coronal hole update

latimes.com

Sun’s bizarre behavior: Weakest solar cycle in 100 years

By Deborah Netburn

This post has been corrected. See note at the bottom for details.

7:00 AM PDT, July 12, 2013

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Those of us who have been paying attention to the sun this year have been a little … disappointed.

2013 was supposed to be the year of solar maximum — the peak of an 11-year cycle when the number of sunspots that mar the sun’s surface is at its highest.

These sunspots, which are actually cool areas on the sun’s surface caused by intense magnetic activity, are the sites of spectacular solar flares and CMEs, or coronal mass ejections, which can send billions of tons of solar material hurtling into space.

PHOTOS: Stunning views of the sun

But this year, the serious solar fireworks show never materialized.

Sure, we’ve seen a handful of major solar flares, and a few extra fast CMEs, but scientists say our current solar maximum, known as solar maximum 24, is the weakest one in 100 years.

And some scientists believe that the 25th solar maximum could be even weaker.

To help us understand what’s going on here, the American Astronomical Society asked three leading solar scientists to provide an update on the 24th solar maximum at a news conference Thursday.

It turns out there is some controversy in the scientific community about exactly why this year’s solar maximum has been so unspectacular.

One theory is that this year’s weak solar maximum is part of a 100-year solar cycle.

Graphs going back to the 1700s show that the number of sunspots during solar maximums in the early part of the last three centuries since humanity has been studying the solar cycle is much lower than the number of sunspots during solar maximums in the latter half of those centuries.

When asked what caused the 100-year cycles, the scientists admitted they did not know.

Other scientists are not convinced that this year’s weak solar maximum is part of a 100-year cycle, and have not ruled out the possibility that the sun might be on the verge of a Maunder Minimum, a period of time when it exhibits almost no sunspots. The last Maunder Minimum was observed in 1645. However, the last time there was a Maunder Minimum, it was preceded by a relatively strong solar maximum.

Nobody knows exactly what is going on, because we’ve only been studying the sun for such a tiny sliver of its life, and so much of its behavior is a mystery.

[For the Record, 10:43 a.m. PDT, July 12: An earlier version of this online post said the American Astrological Society had asked solar scientists to discuss the solar maximum. It was the American Astronomical Society.]

 

Aurora dances over Yellowstone

Posted: Jul 18, 2013 8:12 AM by Stephen Bowers

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This photo from Spaceweather.com tells the story: auroras lightened up the night sky over Yellowstone National Park earlier this week.

On Monday, Zack Clothier photographed these photos over the park and said the sky lit up with the auroral display at about midnight. He also points out the meteor streaking across the sky in his photo.

Last Saturday, July 13, a Coronal Mass Ejection (CME) swept by Earth. What is that? It is a bundle of solar energy hurled from the sun during a solar flare. Spaceweather.com says no geomagnetic storm occurred, but the solar wind poured into the Earth’s magnetosphere and the aurora danced in higher latitudes.

Another burst of solar wind is expected to sweep by Earth tonight (Thursday, July 18) and could bring about another colorful aurora.

This map from Spaceweather.com indicates an overall low probability for auroras over far northern Colorado. Over the higher latitudes of Canada, an aurora is more likely in areas of red and orange.

July 17, 2013 11:11 am

Coronal mass ejection heading toward Earth, may spark Northern Lights

By   Global News
 
 
 
 
 

On July 16, the sun unleashed a coronal mass ejection that is heading toward Earth.

On July 16, the sun unleashed a coronal mass ejection that is heading toward Earth.SDO

TORONTO – If the skies are clear the next few nights, Canadians might get a light show.

On July 16, the sun unleashed an Earth-directed coronal mass ejection (CME). A coronal mass ejection, a release of plasma and particles, can eject a billion tons of matter and travel at several million kilometres per hour. This CME should reach Earth on July 18.

When they reach Earth, the particles get trapped in our magnetic field, resulting in Northern Lights. Typically Northern Lights, or aurorae, are visible closer to Earth’s poles. As Canadians, we are in a prime viewing location.

An Earth-directed CME can cause a geomagnetic storm, which funnels energy into our planet’s magnetosphere for a few days. Aside from producing the Northern Lights, CMEs can also disrupt communication signals and cause electrical surges in power grids. In 1989, an Earth-directed CME caused a blackout in Quebec for several days.

 
 
 
 
 
 

 Aurorae dance in the skies near Lake Diefenbaker, about 100 kilometres south of Saskatoon. (Garry Stone)

Aurorae dance in the skies near Lake Diefenbaker, about 100 kilometres south of Saskatoon. (Garry Stone)

NASA said that typically, geomagnetic storms of this magnitude have been mild.

NASA has determined that this CME left the sun at 900 km/s. It may also pass by the MESSENGER spacecraft orbited Mercury as well as the Juno spacecraft that is on its way to Jupiter. NASA operators may put the spacecraft into safe-mode to protect their instruments.

Massive solar eruption to shoot past Earth

By    |   July 17, 2013   |   5

 

 

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The CME as captured by the European Space Agency and NASA Solar and Heliospheric Observatory.
(Credit: ESA&NASA/SOHO)

An enormous coronal mass ejection (CME) has sent particles into space that are due to pass the Earth in the next three days.

Although the solar maximum isn’t expected until late 2013, we’re starting to see some pretty spectacular effects: at 2.09pm AEST yesterday, the sun erupted in a massive coronal mass ejection that sent billions of tons of particles into the solar system in the direction of Earth.

It’s expected that this wave of particles will pass Earth within about three days, causing a phenomenon known as a geomagnetic storm. This is normal, and will cause no absolutely direct harm to humans.

The sun enters solar maximum every 11 years — the period of its cycle in which it is most active. This means we’ll see a rather marked increase in the number of CMEs and flares, with some pretty interesting effects here on Earth.

The coming geomagnetic storm will probably be relatively mild. The energy from the CME will buffet the Earth’s protective magnetosphere, which is likely to disrupt radio-based communications and navigation equipment, such as radio stations, walkie-talkies and satellite-based GPS.

Photographers and sightseers in the world’s northern and southern regions are in for a treat, though: geomagnetic storms also cause aurora borealis and australis, so keep your eyes on the skies. Space Academy has a guide on the best camera settings for snapping the phenomenon here.

Head over here if you want to see more of our crazy, magnificent sun.

Via www.nasa.gov

When space weather attacks!

By Brad Plumer, Updated: July 13, 2013

On a cool September night in 1859, campers out in Colorado were roused from sleep by a “light so bright that one could easily read common print,” as one newspaper described it. Some of them, confused, got up and began making breakfast.

Farther east, thousands of New Yorkers ran out onto their sidewalks to watch the sky glow, ribboned in yellow, white and crimson. Few people had ever seen an aurora that far south — and this one lit up the whole city.

At the time, it was a dazzling display of nature. Yet if the same thing happened today, it would be an utter catastrophe.

The auroras of 1859, known as the “Carrington Event,” came after the sun unleashed a large coronal mass ejection, a burst of charged plasma aimed directly at the Earth. When the particles hit our magnetosphere, they triggered an especially fierce geomagnetic storm that lit up the sky and frazzled communication wires around the world. Telegraphs in Philadelphia were spitting out “fantastical and unreadable messages,” one paper reported, with some systems unusable for hours.

Today, electric utilities and the insurance industry are grappling with a scary possibility. A solar storm on the scale of that in 1859 would wreak havoc on power grids, pipelines and satellites. In the worst case, it could leave 20 million to 40 million people in the Northeast without power — possibly for years — as utilities struggled to replace thousands of fried transformers stretching from Washington to Boston. Chaos and riots might ensue.

That’s not a lurid sci-fi fantasy. It’s a sober new assessment by Lloyd’s of London, the world’s oldest insurance market. The report notes that even a much smaller solar-induced geomagnetic storm in 1989 left 6 million people in Quebec without power for nine hours.

“We’re much more dependent on electricity now than we were in 1859,” explains Neil Smith, an emerging-risks researcher at Lloyd’s and co-author of the report. “The same event today could have a huge financial impact” — which the insurer pegs at up to $2.6 trillion for an especially severe storm. (To put that in context, Hurricane Sandy caused about $65 billion in damage.)

The possibility of apocalypse has piqued scientific interest in solar storms for many years. But researchers are now realizing that periodic space weather can cause all sorts of lesser mischief all the time, such as disorienting GPS satellites or severing contact between polar flights and air-traffic control.

So, in recent years, scores of businesses and government agencies have started to take space weather more seriously. Electric-grid operators are devising plans to reroute currents through their systems to brace for solar storms. Airlines such as Delta have developed plans to reroute flights in the case of emergency. The U.S. military has begun to realize that space-weather blips can disrupt communication in the heat of battle.

But preparing for disruptions isn’t easy. Just as interest in space weather is surging, the United States is facing the loss of key monitoring satellites in the coming years, as budget cuts mean that aging systems aren’t being replaced. And scientists are rushing to plug worrisome gaps in their knowledge about these storms.

The problem is far from theoretical. Last month, at a conference on space weather held by the National Oceanic and Atmospheric Administration, Daniel N. Baker of the University of Colorado told the audience that the sun had unleashed another large coronal mass ejection in July 2012 that traveled at speeds comparable to the Carrington Event of 1859. It missed the Earth by a week.

“Had that storm occurred a week earlier, it would have been a direct hit,” Baker said. “And we’d probably be having a very different conversation about this today.”

A year without power?

When it comes to space weather, the foremost concern is what a solar-induced geomagnetic storm might do to electric grids around the world.

At certain points in the sun’s cycle, as sunspots appear and flares erupt, the sun will eject part of its outer atmosphere, a cloud of fast-moving charged particles. If one of these coronal mass ejections hits the Earth’s magnetic field in just the right way, it can induce strong ground currents that travel through power lines, oil pipelines and telecom cables.

A truly severe geomagnetic storm could create currents powerful enough to overload electric grids and damage a significant number of high-voltage transformers, which can take a long time to repair or replace. That could leave millions without power for months or years.

“That’s a key vulnerability,” Smith says. “If you had a really big solar event, there just aren’t enough replacement transformers available. It can take up to 12 months to build new ones.”

As it turns out, most utilities don’t keep lots of spares around. The largest transformers, which convert the electricity in high-voltage lines to lower voltages, are custom-built, can cost millions of dollars and weigh up to 400 tons. Procuring a new one is a complex process that involves lining up the necessary copper and steel supplies, working with a long chain of manufacturers and arranging specialized transport. So, the Lloyd’s report notes, if even 20 transformers in the Northeast were knocked out, the logistical challenges would be “extremely concerning.”

Smith notes that the Northeast, with its aging power grid and peculiar geologic features, is especially at risk. Suffice it to say, it’s not fun to think about what would happen to the region if 40 million people had to go without power indefinitely.

Take Pittsburgh: One 2004 study by Carnegie Mellon University found that a large number of the city’s services were simply unprepared for an extended blackout. Half the city would lose water after three days if the city’s electrical pumps couldn’t be revived. Grocery stores, gas stations and cellphone networks would be knocked out. Police stations would go dark. Traffic lights would blink out. Most hospitals have backup systems in place, but emergency rooms would be strained if, say, the air conditioning went out during a hot summer.

“The absence of such fundamental services could lead to major and widespread social unrest, riots and theft,” the Lloyd’s report warns.

In theory, power utilities could try to take precautions if they had advance notice of a major solar storm headed our way. Using existing satellites, the National Weather Service’s Space Weather Prediction Center in Boulder, Colo., can detect an incoming event that’s about 30 minutes away.

Grid operators would have to react quickly. For example, PJM Interconnection operates a huge swath of the U.S. power grid from Illinois to the District, serving 60 million people. After receiving a  warning, human operators could re-dispatch electricity to reduce the flow of current from west to east. That would minimize the grid’s vulnerability to ground currents, Frank Koza, the executive director of operations support at PJM, said at the June space weather conference in Silver Spring.

For a modest solar storm, Koza said, PJM’s operators could respond if voltages started to drop anywhere in the system. (Pepco, which delivers electricity to 778,000 homes and businesses in the District and Maryland, is a member of PJM.)

But there’s a limit to how much these strategies can help. “The one we’re really concerned about is extreme space weather, a Carrington-level event,” Koza said. “What would happen in that scenario? I would have to tell you we don’t really know.”

For bigger storms, there are technologies that could harden the grid, such as capacitors that can help block the flow of ground currents induced by a geomagnetic event. In Quebec, the Canadian government has spent about $1.2 billion on these technologies since the 1989 blackout.

One problem, says Chris Beck of the Electric Infrastructure Security Council, is that many of these technologies are expensive and could make the current grid slightly less efficient in its day-to-day operations.

“We’ve designed our power lines to work efficiently under perfect conditions — long transmission lines, high voltages,” Beck says. Unfortunately, those characteristics make the grid particularly vulnerable to a solar storm. So there’s a trade-off.

Recently, the federal government decided to take a more serious look at the issue. Last fall, the Federal Energy Regulatory Commission issued an order that will eventually require grid operators to prepare both operational and technological responses to a space weather event.

Koza said he expects most grid operators to have response plans in the next year or two, but “engineered mitigation” could be another two to four years away.

Insurance companies, meanwhile, are trying to figure out how to get a handle on the risk from a solar storm. Will a major one come around once every 150 years? More often than that? “We’re hoping we might one day be able to cover these risks,” says Smith of Lloyd’s, “but we’ll need to be able to quantify them more accurately.”

Policymakers have also started getting involved. For a long time, conservatives such as Newt Gingrich were mostly interested in the risks to electric grids posed by a nuclear weapon that exploded in the atmosphere and induced ground currents. In June, Gingrich spoke to members of the Electromagnetic Pulse Caucus in the House, a group of 16 Republicans and two Democrats, about this possibility. “This could be the kind of catastrophe that ends civilization,” Gingrich said, “and that’s not an exaggeration.”

Now that the Cold War has ended, however, many of these Cassandras have switched over to warning about solar storms, which can have a similar effect, albeit on a smaller scale. Rep. Trent Franks (R-Ariz.), a founder of the EMP Caucus, has pushed a bill to protect against both “natural and man-made EMP events.” And in public, he tends to put more emphasis on solar storms.

“We’re starting to see more awareness there,” Beck says, “although we’re not quite to the point where we’re actually putting solutions in place.”

Unknown risks

Setting aside apocalyptic blackouts, solar storms and space weather can create all sorts of hiccups in the global economy that scientists are only beginning to understand.

Case in point: During the Battle of Takur Ghar in Afghanistan in 2002, a U.S. helicopter team was sent in to pick up a team of Navy SEALs. The SEALs sent a message to the helicopter warning the team not to land, but for some reason, it was never received. The helicopter landed under intense fire and four Americans were killed — an event dramatized in Sean Naylor’s bestselling account of Operation Anaconda, Not a Good Day to Die.

Some scientists now suspect that space weather could have been to blame for the incident.

At the space weather conference in June, Michael Kelly of the Johns Hopkins University Applied Physics Laboratory presented early evidence that a form of space weather known as “scintillation” can cause disturbances in the ionosphere and disrupt local radio communications. Researchers are working to model this phenomenon more accurately.

Airlines, too, have to take even lesser outbursts from the sun into account. Delta runs a number of commercial flights over the poles, such as routes between Detroit and Beijing and between Atlanta and Tokyo. But if they get a last-minute warning from the Space Weather Prediction Center of a geomagnetic storm, the planes often have to divert their routes away from the poles or risk losing radio contact with the ground. These diversions can cost thousands of dollars, Delta officials noted, so better predictions would help a great deal.

And those concerns only scratch the surface.

Joseph Kunches, a scientist at the Space Weather Prediction Center, says we’re still learning about activities that could be disrupted by solar weather. Satellite communications can go astray. Pipelines can corrode from ground currents. Even human space travel faces a threat.

“Radiation is a big issue for space travel — particularly once you get away from the Earth’s magnetic field,” he says. Astronauts working outside the Earth’s protective shield can be particularly vulnerable to bursts of solar radiation, which can have harmful health effects. That means that if we ever want to wander around in space, it would be helpful to have a better grasp of space weather.

“In 1972, there was actually a huge eruption that fortuitously fell between two of the Apollo flights, so the radiation didn’t hurt anybody,” Kunches says. “But it’s a problem.”

And there are still plenty of unknowns. Kunches and other experts pointed to the potential impact of solar eruptions on GPS technology. Certain storms could degrade the signal as it makes its way from the satellite to the ground. GPS is built into so much of the modern economy — from navigation to geophysical exploration by oil and gas companies — that any interference with GPS signals could be quite costly.

“I call it the cyber-electric cocoon we’ve built around the Earth,” says Baker, who heads the Laboratory for Atmospheric and Space Physics at the University of Colorado. “There are all these relationships that most people don’t even have a clue are there, and we’re still trying to understand everything that’s at risk.”

Satellite fleet may shrink

One big problem that businesses are having in preparing for a space weather attack is that they’re still not sure, exactly, what to prepare for. Minor impacts occur fairly often. But when might we expect a Carrington event? Or even something like the Quebec storm in 1989?

“Until we know that, the industry will be limited in its response,” said Koza of PJM Interconnection.

And there’s plenty more that space scientists are still trying to grasp. It’s difficult to predict, for instance, whether a solar outburst will actually create a storm when it hits Earth. A great deal depends on how a coronal mass ejection interacts with other solar winds as it moves toward us. Kunches likens it to knowing that a hurricane is coming, but not being able to measure its barometric pressure.

It would also be helpful to have more spacecraft studying the sun and giving us advance warning of storms. But, if anything, the Earth’s alert systems are about to get worse, not better.

Right now, NASA operates four space satellites situated between the Earth and the sun, which together can provide roughly 30 minutes’ warning of a major solar eruption. But these satellites are all reaching the end of their planned lives (and fuel tanks), and there’s only one replacement satellite scheduled to launch in 2014.

At the space conference in June, various speakers discussed ways to improve our ability to watch the sun. One engineer described fantastical plans for a satellite with a 100-square-meter“solar sail” that would use be steered and pushed by the sun’s photons in order to get closer and closer to the star without getting sucked in by gravity. A solar-sail satellite could, in theory, give us twice as much warning to prepare for a space storm.

But so far, these plans are all theoretical. “There’s a real need for a truly operational, 24-hour-a-day, seven-day-a-week space weather observatory,” Baker says. “But right now, we don’t see that coming from policymakers or the agencies that would have to step up.”

That means we may have to hope for a bit of luck in the years ahead. Solar activity tends to follow an 11-year cycle, with the most intense events often occurring near the peaks of the solar maximum — which, NASA says, could well arrive in late 2013 and again in 2015, although it’s difficult to predict for sure.

That doesn’t mean the big one will hit then. For one thing, sunspot activity has been rather muted of late, and the current maximum has been surprisingly weak. But for many experts, it’s a good reason to keep the sun in mind.

“We’re really on an unknown timeline here,” Beck says. “One of these could happen at any time.”

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