Century, the Sun went through an extremely quiet phase - a period called the Maunder Minimum.Historical records reveal that sunspots virtually disappeared during this time.Dr Green says: "There is a very strong hint that the Sun is acting in the same way now as it did in the run-up to the Maunder Minimum."Mike Lockwood, professor of space environment physics, from the University of Reading, thinks there is a significant chance that the Sun could become increasingly quiet.An analysis of ice-cores, which hold a long-term record of solar activity, suggests the decline in activity is the fastest that has been seen in 10,000 years."It's an unusually rapid decline," explains Prof Lockwood.

Read More:

http://www.bbc.co.uk/news/science-environment-25743806

 

[jason]

Earth Needs Better Preparation For Massive Solar Storm, Scientist Says

The Huffington Post | By Matt Ferner Posted: 12/11/2013 3:13 pm EST | Updated: 01/16/2014 3:47 am EST

Policy makers in the U.S. need to get serious about the threat posed by solar storms. So says Dr. Daniel Baker, a University of Colorado solar scientist with significant expertise in sun storms -- like the huge one the sun fired off in July 2012.
My space weather colleagues believe that until we have an event that slams Earth and causes complete mayhem, policy makers are not going to pay attention, Baker, director of the university's Laboratory for Atmospheric and Space Physics, said in a written statement. The message we are trying to convey is that we made direct measurements of the 2012 event and saw the full consequences without going through a direct hit on our planet.
The high-energy particles liberated by a major flare could disrupt transportation, communication, and financial systems in addition to limiting the availability of food, medications, and drinking water, according to a 2008 National Resource Council report, which Baker co-authored.
Baker isn't alone in his concern over the risk posed by solar storms. A 2013 report from the Royal Academy of Engineering in London called for the creation of a space weather board to help plan for a solar superstorm. It also called for a system to warn of dangerous space weather radiation.
What exactly is Baker proposing? That the 2012 event be adopted as "the best estimate of the worst case space weather scenario" and be used to create models to predict the effects such a storm would have on power grids and other vulnerable systems.
The 2012 solar storm largely missed Earth but could have been highly disruptive if radiation from it had given the planet a direct hit, Baker said. The area of the sun that produced the solar explosion was facing away from us, but just a week earlier that same area was pointed right at Earth, he said.
The 2012 event was also alarming to Baker for the speed at which the radiation it produced traveled through space. Generally, coronal mass ejections take two to three days to reach Earth, but the 2012 ejection reached Earth in 18 hours.
The speed of this event was as fast or faster than anything that has been seen in the modern space age, Baker said in the statement. "The event not only had the most powerful CME ever recorded, but it would have triggered one of the strongest geomagnetic storms and the highest density of particle fluctuation ever seen in a typical solar cycle, which lasts roughly 11 years."
The largest solar storm on record is believed to be the so-called "Carrington event" in 1859 -- an event that reportedly set telegraph machines ablaze and caused auroras borealis so bright that people could read well into the night. Yet there's speculation that the 2012 CME was likely even more powerful.
The Carrington storm and the 2012 event show that extreme space weather events can happen even during a modest solar cycle like the one presently underway, Baker said. Rather than wait and pick up the pieces, we ought to take lessons from these events to prepare ourselves for inevitable future solar storms.