Solar Storms Building Toward Peak in 2013, NASA Predicts

by Clara Moskowitz, SPACE.com Assistant Managing Editor
Date: 09 August 2011 Time: 05:06 PM ET

This image from the Solar Dynamics Observatory shows the X6.9 solar flare of Aug. 9, 2011 near the western limb (right edge) of the sun. CREDIT: NASA/SDO/Weather.com

Solar flares like the huge one that erupted on the sun early today (Aug. 9) will only become more common as our sun nears its maximum level of activity in 2013, scientists say.

Tuesday’s flare was the most powerful sun storm since 2006, and was rated an X6.9 on the three-class scale for solar storms (X-Class is strongest, with M-Class in the middle and C-Class being the weakest).

Flares such as this one could become the norm soon, though, as our sun’s 11-year cycle of magnetic activity ramps up, scientists explained. The sun is just coming out of a lull, and scientists expect the next peak of activity in 2013. The current cycle, called Solar Cycle 24, began in 2008.

“We still are on the upswing with this recent burst of activity,” said Phil Chamberlin, a solar scientist at NASA’s Goddard Space Flight Center in Greenbelt, Md., who is a deputy project scientist for the agency’s Solar Dynamics Observatory, a sun-studying satellite that launched in February 2010. “We could definitely in the next year or two see more events like this; there’s a potential to see larger events as well.”

A more active sun

Earth got lucky with the most recent flare, which wasn’t pointed directly at Earth; therefore, it didn’t send the brunt of its charged particles toward us, but out into space. However, we may not be so fortunate in the future, experts warned.

“We’re in the new cycle, it is building and we’ll see events like this one,” said Joe Kunches, a space scientist with the National Oceanic and Atmospheric Administration (NOAA)’s Space Weather Prediction Center. “They’ll be much more commonplace and we’ll get more used to them.”

Spacecraft such as the Solar Dynamics Observatory (SDO), which recorded amazing videos of the Aug. 9 solar flare, and other observatories will be vital in monitoring the sun during its active phase, researchers said.

How sun storms form

Storms brew on the sun when pent-up energy from tangled magnetic field lines is released in the form of light, heat and charged particles. This can create a brightening on the sun called a flare, and is also often accompanied by the release of a cloud of plasma called a coronal mass ejection (CME).

These ejections are the part we Earthlings have to worry about.

As the CME careens through space, it can send a horde of charged particles toward our planet that can damage satellites, endanger astronauts in orbit, and interfere with power systems, communications and other infrastructure on the ground.

“We’re well aware of the difficulties and challenges,” Kunches told SPACE.com. “We know more about the sun than we ever have.”

Can we predict solar storms?

When a big storm occurs, the Space Weather Prediction Center releases a warning to the U.S. Department of Homeland Security, emergency managers and agencies responsible for protecting power grids. Then power grids can distribute power and reduce their loads to protect themselves.

Satellite and power companies are also trying to design technology that can better withstand the higher radiation loads unleashed by solar storms.

Still, scientists would like to offer more advanced warnings when big storms are headed our way.

“We’re being reactive, we’re not being proactive,” Chamberlin said. “We don’t know how to predict these things, which would be nice.”

Chamberlin said solar science has come a long way in recent years, though, and the goal of SDO and other NASA projects is to improve our understanding of the sun and our ability to forecast space weather.

You can follow SPACE.com senior writer Clara Moskowitz on Twitter @ClaraMoskowitz. Follow SPACE.com for the latest in space science and exploration news on Twitter @Spacedotcom and on Facebook.

Solar Storms Building Toward Peak in 2013, NASA Predicts | Solar Flares & Storms | Space & Solar Weather | Space.com.

Huge Sunquakes Triggered by Solar Eruptions

Massive solar wind bursts and magnetic fields can cause ripples on sun’s surface

By Kat Piper
Epoch Times Staff
Created: March 30, 2012
Last Updated: April 4, 2012

Massive bursts of solar wind and magnetic fields from the Sun can cause huge sunquakes, according to new UK research.

The results of the study, led by University College London’s Mullard Space Science Laboratory, are being presented by Dr Sergei Zharkovat at the National Astronomy Meeting 2012 in Manchester on Friday, March 30.

Research over the last 10 years has shown that sunquakes can be produced when solar flares—huge explosions of energy in the Sun’s atmosphere—impact and travel into the Sun. The quakes appear as circular ripples on the surface of the Sun.

The new study shows that eruptions of charged particles and magnetic fields known as Coronal Mass Ejections (CMEs) are also able to produce sunquakes.

“Sunquakes are generated by solar flares, when enormous amounts of energy are released high up in the solar atmosphere. Most of the energy goes up into interplanetary space, but a fraction of this energy travels to the Sun’s surface creating a sonic boom that causes the solar interior to oscillate and produce the ripples,” explained Zharkov in an email.

“I sometimes think of sunquakes as thunder to the flare’s lightning, except imagine a lightning over an ocean that is so strong that it creates a tsunami.”

The researchers studied an eruption that took place on Feb. 15, 2011. They found that sunquakes 1,000 times more powerful than the March 2011 Japanese earthquake were triggered at two ends of the erupting rope of magnetic field. The sudden expansion of the magnetic field as it erupts is thought to play a part in the generation of the sunquakes.

The eruption travelled through our solar system at around 600 kilometres per second (1.34 million miles per hour) towards Earth, causing a geomagnetic storm and aurora when it hit the Earth’s atmosphere.

It is for this reason that study of sunquakes is of interest, especially as solar activity is predicted to increase and peak in 2013.

“Sunquakes themselves do not have [an] impact on Earth as they are acoustic waves travelling inside the Sun. But flares and, accompanying them, Coronal Mass Ejections that we have shown play an important role in generating sunquakes, can and do impact Earth,” Zharkov said.

“Sunquakes now form an integral part for our search for understanding of flare and CME phenomena.”

Flares and CMEs have a direct impact on space weather, so understanding how they form could help in predicting when they are going to occur and planning for possible geomagnetic storms, which can affect satellites and radio and GPS equipment on Earth.

But sunquakes are relatively rare, explained Zharkhov. “Known sunquakes were all generated by string solar flares (X and M class), which occur only during the active part of an [11-year] Solar Cycle. However, only a small fraction of such flares produce sunquakes,” he said.

“There is also a chance, however, that sunquakes are more common than we think; it’s just that our means of detecting them are not yet up to scratch.”

Until recently, observation of sunquakes had been hampered by availability of data. “With the (relatively) new NASA’s Solar Dynamics Observatory satellite providing us with practically continuous high resolution and high cadence observations of the Sun, this problem is now solved,” Zharkov said.

Much like geologists use earthquakes to understand the internal structure of our planet, future research will be focused on using sunquakes to learn more about the internal processes of the Sun, said Zharkov. As scientists still don’t fully understand how sunquakes are generated, research will also continue to look for physical explanations of this solar phenomenon.

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Huge Sunquakes Triggered by Solar Eruptions | Space & Astronomy | Science | Epoch Times.

Magnetic mysteries of Earth’s Core

30 August 2011 | Last updated at 20:45 ET
By Gaby Hornsby, BBC Horizon

The magnetic field emanating from Earth’s core helps create the Northern Lights

Earthquakes, explosions and observations of Earth’s ever-changing magnetic field are helping scientists open up a new window on the heart of our planet.

When Jules Verne wrote A Journey to the Centre of the Earth over 100 years ago, he imagined a place of glowing crystals and a turbulent sea, complete with prehistoric animals and giant mushrooms.

What was actually beneath our feet was a complete enigma. Even to this day scientists astonishingly know more about the rings of Saturn than they do about the core of our own planet.

But that is beginning to change. “We’re at a golden age in terms of the real discovery of the bulk of the deep Earth,” says seismologist Professor Rick Aster.

And remarkably, not everything Verne imagined was wrong.

Wanting to discover the truth about the centre of our world is as basic a human urge as wondering what is on the Moon, although the latter has proved far easier to explore.

But scientists are also fascinated by the Earth’s core because it is responsible for creating our planet’s magnetic field which is vital to life.

As a tool for navigation, it helps honey bees find their hive, while sea turtles, birds and butterflies use it to migrate over long distances.

The magnetic field also acts as a protective barrier between us and some of the dangers of space, shielding us from radiation in the solar wind.

Physically travelling to the core has proved a non-starter though, because of the rapidly increasing pressures and temperatures.

Even with remote drilling, the deepest we have managed to penetrate is 12km at the Kola Superdeep Borehole in Russia – a measly 0.2% of the way to the centre of the Earth.

Molten metal

But seismology has allowed scientists to sense right into the core of the planet. The seismic waves generated during major earthquakes travel from one side of the Earth to the other, allowing scientists to build up a picture of the interior.

Seismology is “the killer application”, says Aster, showing us the Earth has a molten outer-core, “an enormous ocean of white hot molten metal that’s almost as runny as water”.

This core is as large as Mars. But – like a planetary Russian doll – another core was found within this one. An inner-core – a solid metal ball almost the size of the Moon.

Scientists believe the solid inner core is made of an iron-nickel alloy.

To understand what form it might take under the extreme conditions at the centre of the Earth, Professor Kei Hirose set himself a seemingly impossible challenge: recreate the conditions of the core in his lab at the SPring-8 synchrotron near Osaka, Japan. After 10 years of trying, he has finally succeeded.

Crystal forest


Extreme conditions found at the Earth’s core have been recreated in the laboratory

He has created an incredibly powerful vice using the tips of two diamonds. Between them he has pressurised a sample of iron-nickel to three million times atmospheric pressure and heated the sample to about 4,500C.

Under these extraordinary conditions, the crystal structure of iron-nickel alloy changed and the crystals rapidly grew in size. “We may have very big crystals at the centre of the Earth, maybe up to 10km,” says Hirose.

These crystals would all align “like a forest”, says Hirose, pointing at the poles.

The bulk of the Earth’s magnetic field is generated not in the inner-core but in the molten metal of the outer-core. This acts as a massive electromagnetic dynamo powered by the Earth’s rotation and the long-term cooling of the planet.

But although the basic principle is understood, the details of how the molten metal moves are a mystery. As Earth rotates and loses heat from the centre, complex patterns of flow are created within this vast ocean.

“You might think of the core like the atmosphere of the Earth, being a very restless place with storms and fronts and bad weather,” says geophysicist Professor Dan Lathrop from the University of Maryland. He has built himself a massive model of the core to help explain something strange about the field – it is never fixed but constantly fluctuating.

The Earth’s magnetic field has been steadily weakening over the past 180 years. And there is one patch that is weakening faster than any other. It is an area scientists have dubbed the “South Atlantic Anomaly”, which sits over the South Atlantic and the centre of South America.

It is a known hazard for spacecraft because it creates a dip in the field, allowing charged particles into the orbit of satellites and upsetting their electronics and instrumentation.

Magnetic flip

But what some scientists suspect is that it could be much more than an inconvenience to satellite operators – it could be the first indication of a profound change in Earth’s magnetic field.

When scientists mapped the Earth’s magnetic field down to the level of the outer-core, they discovered that under the South Atlantic Anomaly the simple north-south divide we know at the surface had broken down. There are patches where the field has actually flipped and points north instead of south.

Using his weather analogy, Lathrop believes “a particularly violent or unusual patch of weather” in the molten metal of the outer-core is responsible for reversing the field.

If these patches continue to deepen and spread, the entire Earth’s magnetic field could reach a tipping point and flip, he believes.

It is not something that would happen overnight – it could take thousands of years, during which period the field would be pretty confused.

The magnetic poles could wander to the equator for example, and take with them the spectacular Northern Lights. It would not be out of character – the shifting flows of the core have reversed Earth’s field hundreds of times before.

“It’s not a question of if the Earth is going to reverse the magnetic field, but when,” says Lathrop.

Exactly when this might be remains one of the core’s many mysteries. But after centuries of speculation, scientists are finally beginning to understand this great wonder lying 6,000km beneath our feet.

via BBC News – Magnetic mysteries of Earth’s Core.