Astronomy Cmarchesin

Releases from NASA, NASA Galex, NASA's Goddard Space Flight Center, Hubble, Hinode, Spitzer, Cassini, ESO, ESA, Chandra, HiRISE, Royal Astronomical Society, NRAO, Astronomy Picture of the Day, Harvard-Smithsonian Center For Astrophysics, etc.

Thursday, June 12, 2014

Sun Emits 3 X-class Flares in 2 Days

Three X-class flares erupted from the left side of the sun June 10-11, 2014. These images are from NASA's Solar Dynamics Observatory and show light in a blend of two ultraviolet wavelengths: 171 and 131 angstroms. The former is colorized in yellow; the latter, in red. Image Credit: NASA/SDO. Download additional high-resolution imagery from NASA Goddard's Scientific Visualization Studio

On June 11, 2014, the sun erupted with its third X-class flare in two days. The flare was classified as an X1.0 and it peaked at 5:06 a.m. EDT.  Images of the flare were captured by NASA's Solar Dynamics Observatory. All three flares originated from an active region on the sun that recently rotated into view over the left limb of the sun.

To see how this event may affect Earth, please visit NOAA's Space Weather Prediction Center at http://spaceweather.gov, the U.S. government's official source for space weather forecasts, alerts, watches and warnings.
The sun released a second X-class flare, peaking at 8:52 a.m. EDT on June 10, 2014.  This is classified as an X1.5 flare.


The sun emitted significant solar flares on June 10, 2014, peaking at 7:42 a.m. EDT and 8:52 a.m. EDT. Image Credit: NASA's Goddard Space Flight Center. Download in HD formats from Goddard's Scientific Visualization Studio

The second X-class flare of June 10, 2014, appears as a bright flash on the left side of this image from NASA’s Solar Dynamics Observatory. This image shows light in the 193-angstrom wavelength, which is typically colorized in yellow. It was captured at 8:55 a.m EDT, just after the flare peaked. Image Credit: NASA/SDO

The sun emitted a significant solar flare, peaking at 7:42 a.m. EDT on June 10, 2014. NASA's Solar Dynamics Observatory – which typically observes the entire sun 24 hours a day -- captured images of the flare.

A solar flare bursts off the left limb of the sun in this image captured by NASA's Solar Dynamics Observatory on June 10, 2014, at 7:41 a.m. EDT. This is classified as an X2.2 flare, shown in a blend of two wavelengths of light: 171 and 131 angstroms, colorized in gold and red, respectively. Image Credit: NASA/SDO/Goddard/Wiessinger.

Solar flares are powerful bursts of radiation. Harmful radiation from a flare cannot pass through Earth's atmosphere to physically affect humans on the ground. However, when intense enough, they can disturb the atmosphere in the layer where GPS and communications signals travel.

To see how this event may affect Earth, please visit NOAA's Space Weather Prediction Center at http://spaceweather.gov, the U.S. government's official source for space weather forecasts, alerts, watches and warnings.

This flare is classified as an X2.2 flare. X-class denotes the most intense flares, while the number provides more information about its strength. An X2 is twice as intense as an X1, an X3 is three times as intense, etc.
Updates will be provided as needed.

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Friday, March 14, 2014

Mid-Level Solar Flare Seen by NASA's SDO

NASA's Solar Dynamics Observatory captures images of the sun in many wavelengths of light at the same time, each of which is typically colorized in a different color. Each wavelength shows different aspects of the same event, as seen in these three images of a solar flare on March 12, 2014.Image Credit: NASA/SDO/Goddard Space Flight Center

A solar flare erupts on the far right side of the sun, in this image captured by NASA's Solar Dynamics Observatory. The flare peaked at 6:34 p.m. EDT on March 12, 2014. Image Credit: NASA/SDO/Goddard Space Flight Center

The sun emitted a mid-level solar flare, peaking at 6:34 p.m. EDT on March 12, 2014, and NASA's Solar Dynamics Observatory, or SDO, captured an image of it. Solar flares are powerful bursts of radiation. Harmful radiation from a flare cannot pass through Earth's atmosphere to physically affect humans on the ground, however -- when intense enough -- they can disturb the atmosphere in the layer where GPS and communications signals travel.

To see how this event may impact Earth, please visit NOAA's Space Weather Prediction Center at http://spaceweather.gov, the U.S. government's official source for space weather forecasts, alerts, watches and warnings.

This flare is classified as an M9.3 flare, just slightly weaker than the most intense flares, which are labeled X-class. The letters denote broad categories of strength, while the numbers provide more information. An M2 is twice as intense as an M1, an M3 is three times as intense, etc.

This M9.3 flare was emitted by an active region — a magnetically strong and complex region on the sun's surface — labeled AR 11996.  

Updates will be provided as they are available on the flare and whether there was an associated coronal mass ejection, or CME, another solar phenomenon that can send solar particles into space and affect electronic systems in satellites and on Earth. 

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Karen C. Fox
NASA's Goddard Space Flight Center, Greenbelt, Md.


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Tuesday, February 25, 2014

NASA's SDO Shows Images of Significant Solar Flare

The sun emitted a significant solar flare, peaking at 7:49 p.m. EST on Feb. 24, 2014. NASA's Solar Dynamics Observatory, which keeps a constant watch on the sun, captured images of the event.

An X-class solar flare erupted on the left side of the sun on the evening of Feb. 24, 2014. This composite image, captured at 7:59 p.m. EST, shows the sun in ultraviolet light with wavelengths of both 131 and 171 angstroms. Image Credit: NASA/SDO. Additional imagery from NASA Goddard's Scientific Visualization Studio

Solar flares are powerful bursts of radiation, appearing as giant flashes of light in the SDO images. Harmful radiation from a flare cannot pass through Earth's atmosphere to physically affect humans on the ground, however -- when intense enough -- they can disturb the atmosphere in the layer where GPS and communications signals travel.

To see how this event may impact Earth, please visit NOAA's Space Weather Prediction Center, the U.S. government's official source for space weather forecasts, alerts, watches and warnings.

These SDO images from 7:25 p.m. EST on Feb. 24, 2014, show the first moments of an X-class flare in different wavelengths of light -- seen as the bright spot that appears on the left limb of the sun. Hot solar material can be seen hovering above the active region in the sun's atmosphere, the corona. Image Credit: NASA/SDO. Additional imagery from NASA Goddard's Scientific Visualization Studio

This flare is classified as an X4.9-class flare. X-class denotes the most intense flares, while the number provides more information about its strength. An X2 is twice as intense as an X1, an X3 is three times as intense, etc.

Updates will be provided as needed.

Related Links

Karen C. Fox
NASA's Goddard Space Flight Center, Greenbelt, Md.


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Tuesday, February 04, 2014

Sun Spits Out Mid-Level Solar Flare

A mid-level solar flare erupted on the sun late on Feb. 3, 2014, peaking at midnight EST. This image, captured by NASA's Solar Dynamics Observatory, shows the bright flare near the center of the sun. Image Credit: NASA/SDO
This image of an M5.2-class solar flare that occurred late on Feb. 3, 2014, was captured by NASA’s Solar Dynamics Observatory. The solar flare can be seen as the bright flash near the center of the sun. The image shows light in the 304 Angstrom wavelength, which is typically colorized in red. Image Credit: NASA/SDO

Solar flares are powerful bursts of radiation. Harmful radiation from a flare cannot pass through Earth's atmosphere to physically affect humans on the ground, however -- when intense enough -- they can disturb the atmosphere in the layer where GPS and communications signals travel.

To see how this event may impact Earth, please visit NOAA's Space Weather Prediction Center at http://spaceweather.gov, the U.S. government's official source for space weather forecasts, alerts, watches and warnings.

This flare is classified as an M5.2 flare. Updates will be provided as needed.


Karen C. Fox
NASA's Goddard Space Flight Center, Greenbelt, Md.


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Thursday, January 30, 2014

NASA's SDO Sees Lunar Transit

 
A rainbow of lunar transits as seen by NASA's Solar Dynamics Observatory. The observatory watches the sun in many different wavelengths of light, which are each colorized in a different color. Image Credit: NASA/SDO
On Jan 30, 2014, beginning at 8:31 a.m EST, the moon moved between NASA’s Solar Dynamics Observatory, or SDO, and the sun, giving the observatory a view of a partial solar eclipse from space. Such a lunar transit happens two to three times each year.  This one lasted two and one half hours, which is the longest ever recorded.  When the next one will occur is as of yet unknown due to planned adjustments in SDO's orbit.

Note in the picture how crisp the horizon is on the moon, a reflection of the fact that the moon has no atmosphere around it to distort the light from the sun.
NASA's Solar Dynamics Observatory captured this image of the moon crossing in front of its view of the sun on Jan. 30, 2014, at 9:00 a.m. EST. Image Credit: NASA/SDO

A movie of the moon crossing in front of the sun as seen by NASA’s Solar Dynamics Observatory on Jan 30, 2014. The sun appears to move because SDO’s fine guidance systems rely on seeing the whole sun to keep the images centered from exposure to exposure. Image Credit: NASA/SDO/Goddard Space Flight Center

Related Links:


Karen C. Fox
NASA's Goddard Space Flight Center, Greenbelt, Md.


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Wednesday, November 20, 2013

X-Class Solar Flare

Adding on to a series of solar flares throughout October and November, the sun emitted another significant solar flare on Nov. 19, 2013, peaking at 5:26 a.m. EST. Solar flares are powerful bursts of radiation. Harmful radiation from a flare cannot pass through Earth's atmosphere to physically affect humans on the ground, however -- when intense enough -- they can disturb the atmosphere in the layer where GPS and communications signals travel.
 
An X1-class flare erupts from the right side of the sun in this image captured by NASA's Solar Dynamics Observatory on Nov. 19, 2013. The flare erupted from a region that produced many flares in its two-week journey across the face of the sun, and is shown here just before rotating out of view.Image Credit: NASA/SDO

 To see how this event may impact Earth, please visit NOAA's Space Weather Prediction Center, the U.S. government's official source for space weather forecasts, alerts, watches and warnings.

This flare is classified as an X1.0 class flare. "X-class" denotes the most intense flares, while the number provides more information about its strength. An X2 is twice as intense as an X1, an X3 is three times as intense, etc.

This flare came from an active region numbered AR 1893 that is just rotating out of sight over the sun's right side. Increased numbers of flares are quite common at the moment, since the sun's normal 11-year activity cycle is ramping up toward solar maximum conditions. Humans have tracked this solar cycle continuously since it was discovered in 1843, and it is normal for there to be many flares a day during the sun's peak activity.

Updates will be provided as needed.

Karen C. Fox
NASA's Goddard Space Flight Center, Greenbelt, Md.



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Saturday, October 26, 2013

NASA Releases Movie of Sun's Canyon of Fire


Images of a gigantic filament eruption on the sun were captured on Sept. 29-30, 2013, by NASA's Solar Dynamics Observatory, or SDO. Image Credit:NASA/SDO. › View Promo Image

A magnetic filament of solar material erupted on the sun in late September, breaking the quiet conditions in a spectacular fashion. The 200,000 mile long filament ripped through the sun's atmosphere, the corona, leaving behind what looks like a canyon of fire. The glowing canyon traces the channel where magnetic fields held the filament aloft before the explosion.  Visualizers at NASA's Goddard Space Flight Center in Greenbelt, Md. combined two days of satellite data to create a short movie of this gigantic event on the sun.

In reality, the sun is not made of fire, but of something called plasma: particles so hot that their electrons have boiled off, creating a charged gas that is interwoven with magnetic fields.

These images were captured on Sept. 29-30, 2013, by NASA's Solar Dynamics Observatory, or SDO, which constantly observes the sun in a variety of wavelengths.

Different wavelengths help capture different aspect of events in the corona. The red images shown in the movie help highlight plasma at temperatures of 90,000° F and are good for observing filaments as they form and erupt. The yellow images, showing temperatures at 1,000,000° F, are useful for observing material coursing along the sun's magnetic field lines, seen in the movie as an arcade of loops across the area of the eruption. The browner images at the beginning of the movie show material at temperatures of 1,800,000° F, and it is here where the canyon of fire imagery is most obvious.  By comparing this with the other colors, one sees that the two swirling ribbons moving farther away from each other are, in fact, the footprints of the giant magnetic field loops, which are growing and expanding as the filament pulls them upward.

The movie runs 2.3 minutes and is available for download in high resolution at: http://svs.gsfc.nasa.gov/goto?11379

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Karen C. Fox
NASA's Goddard Space Flight Center, Greenbelt, Md.


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Friday, October 25, 2013

NASA's SDO Sees Sun Emit a Mid-level Solar Flare

NASA's Solar Dynamics Observatory or SDO, captured this image on the sun of an M9.4-class solar flare, which peaked at 8:30 pm EDT on Oct. 23, 2013. The image displays light in the wavelength of 131 Angstroms, which is good for viewing the intense heat of a solar flare and typically colored teal. Image Credit: NASA/SDO. › View full disk image

The sun emitted a mid-level solar flare that peaked at 8:30 pm EDT on Oct. 23, 2013. Solar flares are powerful bursts of radiation. Harmful radiation from a flare cannot pass through Earth's atmosphere to physically affect humans on the ground, however -- when intense enough -- they can disturb the atmosphere in the layer where GPS and communications signals travel. Such radiation can disrupt radio signals for as long as the flare is ongoing, anywhere from minutes to hours.

To see how this event may impact Earth, please visit NOAA's Space Weather Prediction Center at http://spaceweather.gov, the U.S. government's official source for space weather forecasts, alerts, watches and warnings.

This flare is classified as an M9.4 flare, on a scale from M1 to M9.9.  This rating puts it at the very top of the scale for M class flares, which are the weakest flares that can cause some space weather effects near Earth. In the past, they have caused brief radio blackouts at the poles.  The next highest level is X-class, which denotes the most intense flares.

Increased numbers of flares are quite common at the moment, since the sun is near solar maximum. Humans have tracked solar cycles continuously since they were discovered in 1843, and it is normal for there to be many flares a day during the sun's peak activity.


Karen C. Fox
NASA's Goddard Space Flight Center, Greenbelt, Md. 


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Monday, June 24, 2013

Solar Splashdown

This photograph from NASA's Solar Dynamics Observatory catches the beginning of the eruption that took place on June 7, 2011. At lower right, dark filaments of solar plasma arc away from the Sun. The plasma lofted off, then rained back down to create "hot spots" that glowed in ultraviolet light. This representative-color image shows light at a wavelength of 171 Angstroms (17.1 nm). Credit: NASA / SDO / P. Testa (CfA).  High Resolution Image (jpg) - Low Resolution Image (jpg)
 
This photograph from NASA's Solar Dynamics Observatory catches the beginning of the eruption that took place on June 7, 2011. It shows light at a wavelength of 304 Angstroms (30.4 nm). A bright flare is visible at lower right, as well as hot, glowing plasma blasting outward.Credit: NASA / SDO / P. Testa (CfA). High Resolution Image (jpg) - Low Resolution Image (jpg)

Cambridge, MA - On June 7, 2011, our Sun erupted, blasting tons of hot plasma into space. Some of that plasma splashed back down onto the Sun's surface, sparking bright flashes of ultraviolet light. This dramatic event may provide new insights into how young stars grow by sucking up nearby gas. 

The eruption and subsequent splashdown were observed in spectacular detail by NASA's Solar Dynamics Observatory. This spacecraft watches the Sun 24 hours a day, providing images with better-than-HD resolution. Its Atmospheric Imaging Assembly instrument was designed and developed by researchers at the Harvard-Smithsonian Center for Astrophysics (CfA).

"We’re getting beautiful observations of the Sun. And we get such high spatial resolution and high cadence that we can see things that weren’t obvious before," says CfA astronomer Paola Testa.

Movies of the June 7th eruption show dark filaments of gas blasting outward from the Sun's lower right. Although the solar plasma appears dark against the Sun's bright surface, it actually glows at a temperature of about 18,000 degrees Fahrenheit. When the blobs of plasma hit the Sun's surface again, they heat up by a factor of 100 to a temperature of almost 2 million degrees F. As a result, those spots brighten in the ultraviolet by a factor of 2 – 5 over just a few minutes.

The tremendous energy release occurs because the in falling blobs are traveling at high speeds, up to 900,000 miles per hour (400 km/sec). Those speeds are similar to the speeds reached by material falling onto young stars as they grow via accretion. Therefore, observations of this solar eruption provide an "up close" view of what happens on distant stars.

"We often study young stars to learn about our Sun when it was an 'infant.' Now we’re doing the reverse and studying our Sun to better understand distant stars," notes Testa.

These new observations, combined with computer modeling, have helped resolve a decade-long argument over how to measure the accretion rates of growing stars. Astronomers calculate how fast a young star is gathering material by observing its brightness at various wavelengths of light, and how that brightness changes over time. However, they got higher estimates from optical and ultraviolet light than from X-rays.

The team discovered that the ultraviolet flashes they observed came from the in falling material itself, not the surrounding solar atmosphere. If the same is true for distant, young stars, then by analyzing the ultraviolet light they emit, we can learn about the material they are accreting.

"By seeing the dark spots on the Sun, we can learn about how young stars accrete material and grow." explains Testa.

These results were published in the online journal Science Express.

Headquartered in Cambridge, Mass., the Harvard-Smithsonian Center for Astrophysics (CfA) is a joint collaboration between the Smithsonian Astrophysical Observatory and the Harvard College Observatory. CfA scientists, organized into six research divisions, study the origin, evolution and ultimate fate of the universe.

For more information, contact:

David A. Aguilar
Director of Public Affairs
Harvard-Smithsonian Center for Astrophysics
617-495-7462

daguilar@cfa.harvard.edu

 
Christine Pulliam
Public Affairs Specialist
Harvard-Smithsonian Center for Astrophysics
617-495-7463

cpulliam@cfa.harvard.edu
 

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Monday, June 03, 2013

NASA IRIS: Improving Our View Of the Sun

This image from the Japan Aerospace Exploration Agency’s Hinode mission shows the lower regions of the sun’s atmosphere, the interface region, which a new mission called the Interface Region Imaging Spectrograph, or IRIS, will study in exquisite detail. Where previous missions have been able to image material at only a few predetermined temperatures in this region, IRIS will observe a wide range of temperatures from 5,000 kelvins to 65,000 kelvins (8,540 F to 116,540 F), and up to 10 million kelvins (about 18 million F) during solar flares. Its images will resolve structures down to 150 miles across. Credit: JAXA/Hinod.   › View larger

In late June 2013, NASA will launch a new set of eyes to offer the most detailed look ever of the sun’s lower atmosphere, called the interface region. This region is believed to play a crucial role in powering the sun’s dynamic million-degree atmosphere, the corona. The Interface Region Imaging Spectrograph or IRIS mission will provide the best resolution so far of the widest range of temperatures for of the interface region, an area that has historically been difficult to study.

"This region is crucial for understanding how the corona gets so hot,” said Joe Davila, IRIS project scientist at NASA's Goddard Space Flight Center in Greenbelt, Md. "For the first time, we will have the capability to observe it at fundamental physical scale sizes and see details that have previously been hidden."

IRIS’s capabilities are uniquely tailored to unravel the interface region by providing both high-resolution images and a kind of data known as spectra.

For its high-resolution images, IRIS will capture data on about one percent of the sun at a time. While these are relatively small snapshots, IRIS will be able to see very fine features, as small as 150 miles across.

“We have some great space observatories currently looking at the sun,” said Bart DePontieu, the IRIS science lead at Lockheed Martin in Palo Alto, Calif. “But when it comes to the interface region, we’ve never been able to resolve individual structures. We have been able only to see conglomerates of various structures. Now we will finally be able to observe the details.”

IRIS’s images will be three to four times as detailed as the images from NASA’s Solar Dynamics Observatory – though SDO can observe the whole sun at once. SDO’s wavelengths are not tailored, however, to see the interface region. Scientists can use IRIS observations to hone in on smaller details while working with the larger instruments, such as SDO or the Japan Aerospace Exploration Agency’s Hinode, to capture images of the entire sun. Together, the observatories will explore how the corona works and impacts Earth – SDO and Hinode monitoring the solar surface and outer atmosphere, with IRIS watching the region in between.


These movies use data from the Japan Aerospace Exploration Agency’s Hinode mission to provide an example of IRIS’ improved resolution over previous observations. Credit: JAXA/Hinode/De Pontieu.  › Download video 

Ultraviolet images look at only one wavelength of light at a time, but IRIS will also provide spectra, a kind of data that can show information about many wavelengths of light at once. Spectrographs split the sun’s light into its various wavelengths and measure how much of any given wavelength is present. This is then portrayed on a graph showing spectral "lines" – taller lines correspond to wavelengths in which the sun emits relatively more radiation.

Each spectral line also corresponds to a given temperature, so this provides information about how much material of a particular temperature is present. The images from IRIS' telescope will record observations of material at specific temperatures, ranging from 5,000 kelvins to 65,000 kelvins (8,540 F to 116,540 F) -- and up to 10 million kelvins (about 18 million F) during solar flares -- a range best suited to observe material on the sun's surface and in the interface region.

“By looking at spectra of material in these temperature ranges, we can also diagnose velocity and perhaps density of the material, too,” said De Pontieu.

The IRIS instrument will capture a new image every five to 10 seconds, and spectra about once every two seconds. These unique capabilities will be coupled with state-of-the-art 3-D numerical modeling sophisticated enough to deal with the complexity of this region. The modeling makes use of supercomputers at NASA’s Ames Research Center, Moffet Field, Calif.

In combination, IRIS’ resolution, fast imaging rate, wide temperature coverage and computer modeling will enable scientists for the first time to track solar material as it is accelerated and heated in the interface region and thus help pinpoint where and how the plasma gains energy and heat along its travels through the lower levels of the solar atmosphere.

IRIS was developed by Lockheed Martin as a NASA Small Explorer mission. The NASA Explorer Program is designed to provide frequent, low-cost access to space for heliophysics and astrophysics missions using small- to mid-sized spacecraft. Goddard manages the Explorer Program for the agency’s Science Mission Directorate in Washington. Major contributions for IRIS were provided by Lockheed Martin Sensing and Exploration Systems, NASA’s Ames Research Center, Smithsonian Astrophysical Observatory, Montana State University, Stanford University, the Norwegian Space Centre and the University of Oslo.

For more information about NASA's IRIS mission, please visit: http://www.nasa.gov/iris

 
Karen C. Fox
NASA's Goddard Space Flight Center, Greenbelt, Md.



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Tuesday, May 14, 2013

Three X-class Flares in 24 Hours

 Third Update: May 14, 9 a.m. EDT

The sun emitted a third significant solar flare in under 24 hours, peaking at 9:11 p.m. EDT on May 13, 2013. This flare is classified as an X3.2 flare. This is the strongest X-class flare of 2013 so far, surpassing in strength the two X-class flares that occurred earlier in the 24-hour period.

The flare was also associated with a coronal mass ejection, or CME. The CME began at 9:30 p.m. EDT and was not Earth-directed. Experimental NASA research models show that the CME left the sun at approximately 1,400 miles per second, which is particularly fast for a CME. The models suggest that it will catch up to the two CMEs associated with the earlier flares. The merged cloud of solar material will pass by the Spitzer spacecraft and may give a glancing blow to the STEREO-B and Epoxi spacecraft. Their mission operators have been notified. If warranted, operators can put spacecraft into safe mode to protect the instruments from solar material.

These pictures from NASA's Solar Dynamics Observatory show the three X-class flares that the sun emitted in under 24 hours on May 12-13, 2013. The images show light with a wavelength of 131 angstroms, which is particularly good for showing solar flares and is typically colorized in teal. Credit: NASA/SDO.  › Larger image - › Unlabeled image
 
Four images from NASA's Solar Dynamics Observatory of an X3.2-class flare from late at night on May 13, 2013. Starting in the upper left and going clockwise, the images show light in the 304-, 335-, 193- and 131-angstrom wavelengths. By looking at the sun in different wavelengths, scientists can view solar material at different temperatures, and thus learn more about what causes flares. Credit: NASA/SDO.  › Larger image  -  › Unlabeled image 

Second Update: May 13, 3:30 p.m. EDT

The X2.8-class flare was also associated with a coronal mass ejection, or CME, another solar phenomenon that can send billions of tons of solar particles into space, which can potentially affect electronic systems in satellites and on the ground. The CME was not Earth-directed, but could pass NASA's STEREO-B, Messenger and Spitzer spacecraft. Their mission operators have been notified. Experimental NASA research models show that the CME left the sun at 1,200 miles per second beginning at 12:18 p.m. EDT. If warranted, operators can put spacecraft into safe mode to protect the instruments from solar material.


On May 12-13, 2013, the sun erupted with an X1.7-class and an X2.8-class flare, as well as two coronal mass ejections, or CMEs, off the upper left side of the sun. Solar material also danced and blew off the sun in what’s called a prominence eruption on the lower right side of the sun. This movie compiles imagery of this activity from NASA's Solar Dynamics Observatory and from NASA and the European Space Agency's Solar and Heliospheric Observatory.  Credit: NASA/SDO/ESA/SOHO. Music: "Long Range Cruise" by Lars Leonhard, courtesy of the artist and BineMusic. › Download video in HD formats

First Update: May 13, 1:30 p.m. EDT

On May 13, 2013, the sun emitted an X2.8-class flare, peaking at 12:05 p.m. EDT. This is the the strongest X-class flare of 2013 so far, surpassing in strength the X1.7-class flare that occurred 14 hours earlier. It is the 16th X-class flare of the current solar cycle and the third-largest flare of that cycle. The second-strongest was an X5.4 event on March 7, 2012. The strongest was an X6.9 on Aug. 9, 2011.

On May 13, 2013, an X2.8-class flare erupted from the sun -- the strongest flare of 2013 to date. This image of the flare, shown in the upper left corner, was captured by NASA's Solar Dynamics Observatory in light of 131 angstroms, a wavelength which is particularly good for capturing the intense heat of a solar flare and which is typically colorized in teal. Credit: NASA/SDO. › Larger image

Original Story: May 13

On May 12, 2013, the sun emitted a significant solar flare, peaking at 10 p.m. EDT. This flare is classified as an X1.7, making it the first X-class flare of 2013. The flare was also associated with another solar phenomenon, called a coronal mass ejection (CME) that can send solar material out into space. This CME was not Earth-directed.

The sun erupted with an X1.7-class solar flare on May 12, 2013. This is a blend of two images of the flare from NASA's Solar Dynamics Observatory: One image shows light in the 171-angstrom wavelength, the other in 131 angstroms. Credit: NASA/SDO/AIA.  › Larger image

"X-class" denotes the most intense flares, while the number provides more information about its strength. An X2 is twice as intense as an X1, an X3 is three times as intense, etc.

This flare erupted from an active region just out of sight over the left side of the sun, a region that will soon rotate into view. This region has produced two smaller M-class flares as well.

The May 12 flare was also associated with a coronal mass ejection, another solar phenomenon that can send billions of tons of solar particles into space, which can affect electronic systems in satellites and on the ground. Experimental NASA research models show that the CME left the sun at 745 miles per second and is not Earth-directed, however its flank may pass by the STEREO-B and Spitzer spacecraft, and their mission operators have been notified. If warranted, operators can put spacecraft into safe mode to protect the instruments from solar material. There is some particle radiation associated with this event, which is what can concern operators of interplanetary spacecraft since the particles can trip computer electronics on board.

Increased numbers of flares are quite common at the moment because the sun's normal 11-year activity cycle is ramping up toward solar maximum, which is expected in 2013. Humans have tracked the solar cycle continuously since it was discovered in 1843, and it is normal for there to be many flares a day during the sun's peak activity. The first X-class flare of the current solar cycle occurred on Feb. 15, 2011, and there have been another 15 X-class flares since, including this one. The largest X-class flare in this cycle was an X6.9 on Aug. 9, 2011.

NOAA's Space Weather Prediction Center (http://swpc.noaa.gov) is the U.S. government's official source for space weather forecasts, alerts, watches and warnings.

What is a solar flare?

For answers to these and other space weather questions, please visit the Space Weather Frequently Asked Questions page.


Related Links

 › View Past Solar Activity
Karen C. Fox
NASA's Goddard Space Flight Center, Greenbelt, Md.


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Tuesday, April 23, 2013

Three Years of SDO Images

In the three years since it first provided images of the sun in the spring of 2010, NASA’s Solar Dynamics Observatory has had virtually unbroken coverage of the sun's rise toward solar maximum, the peak of solar activity in its regular 11-year cycle. This video shows those three years of the sun at a pace of two images per day.


Credit: NASA's Goddard Space Flight Center
 
SDO’s Atmospheric Imaging Assembly captures a shot of the sun every 12 seconds in 10 different wavelengths. The images shown here are based on a wavelength of 171 angstroms, which is in the extreme ultraviolet range and shows solar material at around 600,000 kelvins (about 1.08 million F). In this wavelength it is easy to see the sun’s 25-day rotation as well as how solar activity has increased over three years.

During the course of the video, the sun subtly increases and decreases in apparent size. This is because the distance between the SDO spacecraft and the sun varies over time. The image is, however, remarkably consistent and stable despite the fact that SDO orbits Earth at 6,876 mph and Earth orbits the sun at 67,062 mph.

This image is a composite of 25 separate images spanning the period of April 16, 2012, to April 15, 2013. It uses the SDO AIA wavelength of 171 angstroms and reveals the zones on the sun where active regions are most common during this part of the solar cycle. Credit: NASA/SDO/AIA/S. Wiessinger.  › Larger image
  
Such stability is crucial for scientists, who use SDO to learn more about our closest star. These images have regularly caught solar flares and coronal mass ejections in the act, types of space weather that can send radiation and solar material toward Earth and interfere with satellites in space. SDO’s glimpses into the violent dance on the sun help scientists understand what causes these giant explosions -- with the hopes of some day improving our ability to predict this space weather. 

Karen C. Fox and Scott Wiessinger
NASA's Goddard Space Flight Center, Greenbelt, Md.



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Monday, February 25, 2013

NASA's SDO Observes Fast-Growing Sunspot

The bottom two black spots on the sun, known as sunspots, appeared quickly over the course of Feb. 19-20, 2013. These two sunspots are part of the same system and are over six Earths across. This image combines images from two instruments on NASA's Solar Dynamics Observatory (SDO): the Helioseismic and Magnetic Imager (HMI), which takes pictures in visible light that show sunspots and the Advanced Imaging Assembly (AIA), which took an image in the 304 Angstrom wavelength showing the lower atmosphere of the sun, which is colorized in red. Credit: NASA/SDO/AIA/HMI/Goddard Space Flight Center.  › View larger

As magnetic fields on the sun rearrange and realign, dark spots known as sunspots can appear on its surface. Over the course of Feb. 19-20, 2013, scientists watched a giant sunspot form in under 48 hours. It has grown to over six Earth diameters across but its full extent is hard to judge since the spot lies on a sphere not a flat disk.

The spot quickly evolved into what's called a delta region, in which the lighter areas around the sunspot, the penumbra, exhibit magnetic fields that point in the opposite direction of those fields in the center, dark area. This is a fairly unstable configuration that scientists know can lead to eruptions of radiation on the sun called solar flares.

Karen C. Fox
NASA’s Goddard Space Flight Center


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Tuesday, February 12, 2013

Year Three: NASA SDO Mission Highlights



The sun's greatest hits as captured by the Solar Dynamic Observatory from February 2012 to February 2013. Credit: NASA/GSFC. › Download video

On Feb. 11, 2010, NASA launched an unprecedented solar observatory into space. NASA's Solar Dynamics Observatory (SDO) flew up on an Atlas V rocket, carrying instruments that scientists hoped would revolutionize observations of the sun. If all went according to plan, SDO would provide incredibly high-resolution data of the entire solar disk almost as quickly as once a second.

When the science team released its first images in April of 2010, SDO's data exceeded everyone’s hopes and expectations, providing stunningly detailed views of the sun. In the three years since then, SDO's images have continued to show breathtaking pictures and movies of eruptive events on the sun. Such imagery is more than just pretty, they are the very data that scientists study. By highlighting different wavelengths of light, scientists can track how material on the sun moves. Such movement, in turn, holds clues as to what causes these giant explosions, which, when Earth-directed, can disrupt technology in space.

In its third year of observations, however, SDO has also opened up several new, unexpected doors to scientific inquiry. Over the last year scientists spent much time poring over data from comet observations. Comets that travel close to the sun – known as sun-grazers -- have long been observed as they move toward the sun, but the view was always obscured by the sun's bright light when the comets got too close. But SDO has now captured images of two comets as they passed close to the sun.

One of the highlights of NASA's Solar Dynamics Observatory (SDO) during its third year in space: observations of Venus' transit across the Sun. This image was taken just as Venus was leaving the disk of the sun at 12:15 a.m. EDT on Jun. 6, 2012. Credit: NASA/SDO/HMI.  › View larger

In December 2011, Comet Lovejoy swept right through the sun's corona, with its long tail streaming behind it. SDO sent back pictures of the comet's long tail being buffeted by systems around the sun. Such comet tails move in response to the sun's otherwise invisible magnetic field, so they can also act as tracers of the complex magnetic field higher up in the corona, offering scientists a unique way of observing movement there. Observations of the comet's long trail of water vapor and the material its lost, as well as how it vaporizes in the intense radiation of the sun could also be used to study atomic material and their ratios in the corona. SDO's third year, therefore, brought two research communities together: comet researchers who can use solar observations for their studies and solar scientists who can use comet observations to study the sun.

The second novel highlight of SDO's third year occurred on June 5, 2012, when Venus crossed in front of the sun, as viewed from Earth – an occurrence that will not happen again for more than 100 years. SDO cameras trained on the transit to help calibrate its instruments and to learn more about Venus's atmosphere. Since the points at which Venus first touched and later left the sun are known down to minute detail, SDO could use this information to make sure its images are oriented to true solar north – calibrating its orientation to within a tenth of a pixel. Scientists also recorded how the sun's extreme ultraviolet light traveled through Venus's atmosphere in order to learn more about what elements exist around the planet.

The third new area of SDO data came from an always-planned source, the helioseismic and magnetic imager (HMI). The instrument provides real time maps of magnetic fields of the entire surface of the sun, showing how strong they are and – for the first time ever -- in which direction they are pointing. Since HMI is providing a type of data never before collected, and so it has opened up a whole new area of inquiry. Changing and realigning magnetic fields are at the heart of the sun's eruptions, so this too is a crucial set of data. Scientists have spent time over the last year to figure out how to best create visual maps from the data – as well as how to interpret them. The HMI images have been affectionately referred to as "hedgehog pictures" since they show spiky quill like lines pointing out of – or in toward – the sun.
  
White lines represent magnetic field lines looping up out of the sun's surface in this image from SDO's Helioseismological and Magnetic Imager (HMI). Credit: NASA/SDO/HMI. › View larger
 
Studying such complex magnetic motions inside the sun can help scientists understand the complex magnetic fields around the sun, which lead to the eruptions that can cause space weather effects near Earth and other objects in the solar system. Ultimately research into these constantly changing magnetic fields may lead to advance warning of such activity, which can send radiation, particles, and magnetic fields toward Earth and sometimes disrupt technology at Earth and other planets.

SDO is the first mission in a NASA’s Living With a Star program, the goal of which is to develop the scientific understanding necessary to address those aspects of the sun-Earth system that directly affect our lives and society. NASA’s Goddard Space Flight Center in Greenbelt, Md. built, operates, and manages the SDO spacecraft for NASA's Science Mission Directorate in Washington, D.C.

For high resolution media, visit:  http://svs.gsfc.nasa.gov/vis/a010000/a011200/a011203/
 
For more information about NASA's SDO spacecraft, visit:  http://www.nasa.gov/sdo
 
Karen C. Fox
NASA’s Goddard Space Flight Center

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Tuesday, January 15, 2013

New Sunspots Producing Space Weather

 
This triptych shows a coronal mass ejection or CME as it burst off of the sun in the morning of Jan. 13, 2013. The images were captured by NASA's Solar Terrestrial Relations Observatory (STEREO). Credit: NASA/STEREO.  › View full image

This image from NASA's Solar Dynamics Observatory was captured on Jan. 13, 2013, at 8:13 p.m. EST. At the center sits a large cluster of sunspots, dubbed Active Region 11654, that rotated over the left limb of the sun on Jan. 10. The region has been responsible for a spate of mild space weather and is now about 120,000 miles end-to-end, which equates to around 14 Earths. Credit: NASA/SDO/HMI.  › View larger

On Jan. 13, 2013, at 2:24 a.m. EST, the sun erupted with an Earth-directed coronal mass ejection or CME. Not to be confused with a solar flare, a CME is a solar phenomenon that can send solar particles into space and reach Earth one to three days later.

Experimental NASA research models, based on observations from the Solar Terrestrial Relations Observatory (STEREO) and the ESA/NASA mission the Solar and Heliospheric Observatory, show that the CME left the sun at speeds of 275 miles per second. This is a fairly typical speed for CMEs, though much slower than the fastest ones, which can be almost ten times that speed.

 When Earth-directed, CMEs can cause a space weather phenomenon called a geomagnetic storm, which occurs when they successfully connect up with the outside of the Earth's magnetic envelope, the magnetosphere, for an extended period of time. In the past, CMEs of this speed have not caused substantial geomagnetic storms. They have caused auroras near the poles but are unlikely to affect electrical systems on Earth or interfere with GPS or satellite-based communications systems.

 Two active regions -- named AR 11652 and AR 11654 by the National Oceanic and Atmospheric Administration (NOAA) – have produced four low-level M-class flares since Jan. 11. Solar flares are powerful bursts of light and radiation. Harmful radiation from a flare cannot pass through Earth's atmosphere to physically affect humans on the ground, however, when intense enough, they can disturb the atmosphere in the layer where GPS and communications signals travel. M-class flares are the weakest flares that can still cause some space weather effects near Earth. The recent flares caused weak radio blackouts and their effects have already subsided.

 NOAA's Space Weather Prediction Center (http://swpc.noaa.gov) is the United States Government official source for space weather forecasts.

 Updates will be provided if needed.

What is a CME?
 For answers to this and other space weather questions, please visit the Spaceweather Frequently Asked Questions page.

 
Karen C. Fox
NASA's Goddard Space Flight Center, Greenbelt, Md.

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Tuesday, November 27, 2012

Solar Minimum; Solar Maximum

The picture on the left shows a calm sun from Oct. 2010. The right side, from Oct. 2012, shows a much more active and varied solar atmosphere as the sun moves closer to peak solar activity, a peak known as solar maximum, predicted for 2013. Both images were captured by NASA's Solar Dynamics Observatory (SDO) observing light emitted from the 1 million degree plasma, which is a good temperature for observing the quiet corona. Credit: NASA/SDO.   View larger

The sun goes through a natural solar cycle approximately every 11 years. The cycle is marked by the increase and decrease of sunspots -- visible as dark blemishes on the sun's surface, or photosphere. The greatest number of sunspots in any given solar cycle is designated as "solar maximum." The lowest number is "solar minimum."

The solar cycle provides more than just increased sunspots, however. In the sun's atmosphere, or corona, bright active regions appear, which are rooted in the lower sunspots. Scientists track the active regions since they are often the origin of eruptions on the sun such as solar flares or coronal mass ejections.

The most recent solar minimum occurred in 2008, and the sun began to ramp up in January 2010, with an M-class flare (a flare that is 10 times less powerful than the largest flares, labeled X-class). The sun has continued to get more active, with the next solar maximum predicted for 2013.

The journey toward solar maximum is evident in current images of the sun, showing a marked difference from those of 2010, with bright active regions dotted around the star.

High resolution imagery from this article is available at: http://svs.gsfc.nasa.gov/vis/a010000/a011000/a011072/index.html.


Karen C. Fox
NASA Goddard Space Flight Center, Greenbelt, MD

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Tuesday, November 13, 2012

Sun Emits a Mid-level Flare

By observing the sun in a number of different wavelengths, NASA's telescopes can tease out different aspects of events on the sun. These three images of a solar flare on Nov. 13, 2012, captured by NASA's Solar Dynamics Observatory (SDO), show from left to right: light in the 304 Ångstrom wavelength, which shows light from the region of the sun's atmosphere where flares originate; light from the sun in the 193 Ångstrom wavelength, which shows the hotter material of a solar flare; and light in 335 Ångstroms, which highlights light from active regions in the corona. Credit: NASA/SDO/Goddard Space Flight Center . View larger

 On Nov. 13, 2012, the sun emitted a mid-level solar flare, peaking at 9:04 p.m. EST.

 Solar flares are powerful bursts of radiation. Harmful radiation from a flare cannot pass through Earth's atmosphere to physically affect humans on the ground, however -- when intense enough -- they can disturb the atmosphere in the layer where Global Positioning System (GPS) and communications signals travel. This disrupts the radio signals for as long as the flare is ongoing, anywhere from minutes to hours.

 This flare is classified as an M6 flare. M-class flares are the weakest flares that can still cause some space weather effects near Earth. They can cause brief radio blackouts at the poles. This M-class flare caused a radio blackout categorized according to the National Oceanic and Atmospheric Association's Space Weather Scales as R2 -- or "moderate" -- on a scale of R1 to R5. It has since subsided.

 Increased numbers of flares are quite common at the moment, since the sun's normal 11-year activity cycle is ramping up toward solar maximum, which is expected in 2013. Humans have tracked this solar cycle continuously since it was discovered in 1843, and it is normal for there to be many flares a day during the sun's peak activity.

 The flare was not associated with a coronal mass ejection (CME), another solar phenomenon that can send solar particles into space and can reach Earth one to three days later.

 Updates will be provided as needed.

Visible in the lower left corner, the sun emitted an M6 solar flare on Nov. 13, 2012, which peaked at 9:04 p.m. EST. This image is a blend of two images captured by NASA's Solar Dynamics Observatory (SDO), one showing the sun in the 304 Angstrom wavelength and one in the 193 Angstrom wavelength. Credit: NASA/SDO . View larger

What is a solar flare?
For answers to this and other space weather questions, please visit the Spaceweather Frequently Asked Questions page

Related Links 

Karen C. Fox
NASA's Goddard Space Flight Center, Greenbelt, Md.

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Saturday, October 27, 2012

STEREO Reaches New Milestone At Its Sixth Anniversary

Each of these images was captured from a different perspective by one of NASA's Solar Terrestrial Relations Observatory (STEREO) spacecraft on Oct. 14, 2012. The image on the left, STEREO-B, shows a dark vertical line slightly to the upper left of center. Only by looking at the image on the right, captured by STEREO-A from a different direction, is this feature revealed to be a giant prominence of solar material bursting through the sun's atmosphere. Credit: NASA/STEREO.
View larger - View STEREO B larger - View STEREO A larger

On the evening of Oct. 25, 2006, the twin Solar Terrestrial Relations Observatory (STEREO) spacecraft launched into space, destined for fairly simple orbits: both circle the sun like Earth does, STEREO-A traveling in a slightly smaller and therefore faster orbit, STEREO-B traveling in a larger and slower orbit. Those simple orbits, however, result in interesting geometry. As one spacecraft gained an increasing lead over Earth, the other trailed further and further behind. In February of 2011, each STEREO spacecraft was situated on opposite sides of the sun, and on Sept. 1, 2012, the two spacecraft and and the Solar Dynamics Observatory (at Earth) formed an equal-sided triangle, with each observatory providing overlapping views of the entire sun.


Since its launch in 2006, the STEREO spacecraft have drifted further and further apart to gain different views of the sun. Credit: NASA/GSFC .  View larger
By providing such unique viewpoints, STEREO has offered scientists the ability to see all sides of the sun simultaneously for the first time in history, augmented with a view from Earth's perspective by NASA's Solar Dynamics Observatory (SDO). In addition to giving researchers a view of active regions on the sun before they even come over the horizon, combining two views is crucial for three-dimensional observations of the giant filaments that dance off the sun's surface or the massive eruptions of solar material known as coronal mass ejections (CMEs). Examine the images below to see how a feature on the sun can look dramatically different from two perspectives.


This map of the full sun on Oct. 14, 2012, was created by images from,  in order from left to right, STEREO-A, STEREO-B and SDO. Credit: NASA/STEREO/SDO/GSFC . View larger


Karen C. Fox
NASA's Goddard Space Flight Center

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Thursday, September 20, 2012

NASA's Solar Fleet Peers Into Coronal Cavities

Scientists want to understand what causes giant explosions in the sun's atmosphere, the corona, such as this one. The eruptions are called coronal mass ejections or CMEs and they can travel toward Earth to disrupt human technologies in space. To better understand the forces at work, a team of researchers used NASA data to study a precursor of CMEs called coronal cavities. Credit: NASA/Solar Dynamics Observatory (SDO) . View Larger

The sun's atmosphere dances. Giant columns of solar material – made of gas so hot that many of the electrons have been scorched off the atoms, turning it into a form of magnetized matter we call plasma – leap off the sun's surface, jumping and twisting. Sometimes these prominences of solar material, shoot off, escaping completely into space, other times they fall back down under their own weight. 

The prominences are sometimes also the inner structure of a larger formation, appearing from the side almost as the filament inside a large light bulb. The bright structure around and above that light bulb is called a streamer, and the inside "empty" area is called a coronal prominence cavity. 

 Such structures are but one of many that the roiling magnetic fields and million-degree plasma create in the sun's atmosphere, the corona, but they are an important one as they can be the starting point of what's called a coronal mass ejection, or CME. CMEs are billion-ton clouds of material from the sun’s atmosphere that erupt out into the solar system and can interfere with satellites and radio communications near Earth when they head our way.

 "We don't really know what gets these CMEs going," says Terry Kucera, a solar scientist at NASA's Goddard Space Flight Center in Greenbelt, Md. "So we want to understand their structure before they even erupt, because then we might have a better clue about why it's erupting and perhaps even get some advance warning on when they will erupt."

 Kucera and her colleagues have published a paper in the Sept. 20, 2012, issue of The Astrophysical Journal on the temperatures of the coronal cavities. This is the third in a series of papers -- the first discussed cavity geometry and the second its density -- collating and analyzing as much data as possible from a cavity that appeared over the upper left horizon of the sun on Aug. 9, 2007 (below). By understanding these three aspects of the cavities, that is the shape, density and temperature, scientists can better understand the space weather that can disrupt technologies near Earth. 

 The faint oval hovering above the upper left limb of the sun in this picture is known as a coronal cavity. NASA’s Solar and Terrestrial Relations Observatory (STEREO) captured this image on Aug. 9, 2007. A team of scientists extensively studied this particular cavity in order to understand more about the structure and magnetic fields in the sun's atmosphere. Credit: NASA/STEREO. View Larger

 The Aug. 9 cavity lay at a fortuitous angle that maximized observations of the cavity itself, as opposed to the prominence at its base or the surrounding plasma. Together the papers describe a cavity in the shape of a croissant, with a giant inner tube of looping magnetic fields -- think something like a slinky -- helping to define its shape. The cavity appears to be 30% less dense than the streamer surrounding it, and the temperatures vary greatly throughout the cavity, but on average range from 1.4 million to 1.7 million Celsius (2.5 to 3 million Fahrenheit), increasing with height.

 Trying to describe a cavity, a space that appears empty from our viewpoint, from 93 million miles away is naturally a tricky business. "Our first objective was to completely pin down the morphology," says Sarah Gibson, a solar scientist at the High Altitude Observatory at the National Center for Atmospheric Research (NCAR) in Boulder, Colo. who was an author on all three cavity papers. "When you see such a crisp clean shape like this, it’s not an accident. That shape is telling you something about the physics of the magnetic fields creating it, and understanding those magnetic fields can also help us understand what’s at the heart of CMEs."

 To do this, the team collected as much data from as many instruments from as many perspectives as they could, including observations from NASA’s Solar Terrestrial Relations Observatory (STEREO), ESA and NASA’s Solar and Heliospheric Observatory (SOHO), the JAXA/NASA mission Hinode, and NCAR's Mauna Loa Solar Observatory.

 They collected this information for the cavity’s entire trip across the face of the sun along with the sun’s rotation. Figuring out, for example, why the cavity was visible on the left side of the sun but couldn’t be seen as well on the right held important clues about the structure’s orientation, suggesting a tunnel shape that could be viewed head on from one perspective, but was misaligned for proper viewing from the other. The cavity itself looked like a tunnel in a crescent shape, not unlike a hollow croissant. Magnetic fields loop through the croissant in giant circles to support the shape, the way a slinky might look if it were narrower on the ends and tall in the middle – the entire thing draped in a sheath of thick plasma. The paper describing this three-dimensional morphology appeared in The Astrophysical Journal on Dec. 1, 2010.

 Next up, for the second paper, was the cavity’s density. Figuring out density and temperature was a trickier prospect since one’s point of view of the sun is inherently limited. Because the sun’s corona is partially transparent, it is difficult to tease out differences of density and temperature along one’s line of sight; all the radiation from a given line hits an instrument at the same time in a jumble, information from one area superimposed upon every other.

 Using a variety of techniques to tease density out from temperature, the team was able to determine that the cavity was 30% less than that of the surrounding streamer. This means that there is, in fact, quite a bit of material in the cavity. It simply appears dim to our eyes when compared with the denser, brighter areas nearby. The paper on the cavity’s density appeared in The Astrophysical Journal on May 20, 2011.

 "With the morphology and the density determined, we had found two of the main characteristics of the cavity, so next we focused on temperature," says Kucera. "And it turned out to be a much more complicated problem. We wanted to know if it was hotter or cooler than the surrounding material – the answer is that it is both."

 Ultimately, what Kucera and her colleagues found was that the temperature of the cavity was not – on average – hotter or cooler than the surrounding plasma.

 However, it was much more varied, with hotter and cooler areas that Kucera thinks link the much colder 10,000 degrees Celsius (17,000 F) prominence at the bottom to the million to two million degrees Celsius (1.8 million to 3.6 million degrees Fahrenheit) corona at the top. Other observations of cavities show that cavity features are constantly in motion creating a complicated flow pattern that the team would like to study further.

 While these three science papers focused on just the one cavity from 2007, the scientists have already begun comparing this test case to other cavities and find that the characteristics are fairly consistent. More recent cavities can also be studied using the high-resolution images from NASA’s Solar Dynamics Observatory (SDO), which launched in 2010.

 "Our point with all of these research projects into what might seem like side streets, is ultimately to figure out the physics of magnetic fields in the corona," says Gibson. "Sometimes these cavities can be stable for days and weeks, but then suddenly erupt into a CME. We want to understand how that happens. We’re accessing so much data, so it’s an exciting time – with all these observations, our understanding is coming together to form a consistent story."

Related Links - NASA's Solar Fleet

Karen C. Fox

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