Category Archives: solar storms

Epic Geomagnetic Storm Erupts

Epic Geomagnetic Storm Erupts : Discovery News.

Right this moment, there’s an epic magnetic battle raging above our heads.

On Monday, at around 2 p.m. ET, a coronal mass ejection (CME) slammed into the Earth’s magnetosphere. According to NASA’s Space Weather Laboratory, the conditions were just right for the CME’s magnetic field to compress the Earth’s magnetosphere so much that, for a short time (between 3:06 p.m and 3:11 p.m. ET), energetic solar wind particles penetrated as deep as geosynchronous orbit — home to hundreds of communication satellites.

ANALYSIS: Epic Aurora Caught Cross Country — Share YOUR photos of the aurora!

Although the interactions between solar plasma and Earth’s magnetic field are often invisible, tonight is an exception. Vast aurorae are rippling through the atmosphere at very low latitudes.

At time of writing, the US was being given a dazzling show as Spaceweather.com reports:

Northern Lights have spilled across the Canadian border into the contiguous USA. Sighting reports have come from as far south as Arkansas, Wisconsin, Michigan, Tennessee, Missouri, Illinois, Nebraska, Kentucky, Indiana, Oklahoma, Kansas, Maryland, New York, Ohio and central California.

Yes, central California! To see some of the auroral displays, the Universe Today has a few reader’s photos featured. My personal favorite is an earlier photograph taken in Norway.

SCIENCE CHANNEL: VIDEO: Jupiter’s Storms

Why is this happening? And why now?

It is well known that the sun is building in activity toward “solar maximum” — the peak is predicted to occur by around 2013 — and we have witnessed some huge solar flares recently.

Flaring activity and the eruption of CMEs are both symptomatic of the extreme magnetic stresses torturing the sun’s interior.

So, we’ve just experienced a CME punch — solar plasma contained within the CME and solar wind have streamed into the magnetosphere. Usually these energetic particles would follow the magnetic field lines and be confined to the North and South Polar Regions, creating the familiar Aurora Borealis and Aurora Australis, respectively — as the solar particles rain down through the atmosphere, impacts with atmospheric gases cause the atmosphere to glow. But this time the conditions were just right that the powerful CME impact caused a geomagnetic storm to ripple across the globe, extending the aurorae.

ANALYSIS: How Does the Sun Affect the Earth?

Scientists are able to measure when a geomagnetic storm is underway by using the “Kp index.” This measurement is derived by measuring how much the horizontal component of the Earth’s magnetic field varies over a 3-hour period. Depending on the intensity of fluctuations, the Kp index is assigned values between 0 to 9. If the value hits 5, this means a geomagnetic storm is occurring and auroral displays can be expected.

At its peak, the Kp index hit a “7” — a strong geomagnetic storm!

Kp

Apart from generating beautiful auroral displays at lower latitudes than would be expected, strong geomagnetic storms can have a sinister side. As energetic particles wash through our orbital neighborhood, vulnerable satellites can be damaged and huge electrical currents can be induced through the upper atmosphere, potentially overloading entire power grids.Watch movie online The Transporter Refueled (2015)

SLIDE SHOW: Extreme Space Weather

Last year, the much-publicized “zombiesat” was caused by a solar storm knocking out a satellite’s ability to communicate with Earth. Its brains were, quite literally, “fried.”

And if you think it’s not possible for the sun to damage a power grid, think again. In 1989, Hydro-Québec power grid was knocked out by a geomagnetic storm caused by a CME hitting the Earth. Just before the grid was knocked out — leaving millions of customers without power for several hours — aurorae were spotted as far south as Texas.

It is unlikely that the current geomagnetic storm will cause satellite harm or power grid mayhem, but as society becomes ever more dependent on delicate electronics and constant mains electricity, we become increasingly vulnerable to the awesome violence of solar eruptions.

Space Weather Forecasters Get Closer to worthwhile predictions

Space Weather Forecasters Get Serious – ScienceNOW.

 

A new forecast model simulates the approach of a coronal mass ejection (boomerang of color) to Earth (green dot) that would trigger a solar storm.

It took a while, but space physicists who predict immense balls of solar debris smashing into Earth have finally caught up with their brethren who forecast terrestrial weather. Rather than simply relying on rules of thumb, space weather forecasters have begun running a computer model that actually simulates the development of conditions between the sun and Earth. They’re following the lead of atmospheric weather forecasters, who have been using computer models since the 1960s. Warnings of when solar storms will strike Earth are already much improved.

The better the warning of major solar storms, the better earthlings can prepare for the consequences, which can include electrically fried satellites, degraded GPS navigation, and widespread blackouts. The culprit is a magnetic bubble of tens of millions of tons of protons and the like blown off the sun at several million kilometers per hour. It might seem easy enough to keep track of something that big, but observation platforms between the sun and Earth are few and far between. And the choppy sea of magnetic fields and charged particles that the ejected bubbles plow through can slow and deflect the bubbles.

Drawing on the typical behavior of previous bubbles, called coronal mass ejections (CMEs), forecasters at the National Oceanic and Atmospheric Administration’s Space Weather Prediction Center (SWPC) in Boulder, Colorado, had been predicting the arrival of CMEs at Earth with an accuracy of plus or minus 15 hours. They would usually say which day a storm might strike but not much more.

The new forecasting system, developed by a consortium of 11 institutions led by Boston University and refined by SWPC, has been in routine operation since the beginning of the month. It includes a computer simulation that calculates how a particular CME will move out from the sun and through the evolving interplanetary “weather” on its way to Earth. One model component handles a particular CME moving from the sun’s surface into interplanetary space, and another simulates its progress in three dimensions out to Earth’s orbit and beyond.

The new model components allowed SWPC forecasters to shrink their timing error from 15 hours to 6 hours. “From a space weather standpoint, that’s a pretty big deal,” says space physicist Daniel Baker of the University of Colorado, Boulder. “The forecast model gives some confidence in predictions” for the vicinity of Earth.

Not that forecasts couldn’t use a lot more improvement. For instance, there’s no sign as yet that the advent of physics-based forecasting will improve predictions of the power of a solar storm inside Earth’s magnetic cocoon where it matters, notes forecaster Douglas Biesecker of SWPC. To anticipate that, researchers will have to understand much more about the innards of CMEs.

 

Huge Sun Storm Should Super-Charge Northern Lights

Huge Sun Storm Should Super-Charge Northern Lights Tonight | Solar Storms & Northern Lights | The Sun & Space Weather | Space.com.

Sunspot 1302 has already produced two X-class flares.
Sunspot 1302 has already produced two X-flares (X1.4 on Sept. 22nd and X1.9 on Sept. 24th). Each of the dark cores in this image from SDO is larger than Earth, and the entire active region stretches more than 100,000 km from end to end. The sunspot’s magnetic field is currently crackling with sub-X-class flares that could grow into larger eruptions as the sunspot continues to turn toward Earth.
CREDIT: NASA/SDO/HMI

Particles that were blasted from the sun by a huge eruption over the weekend have reached Earth, causing geomagnetic storms on our planet, which will likely trigger a stunning northern lights show for some lucky skywatchers.

The particles reached at Earth at 8:37 a.m. EDT (1237 GMT) today (Sept. 26), kicking off moderate geomagnetic storms at lower latitudes and more serious storms closer to the Earth’s poles, according to the U.S. National Oceanic and Atmospheric Administration (NOAA). These storms can disrupt GPS signals, radio communications and power grids, but no such effects have yet been reported, NOAA officials said.

The storms should also give skywatchers in select locations a treat, creating dazzling auroras (phenomena also known as the northern and southern lights). [Photos: Auroras Dazzle Northern Observers]

 

“Aurora watchers in Asia and Europe are most favorably positioned for this event, though it may persist long enough for viewers in North America,” officials with NOAA’s Space Weather Prediction Center (SWPC) wrote in an update today.

A powerful solar eruption

The sun unleashed a powerful solar flare and an event known as a coronal mas ejection (CME) on Saturday (Sept. 24). CMEs are massive clouds of solar plasma that can streak through space at 3 million miles per hour (5 million kilometers per hour) or more.

Luckily, this CME delivered a glancing blow. If it had hit Earth directly, the geomagnetic storms — and, possibly, the damage — could have been more serious. But we’re not out of the woods yet, SWPC officials said.

 

The storm erupted from a region known as sunspot 1302. Sunspots are temporary dark patches on the solar surface caused by intense magnetic activity. The area around sunspot 1302 may be brewing up more trouble. [Photos: Sunspots on Earth’s Closest Star]

“Region 1302 remains capable of producing more activity and will be in a favorable position for that activity to have impacts on Earth for the next 3-5 days,” SWPC officials said.

For now, however, the biggest effect of the geomagnetic storms may be the auroras, so skywatchers in favorable locations should look up when they get the chance.

People in the mid- to high-latitudes should be alert for auroras after nightfall. The best hours to spot the northern and southern lights tend to be around local midnight, according to the website Spaceweather.com.

Sun ramping up

Sunspot 1302 has been particularly active lately, spouting off multiple X-class fares — the most poweful type — over the last few days. And that restlessness is part of a larger pattern, experts say.

Sunspot 1302 poses a continued threat for X-class solar flares.
Sunspot 1302 poses a continued threat for X-class solar flares.
CREDIT: SDO/HMI

Solar activity has been ramping up over the last few months as the sun has roused itself from an extended quiescent phase in its 11-year cycle of activity.

Just last month, for example, the sun let loose with an X6.9 solar flare, which was the most powerful solar storm since December 2006, NASA scientists said.

And the storms should keep coming over the next few years. Scientists expect activity in the current cycle — known as Solar Cycle 24 — to peak around 2013.

'Old Faithful' Sunspot to Fire Off More Flares

‘Old Faithful’ Sunspot to Fire Off More Flares, Scientists Say | Solar Flares & Coronal Mass Ejections | The Sun & Space Weather | Space.com.

Sunspot 1283 Storms
A giant plume of ionized gas called plasma (to the right) leaps off the sun from sunspot 1283 in this photo snapped by NASA’s Solar Dynamics Observatory. This sunspot spouted four solar flares and three coronal mass ejections from Sept. 6-8, 2011.
CREDIT: NASA/SDO/AIA

An active region of the sun that blasted out powerful solar storms four days in a row last week likely isn’t done yet, scientists say.

Officially, the flare-spouting region is called sunspot 1283. But space weather experts have dubbed it “Old Faithful,” after the famous geyser in the United States’ Yellowstone National Park that goes off like clockwork. And the solar Old Faithful should erupt again before it dissipates, researchers said.

“It still has a fair amount of complexity,” said solar physicist C. Alex Young of NASA’s Goddard Space Flight Center in Greenbelt, Md. “So we still have a pretty good chance of seeing some more stuff from this one.” [Photos: Sunspots on Earth’s Closest Star]

 

An active sunspot

Sunspots are temporary dark patches on the solar surface caused by intense magnetic activity. Some last for hours before disappearing; others linger for days, weeks or even months.

Powerful solar storms often erupt from sunspots. These include radiation-flinging solar flares and phenomena known as coronal mass ejections (CMEs) — massive clouds of solar plasma that can streak through space at up to 3 million mph (5 million kph).

From Sept. 5-8, sunspot 1283 produced four big flares and three CMEs. Two of the flares were X-class events and two were M-class flares. (Strong solar flares are classified according to a three-tiered system: X-class are the most powerful, M-class are of medium strength and C-class are the weakest.)

While the rapid motion previously observed in sunspot 1283 seems to have died down a bit, Young said, the sunspot looks poised to erupt again sometime soon.

“There’s a good probability that we’re still going to see at least another M-class flare, possibly another X-class flare,” Young told SPACE.com.

It’s not uncommon for sunspots to pop off a number of powerful flares in quick succession the way 1283 has done, he added. That seems to be the natural order of things.

“When you see one big flare, your chances of seeing another one are pretty good,” Young said.

A photo of a sunspot taken in May 2010, with Earth shown to scale. The image has been colorized for  aesthetic reasons. This image with 0.1 arcsecond resolution from the Swedish 1-m Solar  Telescope represents the limit of what is currently possible in te
A photo of a sunspot taken in May 2010, with Earth shown to scale. The image has been colorized for aesthetic reasons. This image with 0.1 arcsecond resolution from the Swedish 1-m Solar Telescope represents the limit of what is currently possible in terms of spatial resolution.
CREDIT: The Royal Swedish Academy of Sciences, V.M.J. Henriques (sunspot), NASA Apollo 17 (Earth)

Learning more about solar storms

Solar flares directed at Earth can cause temporary radio-communication blackouts. CMEs have even greater destructive potential; they can spawn geomagnetic storms that disrupt GPS signals, radio communications and power grids. [Sun’s Wrath: Worst Solar Storms in History]

So researchers are working hard to better understand sun storms, with the aim of one day being able to predict them with a great deal of accuracy and a long lead time. But they’re not there yet.

“We still have a long way to go to really have the kind of forecasting capabilities that we have with terrestrial weather,” Young said.

That’s not to say scientists aren’t making progress. Indeed, they’ve learned a lot about solar eruptions lately, Young said. And the knowledge base will continue to grow, he added, as a fleet of sun-watching spacecraft beam home more and more observations of Earth’s star.

“We’re really in a great time right now in terms of the data that we have,” Young said, citing the contributions of spacecraft such as NASA’s STEREO and Solar Dynamics Observatory, as well as SOHO, a collaboration between NASA and the European Space Agency. “It’s going to be pretty exciting, from a solar physics and a space weather point of view.”

All of these eyes on the sun should be treated to quite a show over the next several years. Solar activity has been ramping up over the last few months as the sun works toward a maximum in its 11-year activity cycle.

Scientists expect the peak of the current cycle, which is known as Solar Cycle 24, to come in 2013.

Solar Flares yield new secrets

The Secret Lives of Solar Flares – NASA Science.

Sept. 19, 2011: One hundred and fifty two years ago, a man in England named Richard Carrington discovered solar flares.

Secret Lives (sunspots, 200px)

Sunspots sketched by R. Carrington on Sept. 1, 1859. © R. Astronomical Society. [more]

It happened at 11:18 AM on the cloudless morning of Thursday, September 1st, 1859. Just as usual on every sunny day, the 33-year-old solar astronomer was busy in his private observatory, projecting an image of the sun onto a screen and sketching what he saw. On that particular morning, he traced the outlines of an enormous group of sunspots. Suddenly, before his eyes, two brilliant beads of white light appeared over the sunspots; they were so bright he could barely stand to look at the screen.

Carrington cried out, but by the time a witness arrived minutes later, the first solar flare anyone had ever seen was fading away.

It would not be the last. Since then, astronomers have recorded thousands of strong flares using instruments ranging from the simplest telescopes in backyard observatories to the most complex spectrometers on advanced spacecraft.  Possibly no other phenomenon in astronomy has been studied as much.

After all that scrutiny, you might suppose that everything about solar flares would be known.  Far from it.  Researchers recently announced that solar flares have been keeping a secret.

“We’ve just learned that some flares are many times stronger than previously thought,” says University of Colorado physicist Tom Woods who led the research team. “Solar flares were already the biggest explosions in the solar system—and this discovery makes them even bigger.”

Secret Lives (splash, 558px)

Click to view more videos and images in support of this story.

NASA’s Solar Dynamics Observatory (SDO), launched in February 2010, made the finding:  About 1 in 7 flares experience an “aftershock.”  About ninety minutes after the flare dies down, it springs to life again, producing an extra surge of extreme ultraviolet radiation.

“We call it the ‘late phase flare,’” says Woods.   “The energy in the late phase can exceed the energy of the primary flare by as much as a factor of four.”

What causes the late phase? Solar flares happen when the magnetic fields of sunspots erupt—a process called “magnetic reconnection.”  The late phase is thought to result when some of the sunspot’s magnetic loops re-form.  A diagram prepared by team member Rachel Hock of the University of Colorado shows how it works.

The extra energy from the late phase can have a big effect on Earth.  Extreme ultraviolet wavelengths are particularly good at heating and ionizing Earth’s upper atmosphere.  When our planet’s atmosphere is heated by extreme UV radiation, it puffs up, accelerating the decay of low-orbiting satellites.  Furthermore, the ionizing action of extreme UV can bend radio signals and disrupt the normal operation of GPS.

SDO was able to make the discovery because of its unique ability to monitor the sun’s extreme UV output in high resolution nearly 24 hours a day, 7 days a week.  With that kind of scrutiny, it’s tough to keep a secret–even one as old as this.

The original research of Woods et al may be found in the Oct. 1, 2011, issue of the Astrophysical Journal.

Author: Dr. Tony Phillips | Credit: Science@NASA

Mega space storm would kill satellites for a decade

Mega space storm would kill satellites for a decade – space – 13 September 2011 – New Scientist.

A MAJOR solar storm would not only damage Earth’s infrastructure, it could also leave a legacy of radiation that keeps killing satellites for years.

When the sun belches a massive cloud of charged particles at Earth, it can damageMovie Camera our power grids and fry satellites’ electronics. But that’s not all. New calculations suggest that a solar megastorm could create a persistent radiation problem in low-Earth orbit, disabling satellites for up to a decade after the storm first hit.

It would do this by destroying a natural buffer against radiation – a cloud of charged particles, or plasma, that normally surrounds Earth out to a distance of four times the planet’s radius.

The relatively high density of plasma in the cloud prevents the formation of electromagnetic waves that would otherwise accelerate electrons to high speeds, turning them into a form of radiation. This limits the amount of radiation in the innermost of two radiation belts that surround Earth.

But solar outbursts can erode the cloud. In October 2003, a major outburst whittled the cloud down so that it only extended to two Earth radii. A repeat of a huge outburst that occurred in 1859 – which is expected – would erode the cloud to almost nothing.

Yuri Shprits of the University of California in Los Angeles led a team that simulated how such a large storm would affect the radiation around Earth.

They found that in the absence of the cloud, electromagnetic waves accelerated large numbers of electrons to high speed in Earth’s inner radiation belt, causing a huge increase in radiation there. The inner radiation belt is densest at about 3000 kilometres above Earth’s equator, which is higher than low-Earth orbit. But the belt hugs Earth more tightly above high latitude regions, overlapping with satellites in low-Earth orbit.

Speeding electrons cause electric charge to accumulate on satellite electronics, prompting sparks and damage. Increasing the number of speeding electrons would drastically shorten the lifetime of a typical satellite, the team calculates (Space Weather, DOI: 10.1029/2011sw000662).

The researchers say that the destructive radiation could hang about for a long time, spiralling around Earth’s magnetic field lines. In 1962, a US nuclear test carried out in space flooded low-Earth orbit with radiation that lasted a decade and probably ruined several satellites.

“When you get this radiation that far in, it tends to be quite long-lived and very persistent,” says Ian Mann of the University of Alberta in Edmonton, Canada, who was not involved in the study.

Thicker metal shielding around satellite electronics would help, says Shprits. The persistent radiation would also be hazardous for astronauts and electronics on the International Space Station.

Sunspot Prediction Breakthrough

Sunspot Breakthrough – NASA Science.

August 25, 2011: Imagine forecasting a hurricane in Miami weeks before the storm was even a swirl of clouds off the coast of Africa—or predicting a tornado in Kansas from the flutter of a butterfly’s wing1 in Texas. These are the kind of forecasts meteorologists can only dream about.

Could the dream come true? A new study by Stanford researchers suggests that such forecasts may one day be possible—not on Earth, but on the sun.

“We have learned to detect sunspots before they are visible to the human eye,” says Stathis Ilonidis, a PhD student at Stanford University. “This could lead to significant advances in space weather forecasting.”

Sunspots are the “butterfly’s wings” of solar storms. Visible to the human eye as dark blemishes on the solar disk, sunspots are the starting points of explosive flares and coronal mass ejections (CMEs) that sometimes hit our planet 93 million miles away. Consequences range from Northern Lights to radio blackouts to power outages.

Sunspot Breakthrough (splash sdo, 558px)

Based on data from the Solar Dynamics Observatory, this movie shows a sunspot emerging from depth in February 2011. Visualization credit: Thomas Hartlep and Scott Winegarden, Stanford University. [video] [more]

Astronomers have been studying sunspots for more than 400 years, and they have pieced together their basic characteristics: Sunspots are planet-sized islands of magnetism that float in solar plasma. Although the details are still debated, researchers generally agree that sunspots are born deep inside the sun via the action of the sun’s inner magnetic dynamo. From there they bob to the top, carried upward by magnetic buoyancy; a sunspot emerging at the stellar surface is a bit like a submarine emerging from the ocean depths.

In the August 19th issue of Science, Ilonidis and co-workers Junwei Zhao and Alexander Kosovichev announced that they can see some sunspots while they are still submerged.

Their analysis technique is called “time-distance helioseismology2,” and it is similar to an approach widely used in earthquake studies. Just as seismic waves traveling through the body of Earth reveal what is inside the planet, acoustic waves traveling through the body of the sun can reveal what is inside the star. Fortunately for helioseismologists, the sun has acoustic waves in abundance. The body of the sun is literally roaring with turbulent boiling motions. This sets the stage for early detection of sunspots.

“We can’t actually hear these sounds across the gulf of space,” explains Ilonidis, “but we can see the vibrations they make on the sun’s surface.” Instruments onboard two spacecraft, the venerable Solar and Heliospheric Observatory (SOHO) and the newer Solar Dynamics Observatory (SDO) constantly monitor the sun for acoustic activity.

Sunspot Breakthrough (splash soho, 558px)

False-colors in this SOHO movie represent acoustic travel-time differences heralding a sunspot as it rises toward the sun’s surface in October 2003. Visualization credit: Thomas Hartlep, Stanford University. [video] [more]

Submerged sunspots have a detectable effect on the sun’s inner acoustics—namely, sound waves travel faster through a sunspot than through the surrounding plasma. A big sunspot can leapfrog an acoustic wave by 12 to 16 seconds. “By measuring these time differences, we can find the hidden sunspot.”

Ilonidis says the technique seems to be most sensitive to sunspots located about 60,000 km beneath the sun’s surface. The team isn’t sure why that is “the magic distance,” but it’s a good distance because it gives them as much as two days advance notice that a spot is about to reach the surface.

“This is the first time anyone has been able to point to a blank patch of sun and say ‘a sunspot is about to appear right there,'” says Ilonidis’s thesis advisor Prof. Phil Scherrer of the Stanford Physics Department. “It’s a big advance.”

“There are limits to the technique,” cautions Ilonidis. “We can say that a big sunspot is coming, but we cannot yet predict if a particular sunspot will produce an Earth-directed flare.”

So far they have detected five emerging sunspots—four with SOHO and one with SDO. Of those five, two went on to produce X-class flares, the most powerful kind of solar explosion. This encourages the team to believe their technique can make a positive contribution to space weather forecasting. Because helioseismology is computationally intensive, regular monitoring of the whole sun is not yet possible—”we don’t have enough CPU cycles,” says Ilonidis —but he believes it is just a matter of time before refinements in their algorithm allow routine detection of hidden sunspots.

The original research reported in this story may be found in Science magazine: “Detection of Emerging Sunspot Regions in the Solar Interior” by Ilonidis, Zhao and Kosovichev, 333 (6045): 993-996.

Author: Dr. Tony Phillips | Credit: Science@NASA

Spacecraft Sees Solar Storm Engulf Earth

Spacecraft Sees Solar Storm Engulf Earth – NASA Science.

August 18, 2011: For the first time, a spacecraft far from Earth has turned and watched a solar storm engulf our planet. The movie, released today during a NASA press conference, has galvanized solar physicists, who say it could lead to important advances in space weather forecasting.

“The movie sent chills down my spine,” says Craig DeForest of the Southwest Research Institute in Boulder, Colorado.  “It shows a CME swelling into an enormous wall of plasma and then washing over the tiny blue speck of Earth where we live.  I felt very small.”

CME Engulfs Earth (splash, 558px)

A wide-angle movie recorded by NASA’s STEREO-A spacecraft shows a solar storm traveling all the way from the sun to Earth and engulfing our planet. A 17 MB Quicktime zoom adds perspective to the main 40 MB Quicktime movie.

CMEs are billion-ton clouds of solar plasma launched by the same explosions that spark solar flares.   When they sweep past our planet, they can cause auroras, radiation storms, and in extreme cases power outages.  Tracking these clouds and predicting their arrival is an important part of space weather forecasting.

“We have seen CMEs before, but never quite like this,” says  Lika Guhathakurta, program scientist for the STEREO mission at NASA headquarters.  “STEREO-A has given us a new view of solar storms.”

STEREO-A is one of two spacecraft launched in 2006 to observe solar activity from widely-spaced locations. At the time of the storm, STEREO-A was more than 65 million miles from Earth, giving it the “big picture” view other spacecraft in Earth orbit have been missing.

When CMEs first leave the sun, they are bright and easy to see. Visibility is quickly reduced, however, as the clouds expand into the void.  By the time a typical CME crosses the orbit of Venus, it is a billion times fainter than the surface of the full Moon, and more than a thousand times fainter than the Milky Way.  CMEs that reach Earth are almost as gossamer as vacuum itself and correspondingly transparent.

CME Engulfs Earth (signup)

“Pulling these faint clouds out of the confusion of starlight and interplanetary dust has been an enormous challenge,” says DeForest.

Indeed, it took almost three years for his team to learn how to do it. Footage of the storm released today was recorded back in December 2008, and they have been working on it ever since.  Now that the technique has been perfected, it can be applied on a regular basis without such a long delay.

Alysha Reinard of NOAA’s Space Weather Prediction Center explains the benefits for space weather forecasting:

“Until quite recently, spacecraft could see CMEs only when they were still quite close to the sun. By calculating a CME’s speed during this brief period, we were able to estimate when it would reach Earth. After the first few hours, however, the CME would leave this field of view and after that we were ‘in the dark’ about its progress.”

“The ability to track a cloud continuously from the Sun to Earth is a big improvement,” she continues.  “In the past, our very best predictions of CME arrival times had uncertainties of plus or minus 4 hours,” she continues.  “The kind of movies we’ve seen today could significantly reduce the error bars.”

CME Engulfs Earth (zoom, 200px)

This 17 MB Quicktime zoom adds perspective to the main 40 MB Quicktime movie of the CME engulfing Earth.

The movies pinpoint not only the arrival time of the CME, but also its mass.  From the brightness of the cloud, researchers can calculate the gas density with impressive precision.  Their results for the Dec. 2008 event agreed with actual in situ measurements at the few percent level.  When this technique is applied to future storms, forecasters will be able to estimate its impact with greater confidence.

At the press conference, DeForest pointed out some of the movie’s highlights:   When the CME first left the sun, it was cavernous, with walls of magnetism encircling a cloud of low-density gas.   As the CME crossed the Sun-Earth divide, however, its shape changed.  The CME “snow-plowed” through the solar wind, scooping up material to form a towering wall of plasma. By the time the CME reached Earth, its forward wall was sagging inward under the weight of accumulated gas.

The kind of magnetic transformations revealed by the movie deeply impressed Guhathakurta:  “I have always thought that in heliophysics understanding the magnetic field is equivalent to the ‘dark energy’ problem of astrophysics.  Often, we cannot see the magnetic field, yet it orchestrates almost everything.   These images from STEREO give us a real sense of what the underlying magnetic field is doing.”

All of the speakers at today’s press event stressed that the images go beyond the understanding of a single event.  The inner physics of CMEs have been laid bare for the first time—a development that will profoundly shape theoretical models and computer-generated forecasts of CMEs for many years to come.

“This is what the STEREO mission was launched to do,” concludes Guhathakurta, “and it is terrific to see it live up to that promise.”

Author: Dr. Tony Phillips | Credit: Science@NASA

The Worst Solar Storms in History

The Sun’s Wrath: Worst Solar Storms in History | Sun Storms & Solar Flares | Space Weather, Carrington Event & Bastille Day Flare | Space.com.

Sunspots sketched by Richard Carrington on Sept. 1, 1859.

Credit: Royal Astronomical Society/Richard Carrington via NASA

The Carrington Event of 1859 was the first documented event of a solar flare impacting Earth. The event occurred at 11:18 a.m. EDT on Sept. 1 and is named after Richard Carrington, the solar astronomer who witnessed the event through his private observatory telescope and sketched the sun’s sunspots at the time. The flare was the largest documented solar storm in the last 500 years, NASA scientists have said.

According to NOAA, the Carrington solar storm event sparked major aurora displays that were visible as far south as the Caribbean. It also caused severe interruptions in global telegraph communications, even shocking some telegraph operators and sparking fires when discharges from the lines ignited telegraph paper, according to a NASA description.

1972: Solar Flare vs. AT&T

 

August 1972 solar flare.

Credit: NASA

The major solar flare that erupted on Aug. 4, 1972 knocked out long-distance phone communication across some states, including Illinois, according to a NASA account.

“That event, in fact, caused AT&T to redesign its power system for transatlantic cables,” NASA wrote in the account.

1989: Major Power Failures From Solar Flare

 

Damage from the March 13, 1989 geomagnetic storm caused by an intense solar flare.

Credit: NASA/PSE&G

In March 1989, a powerful solar flare set off a major March 13 power blackout in Canada that left six million people without electricity for nine hours.

According to NASA, the flare disrupted electric power transmission from the Hydro Québec generating station and even melted some power transformers in New Jersey. This solar flare was nowhere near the same scale as the Carrington event, NASA scientists said.

Sun's magnetic loops during Bastille Day storm,

Credit: NASA/TRACE

The Bastille Day event takes its name from the French national holiday since it occurred the same day on July 14, 2000. This was a major solar eruption that registered an X5 on the scale of solar flares.

The Bastille Day event caused some satellites to short-circuit and led to some radio blackouts. It remains one of the most highly observed solar storm events and was the most powerful flare since 1989.

Halloween Solar Flare of October 2003

Credit: NASA/SOHO

On Oct. 28, 2003, the sun unleashed a whopper of a solar flare. The intense sun storm was so strong it overwhelmed the spacecraft sensor measuring it. The sensor topped out at X28, already a massive flare), but later analysis found that the flare reached a peak strength of about X45, NASA has said.

The solar storm was part of a string of at least nine major flares over a two-week period.

2006: X-Ray Sun Flare for Xmas

 

Solar Flare Surprise: Pure Hydrogen Shot at Earth

Credit: NOAA’s Space Weather Prediction Center.

When a major X-class solar flare erupted on the sun on Dec. 5, 2006, it registered a powerful X9 on the space weather scale.

This storm from the sun “disrupted satellite-to-ground communications and Global Positioning System (GPS) navigation signals for about 10 minutes,” according to a NASA description.

The sun storm was so powerful it actually damaged the solar X-ray imager instrument on the GOES 13 satellite that snapped its picture, NOAA officials said.