NASA SDO - Coronal Loops Extraordinaire! LittleSDOHMI 2014-10-28 | Here is now a movie from October 26 covering about 50 hours. Look how this region continues to rotate towards the western limb of the Sun and at the same time also producing solar flares.What's really beautiful is the interaction of all the coronal loops. Coronal loops are found around sunspots and in active regions. These structures are associated with the closed magnetic field lines that connect magnetic regions on the solar surface. Many coronal loops last for days or weeks, but most change quite rapidly.Credit: NASA Solar Dynamics Observatory (Little SDO)
NASA SDO - Prodigious Sunspot LittleSDOHMI 2014-10-22 | The largest sunspot of this solar cycle has now rotated around so that it is just about facing Earth.The video clip of filtered light images (October 18-22, 2014) show this substantial active region is 125,000 km wide, almost as big as the planet Jupiter, and many times the size of Earth.The region appears to have the kind of unstable magnetic field that suggests it might well produce more solar storms. It has already blasted out three substantial flares and numerous smaller ones. Sunspots are darker, cooler regions of the Sun with intense magnetic fields poking out through the surface.Credit: NASA Solar Dynamics Observatory (Little SDO)
NASA SDO - Lunar Transit, September 24, 2014 LittleSDOHMI 2014-09-24 | On September 24, 2014 the Moon made a quick appearance and transited through my field of view. At approx. 06:48 UT the Moon entered from the bottom right and moved across to the upper left where it exited at approx. 07:21 UT. The Moon's crisp horizon can be seen up against the Sun, because the Moon does not have an atmosphere. (At other times of the year, like last week, when Earth blocks my view, the Earth's horizon looks fuzzy due to its atmosphere.)Credit: NASA Solar Dynamics Observatory (Little SDO)
NASA SDO - Filament Liftoff LittleSDOHMI 2014-09-05 | The long, dark solar filament that had been visible for many days finally lifted off and broke away into space (September 2, 2014). Filaments are elongated clouds of plasma tethered above the Sun’s surface by powerful magnetic forces. Filaments are notoriously unstable.They appear darker when viewed in extreme ultraviolet light because they are somewhat cooler than the underlying material. The video covers about 14 hours of activity.Credit: NASA Solar Dynamics Observatory (Little SDO)
NASA SDO - Fall Earth Eclipse Season Starts (Aug 29, 2014) LittleSDOHMI 2014-08-29 | Twice a year, around March and around September, I get to see Earth moving in between my telescopes and the Sun. Everyday for the next three weeks Earth will eclipse the Sun. The eclipses are fairly short near the beginning and end of the season but ramp up to 72 minutes in the middle. Any spacecraft observing the Sun from an orbit around Earth has to contend with such eclipses, but my orbit is designed to minimize them as much as possible, as they block observations of the Sun.In the video one can see how the boundaries of the shadow of Earth on the Sun are not perfectly sharp since my telescopes can see some light from the brighter parts of the Sun coming through Earth's atmosphere.The August 29, 2014 eclipse only lasted a little over 4 minutes. Credit: NASA Solar Dynamics Observatory (Little SDO)
NASA SDO - Amazing Filament LittleSDOHMI 2014-08-07 | The Sun sported a very long filament (over 30 times the size of Earth) that angled diagonally across its surface for over a week (July 31 – Aug. 6, 2014). Filaments are clouds of cooler gas suspended above the Sun’s surface by magnetic forces. They are notoriously unstable and often break apart in just hours or days. So far, this one has held together as it rotated along with the Sun for over a week. The images were taken in the 193 Angstrom wavelength of extreme ultraviolet light and were tinted red instead of its usual brown hue. Credit: NASA SDO
NASA - Carrington-class CME Narrowly Misses Earth LittleSDOHMI 2014-07-31 | The close shave happened almost two years ago. On July 23, 2012, a plasma cloud or "CME" rocketed away from the Sun as fast as 3000 km/s, more than four times faster than a typical eruption. The storm tore through Earth orbit, but fortunately Earth wasn't there. Instead it hit the STEREO-A spacecraft. Researchers have been analyzing the data ever since, and they have concluded that the storm was one of the strongest in recorded history.1st SEGMENTWhile I did not have a direct view of the region which launched the large coronal mass ejection (CME) of July 23, 2012, it still managed to catch a glimpse of the solar plasma as it launched into space. The eruption becomes visible at timestamp 02:14:24 UTC in the lower right side of the movies below.2nd & 3r SEGMENTSTEREO-A, at a position along Earth's orbit where it has an unobstructed view of the far side of the Sun, could clearly observe possibly the most powerful coronal mass ejection (CME) of solar cyle 24 on July 23, 2012. The visualizations on this page cover the entire day.We see the flare erupt in the lower right quadrant of the solar disk from a large active region. The material is launched into space in a direction towards STEREO-A. This creates the ring-like 'halo' CME visible in the STEREO-A coronagraph, COR-2 (blue circular image).As the CME expands beyond the field of view of the COR-2 imager, the high energy particles reach STEREO-A, creating the snow-like noise in the image. The particles also strike the HI-2 imager (blue square) brightening the image.4th SEGMENTLike me, Little SDO, STEREO-B did not have a direct view of the coronal mass ejection (CME) launched by the Sun on July 23, 2012. However, the active region involved was very close to the limb of the sun (lower left quadrant) and STEREO-B provided an excellent view of plasma launched in both ultraviolet light and the white-light coronagraph5th & 6th SEGMENTIn the last visualizations, generated from the Enlil space weather model, green represents particle density, usually protons and other ions. In green, we see the Parker spiral moving out from the Sun generated by the Sun's current sheetRed represents particles at high temperatures and shows the CME is hotter than the usual solar wind flow. Large changes in density are represented in blue. These three colors sometimes combine to tell us more about the characteristics of the event (noted in the 3-color Venn diagram below).Since this was a large and potentially disruptive event, the obvious question is why it didn't damage STEREO-A. The reason is that as this cloud of charged particles move through space, they alter magnetic fields which can induce electric voltages in electrical conductors. The intensity of these voltages are proportional to the size of the electrical conducting path. The STEREO-A spacecraft is small enough that the induced voltages are small and the spacecraft is designed to withstand them.However, if this CME had struck Earth's magnetosphere, which has a much stronger magnetic field, the changing magnetic field would induce much larger voltages in systems with long electrical conductors, such as power lines that run over long distances. These significantly higher voltages can damage power transformers.Credit: NASA Solar Dynamics Observatory (Little SDO), NASA STEREO, Dusan Odstrcil (GMU), Leila Mays (CUA) and Janet Luhmann (UCB) and NASA's Scientific Visualization Studio.
NASA SDO - Graceful Turbulence LittleSDOHMI 2014-03-27 | Powerful magnetic forces above an active region spun and pulled at a blob of plasma until it lost its connections and blew out into space on March 26, 2014.The resultant swirling presents its own kind of graceful, almost ballet-like bends and sweeps. To offer some kind of size perspective that blob before it breaks away was easily larger than several Earths.The event was observed in extreme ultraviolet light over about 5.5 hours between 7:00 and 12:20 UT.Credit: NASA Solar Dynamics Observatory (Little SDO)
NASA SDO - Channel Eruption LittleSDOHMI 2014-02-20 | When a solar filament above the Sun's surface (the darker, slanted line seen before the eruption)) became unstable and erupted, it briefly left an empty channel that was almost immediately followed by a series magnetic loops reconnecting (on February 18, 2014) over the channel. The action was caught in this combination of two wavelengths of extreme ultraviolet light (AIA 171 and AIA 304). This kind of channel eruption is not rare, but not usually observed so clearly. Credit: NASA SDO
NASA SDO - Year 4 LittleSDOHMI 2014-02-11 | The Sun is always changing and NASA's Solar Dynamics Observatory is always watching. Launched on February 11, 2010, SDO keeps a 24-hour eye on the entire disk of the Sun, with a prime view of the graceful dance of solar material coursing through the Sun's atmosphere, the corona. SDO's fourth year in orbit was no exception: NASA is releasing a movie of some of SDO's best sightings of the year, including massive solar explosions and giant sunspot shows.SDO captures images of the Sun in 10 different wavelengths, each of which helps highlight a different temperature of solar material. Different temperatures can, in turn, show specific structures on the Sun such as solar flares, which are giant explosions of light and x-rays, or coronal loops, which are streams of solar material traveling up and down looping magnetic field lines. The movie shows examples of both, as well as what's called prominence eruptions, when masses of solar material leap off the sun. The movie also shows a giant sunspot group on the solar surface. This sunspot, a magnetically strong and complex region appearing in mid-January 2014, was one of the largest in nine years.The movie runs 3 minutes and 44 seconds and it was created at NASA Goddard Space Flight Center in Greenbelt, Md.Scientists study these images to better understand the complex electromagnetic system causing the constant movement on the sun, which can ultimately have an effect closer to Earth, too: Flares and another type of solar explosion called coronal mass ejections can sometimes disrupt technology in space. Moreover, studying our closest star is one way of learning about other stars in the galaxy.Credit: NASA Solar Dynamics Observatory
NASA SDO - Lunar Transit & Solar Flare LittleSDOHMI 2014-01-30 | On January 30, 2014, beginning at 8:31 a.m EST, the moon moved between the Sun and me, giving the me 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.Right at the end of the Lunar Transit the Sun emitted a mid-level solar flare, peaking at 11:11 a.m. EST. Credit: NASA Solar Dynamics ObservatoryMusic: Karl Engel - The Flames of Rom
NASA SDO - Argos View LittleSDOHMI 2013-12-17 | Argos (or Argus Panoptes) was the 100-eyed giant in Greek mythology.While NASA Solar Dynamics Observatory (SDO) has significantly less than 100 eyes, seeing connections in the solar atmosphere through the many filters of SDO presents a number of interesting challenges. This visualization experiment illustrates a mechanism for highlighting these connections.The wavelengths presented are: 617.3nm optical light from SDO/HMI. From SDO/AIA we have 170nm (pink), then 160nm (green), 33.5nm (blue), 30.4nm (orange), 21.1nm (violet), 19.3nm (bronze), 17.1nm (gold), 13.1nm (aqua) and 9.4nm (green).We've locked the camera to rotate the view of the Sun so each wedge-shaped wavelength filter passes over a region of the Sun. As the features pass from one wavelength to the next, we can see dramatic differences in solar structures that appear in different wavelengths.- Filaments extending off the limb of the Sun which are bright in 30.4 nanometers, appear dark in many other wavelengths.- Sunspots which appear dark in optical wavelengths, are festooned with glowing ribbons in ultraviolet wavelengths.- Small flares, invisible in optical wavelengths, are bright ribbons in ultraviolet wavelengths.- If we compare the visible light limb of the Sun with the 170 nanometer filter on the left, with the visible light limb and the 9.4 nanometer filter on the right, we see that the 'edge' is at different heights. This effect is due to the different amounts of absorption, and emission, of the solar atmosphere in ultraviolet light.- In far ultraviolet light, the photosphere is dark since the black-body spectrum at a temperature of 5700 Kelvin emits very little light in this wavelength.The movie opens with a full-disk view of the Sun in visible wavelengths. Then the filters are applied to small pie-shaped wedges of the Sun, starting with 170nm (pink), then 170nm (green), 33.5nm (blue), 30.4nm (orange), 21.1nm (violet), 19.3nm (bronze), 17.1nm (gold), 13.1nm (aqua) and 9.4nm (green). We let the set of filters sweep around the solar disk and then zoom and rotate the camera to rotate with the filters as the solar image is rotate underneath. Credit: NASA Solar Dynamics Observatory
NASA Sun Magnetic Flip LittleSDOHMI 2013-12-06 | This visualization shows the position of the Sun's magnetic fields from January 1997 to December 2013. The field lines swarm with activity: The magenta lines show where the Sun's overall field is negative and the green lines show where it is positive. A region with more electrons is negative, the region with less is labeled positive. Additional gray lines represent areas of local magnetic variation.The entire Sun's magnetic polarity, flips approximately every 11 years -- though sometimes it takes quite a bit longer -- and defines what's known as the solar cycle. The visualization shows how in 1997, the Sun shows the positive polarity on the top, and the negative polarity on the bottom. Over the next 12 years, each set of lines is seen to creep toward the opposite pole eventually showing a complete flip. By the end of the movie, each set of lines are working their way back to show a positive polarity on the top to complete the full 22 year magnetic solar cycle.At the height of each magnetic flip, theSun goes through periods of more solar activity, during which there are more sunspots, and more eruptive events such as solar flares and coronal mass ejections, or CMEs. The point in time with the most sunspots is called solar maximum.Credit: NASA
NASA/ESA SOHO - Has Comet ISON Broken Up? LittleSDOHMI 2013-11-27 | Has Comet ISON broken up? It is still unclear.As Comet ISON heads toward its closest approach to the Sun — known as perihelion — on Nov. 28, 2013, scientists have been watching through many observatories to see if the comet has already broken up under the intense heat and gravitational forces of the Sun. The comet is too far away to discern how many pieces it is in, so instead researchers carefully measure how bright it is, which can be used to infer its current state. Less light can sometimes mean that more of the material has boiled off and disappeared, perhaps pointing to a disintegrated comet. But also a disintegrating comet sometimes gives off more light, at least temporarily, so researchers look at the comet's pattern of behavior over the previous few days to work out what it may be doing.At times observations have suggested ISON was getting dimmer and might already be in pieces. However, over Nov. 26-27, 2013, the comet once again brightened. In the early hours of Nov. 27, the comet appeared in the view of the European Space Agency/NASA mission the Solar and Heliospheric Observatory in the Large Angle and Spectrometric Coronagraph instrument.Coronagraphs block out the bright light of the Sun in order to better see the dimmer solar atmosphere, the corona. In these images, the comet looks quite bright as it moves in from the lower right of the image. A giant cloud of solar material, called a coronal mass ejection or CME, is also seen in the images bursting off the bottom of the sun and heading out into space. It is as yet unclear if the CME is heading towards ISON but even if it does, it poses no real danger to the comet.If the comet has already broken up, it should disintegrate completely as it makes its slingshot around the Sun. This would provide a great opportunity for scientists to see the insides of the comet, and better understand its composition — as such information holds clues about what material was present during the solar system's formation when this comet was born. However, it would likely mean no comet visible in the night sky in December. We'll only know for sure after the comet rounds the Sun on Thanksgiving Day.Credit: NASA/ESA SOHO
NASA - What is a Sungrazing Comet? LittleSDOHMI 2013-11-22 | Sungrazing comets are a special class of comets that come very close to the Sun at their nearest approach, a point called perihelion. To be considered a sungrazer, a comet needs to get within about 850,000 miles from the Sun at perihelion. Many come even closer, even to within a few thousand miles.Being so close to the Sun is very hard on comets for many reasons. They are subjected to a lot of solar radiation which boils off their water or other volatiles. The physical push of the radiation and the solar wind also helps form the tails. And as they get closer to the Sun, the comets experience extremely strong tidal forces, or gravitational stress. In this hostile environment, many sungrazers do not survive their trip around the Sun. Although they don't actually crash into the solar surface, the sun is able to destroy them anyway.Many sungrazing comets follow a similar orbit, called the Kreutz Path, and collectively belong to a population called the Kreutz Group. In fact, close to 85% of the sungrazers seen by the SOHO satellite are on this orbital highway. Scientists think one extremely large sungrazing comet broke up hundreds, or even thousands, of years ago, and the current comets on the Kreutz Path are the leftover fragments of it. As clumps of remnants make their way back around the Sun, we experience a sharp increase in sungrazing comets, which appears to be going on now. Comet Lovejoy, which reached perihelion on December 15, 2011 is the best known recent Kreutz-group sungrazer. And so far, it is the only one that NASA's solar-observing fleet has seen survive its trip around the Sun.Comet ISON, an upcoming sungrazer with a perihelion of 730,000 miles on November 28, 2013, is not on the Kreutz Path. In fact, ISON's orbit suggests that it may gain enough momentum to escape the solar system entirely, and never return. Before it does so, it will pass within about 40 million miles from Earth on December 26th. Assuming it survives its trip around the Sun.Credit: NASA
NASA - How to Cook a Comet LittleSDOHMI 2013-11-21 | A comet's journey through the solar syste is perilous and violent. Before it reaches Mars - at some 230 million miles away from the Sun - the radiation of the Sun begins to cook off the frozen water ice directly into gas. This is called sublimation. It is the first step toward breaking the comet apart. If it survives this, the intense radiation and pressure closer to the sun could destroy it altogether.Animators at NASA Goddard Space Flight Center in Greenbelt, Md. created this short movie showing how the Sun can cook a comet.Such a journey is currently being made by Comet ISON. It began its trip from the Oort cloud region of our solar system and is now travelling toward the Sun. The comet will reach its closest approach to the sun on Thanksgiving Day -- Nov. 28, 2013 -- skimming just 730,000 miles above the Sun's surface. If it comes around the Sun without breaking up, the comet will be visible in the Northern Hemisphere with the naked eye, and from what we see now, ISON is predicted to be a particularly bright and beautiful comet.Even if the comet does not survive, tracking its journey will help scientists understand what the comet is made of, how it reacts to its environment, and what this explains about the origins of the solar system. Closer to the Sun, watching how the comet and its tail interact with the vast solar atmosphere can teach scientists more about the Sun itself. Credit: NASA Goddard
NASA SDO - ISON Observation LittleSDOHMI 2013-11-20 | We will point SDO at three different positions as Comet ISON moves through perihelion on November 28, 2013. This will let us look for the tail of the comet in our images. This movie shows you how we will point SDO. The clock in the lower left corner shows approximate UTC as a decimal.Credit: NASA SDO
NASA SDO - Double Barrel Action LittleSDOHMI 2013-11-14 | Two active regions rotating into view demonstrated quite clearly that they were ready for action (November 11-13, 2013). The regions, viewed in a wavelength of extreme ultraviolet light, were spurting and flaring in a rapid-fire style as their tangled magnetic fields struggled against each other. Towards the end a prominence near the upper left erupted while a flare, seen as a white flash, burst from the leading region.Credit: NASA SDO
NASA - Dynamic Earth LittleSDOHMI 2013-09-20 | A giant explosion of magnetic energy from the Sun, called a coronal mass ejection, slams into and is deflected completely by the Earth's powerful magnetic field. The Sun also continually sends out streams of light and radiation energy. Earth's atmosphere acts like a radiation shield, blocking quite a bit of this energy.Much of the radiation energy that makes it through is reflected back into space by clouds, ice and snow and the energy that remains helps to drive the Earth system, powering a remarkable planetary engine -- the climate. It becomes the energy that feeds swirling wind and ocean currents as cold air and surface waters move toward the equator and warm air and water moves toward the poles -- all in an attempt to equalize temperatures around the world.Credit: NASA/Goddard Space Flight Center
NASA SDO - Dynamics Loops LittleSDOHMI 2013-09-20 | Giant loops of plasma above the SunÕs surface are swaying back and forth, spanning distances up to an estimated 100,000 miles (September 18-19, 2013).The video clip covers a little over a day of activity viewed in extreme ultraviolet light. The loops actually are charged particles spiraling along numerous groups of magnetic field lines extending above active regions.Meanwhile, a darker, cooler mass of plasma swirled and twisted above the Sun in the upper left area of the frames. Credit: NASA Solar Dynamics Observatory
NASA SDO - Flitting Plasma LittleSDOHMI 2013-08-29 | While coiled loops of plasma swayed and waved in profile above the Sun's surface, a blob of darker (i.e., cooler) plasma rose up, twisted and turned, then finally split part along a roller-coaster path (August 27-28, 2013). In the meantime, the active region in the foreground put on an impressive show of its own with loops and flashes as magnetic forces struggled with each other. The video clip, which covered about 36 hours, was taken in extreme ultraviolet light. Credit: NASA Solar Dynamics Observatory
NASA SDO - Mission Untangles Motion Inside the Sun LittleSDOHMI 2013-08-29 | Helioseismic observations from my HMI (Helioseismic and Magnetic Imager) instrument revealed that meridional circulation in the solar interior has a double-cell structure with an equatorward flow located in the middle of the convection zone about 60,000 miles beneath the visible surface of the Sun. Meridional circulation, which transports solar materials between low and high latitudes inside the Sun, is a fundamental property of the Sun, but was poorly known. It is widely believed that the circulation plays an important role in redistributing solar angular momentum and transporting magnetic flux, setting up 11-year solar activity cycles. Previously it was thought that the circulation had a single-cell structure with a poleward flow near the surface and an equatorward flow located near the bottom of the convection zone.Through analyzing the unprecedented high-quality helioseismic data obtained fromHMI by using a helioseismic analysis technique called time-distance helioseismology, the solar physicists found that the solar meridional currents have at least two circulation cells in each hemisphere, with an equatorward flow located between about 40,000 and 80,000 miles below the surface. That is, the equatorward flow is roughly in the middle of the convection zone. This result provides a new insight into the dynamics of the solar interior hidden from direct observations, and requires a reexamination of the theories of solar magnetic cycles.Credit: NASA SDO / Stanford HMI
NASA SDO Lunar Transit, August 6, 2013 LittleSDOHMI 2013-08-07 | For almost 1 1/2 hours the Moon made an appearance in NASA's Solar Dynamics Observatory's view on August 6, 2013. While this was not a first, it is always fascinating to see these Lunar Transits. If you watch it closely, one can actually see the rigged area of the Moon. The Moon itself looks much bigger than the Sun - which is understandable as the Moon is many times closer to Earth (and to SDO) than the Sun is. Enjoy!Credit: NASA SDO
NASA SDO & NASA IRIS - A Comparison LittleSDOHMI 2013-07-26 | This video compares the Solar Dynamics Observatory's (SDO) resolution with the Interface Region Imaging Spectrograph (IRIS) resolution for the same region of the Sun.Credit: NASA SDO, NASA IRIS
NASA SDO - Traveling Sunspot Group; July 3 - 11, 2013 LittleSDOHMI 2013-07-12 | Tracking one of the largest sunspot groups across the Earth facing solar disk. This movie covers almost 9 days, from July 3 through almost the entire day of July 11, 2013. Galileo was the first to study dark spots on the Sun which we call "sunspots". They typically measure about 10,000 kilometers across, which makes them on the order of the size of the Earth. They often occur in groups, and come and go. At some times the Sun has hundreds of sunspots, while at other times it may have almost none. Individual spots may last from 1 to 100 days. A large group of spots typically lasts 50 days.As magnetic fields on the Sun rearrange and realign, dark spots known as sunspots can appear on its surface. Temperatures in the dark centers of sunspots drop to about 3700 K (compared to 5700 K for the surrounding photosphere).They typically last for several days, although very large ones may live for several weeks. Sunspots are magnetic regions on the Sun with magnetic field strengths thousands of times stronger than the Earth's magnetic field. Sunspots usually come in groups with two sets of spots. One set will have positive or north magnetic field while the other set will have negative or south magnetic field. The field is strongest in the darker parts of the sunspots - the umbra. The field is weaker and more horizontal in the lighter part - the penumbra.Credit: NASA SDO
NASA SDO - X-Class Solar Flares; A closer Look (May 13-15, 2013) LittleSDOHMI 2013-05-15 | A more intimate look at the recent X-class solar flares, including a look at the Active Region 1748, which has been producing these flares. My favorite segment is the yellow 171 angstrom wavelength. It shows the magnetic field lines in this area of the Sun's atmosphere, the corona, and how they began to twist and kink, generating the hottest solar material -- a charged gas called plasma. Enjoy this beautiful view of our Star. Credit: NASA Solar Dynamics Observatory
NASA SDO & NASA SOHO - Three X-class Solar Flares seen by Two Spacecrafts LittleSDOHMI 2013-05-14 | A look at the three X-class solar flares through two different instruments on two different spacecrafts. The "green" Sun is seen through the AIA instrument at 131 angstroms. This channel sees very hot temperatures, at approx. 18 million F, and is great to study solar flares. The "red" view is from NASA/ESA's LASCO C2 instrument and shows us the outer region and how the ejected plasma (called a Coronal Mass Ejection or CME) is traveling away from the Sun. As you can see these three flares occurred to the left of the Sun and the CME is not traveling towards Earth. No planets are in the way of this fast traveling CME. However, the CMEs appear to be on course to hit NASA's Epoxi and Spitzer spacecrafts on May 15-16.Credit: NASA SDO / NASA/ESA SOHO
NASA SDO - Three X-class Solar Flares in 24 Hours (May 13-14, 2013) LittleSDOHMI 2013-05-14 | Not everyday do we get to see three X-class solar flares in less than 24 hours. And because we have never been able to observe the Sun with so many sophisticated instruments, we love sharing the various views. This is seen through the AIA 304 angstroms wavelength. This channel sees the chromosphere and lower transition region of the Sun in extreme ultraviolet. The temperatures seen here are approx. 90,000 F.It starts off with the X1.7 flare, then the X2.8 and ends with the X3.2-class solar flare. Credit: NASA SDO
NASA SDO - Three Years with Narration by Dr. Alex Young LittleSDOHMI 2013-05-10 | This version of SDO: Three Years in Three Minutes is extended and narrated by NASA's Goddard Space Flight Center heliophysicist Alex Young. He highlights many interesting aspects of the video and points out several of the single-frame events that appear in it.In the three years since it first provided images of the sun in the spring of 2010, NASA's Solar Dynamics Observatory (SDO) 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. Each image is displayed for two frames at a 29.97 frame rate.SDO's Atmospheric Imaging Assembly (AIA) 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 Kelvin. 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 the Earth at 6,876 miles per hour and the Earth orbits the Sun at 67,062 miles per hour.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.The four wavelength view at the end of the video shows light at 4500 Angstroms, which is basically the visible light view of the Sun, and reveals sunspots; light at 193 Angstroms which highlights material at 1 million Kelvin and reveals more of the Sun's corona; light at 304 Angstroms which highlights material at around 50,000 Kelvin and shows features in the transition region and chromosphere of the Sun; and light at 171 Angstroms.Noteworthy events that appear briefly in the main sequence of this video:00:30;24 Partial eclipse by the moon00:31;16 Roll maneuver01:11;02 August 9, 2011 X6.9 Flare, currently the largest of this solar cycle01:28;07 Comet Lovejoy, December 15, 201101:42;29 Roll Maneuver01:51;07 Transit of Venus, June 5, 201202:28;13 Partial eclipse by the moonCredit: NASA SDO
NASA - NASAs Heliophysics Fleet Captures May 1, 2013 Prominence Eruption and CME LittleSDOHMI 2013-05-07 | On May 1, 2013, NASA's Solar Dynamics Observatory (SDO) watched as an active region just around the left edge of the Sun erupted with a huge cloud of solar material--a heated, charged gas called plasma. This eruption, called a coronal mass ejection, or CME, flung the plasma out through the solar system. Viewing the Sun in the extreme ultraviolet wavelength of 304 angstroms, SDO provided a beautiful view of the initial arc as it left the solar surface.Such eruptions soon leave SDO's field of view, but other satellites in NASA's solar-observing fleet can pick them up, tracking such space weather to determine if they are headed toward Earth or spacecraft near other planets. With advance warning, many space assets can move into safe mode and protect themselves from the ill effects of such particle radiation.In addition to the images captured by SDO, the May 1, 2013 CME was also images by the ESA/NASA Solar and Heliospheric Observatory (SOHO). SOHO houses two overlapping coronagraphs--telescopes where the bright sun is blocked by a disk so it doesn't overpower the fainter solar atmosphere--and they both saw the CME continue outward. The LASCO C2 coronagraph shows the region out to about 2.5 million miles. The LASCO C3 coronagraph expands even farther out to around 13.5 million miles. Both of these instruments show the CME as it expands and becomes fainter on its trip away from the Sun.NASA's Solar Terrestrial Relations Observatory (STEREO) Ahead satellite saw the eruption from a very different angle. It, along with its twin STEREO Behind, is traveling around the Sun along a line very close to Earth's orbit, but not in sync with Earth. Currently, STEREO-A is more than a third of an orbit ahead of the Earth and has a view of the far side of the Sun. From this perspective, the CME came off the right side of the Sun. STEREO has an extreme ultraviolet camera similar to SDO's, but it also has coronagraphs like SOHO. As a result, it was able to track the CME from the solar surface out to 6.3 million miles.Working together, such missions provide excellent coverage of a wide variety of solar events, a wealth of scientific data--and lots of beautiful imagery.Credit: NASA SDO, STEREO, NASA & ESA SOHO
NASA SDO - Graceful Eruption, March 16, 2013 LittleSDOHMI 2013-03-22 | A solar prominence began to bow out and the broke apart in a graceful, floating style during a little less than four hours of March 16, 2013). The sequence was captured in extreme ultraviolet light. A large cloud of the particles appeared to hover further out above the surface before it faded away. Credit: NASA SDO
NASA SDO - Earth and Moon, March 11, 2013 LittleSDOHMI 2013-03-11 | This movie shows the March 11, 2013 Earth Eclipse and the Lunar Transit. On March 2, 2013, NASA's Solar Dynamics Observatory (SDO) entered its semiannual eclipse season, a period of three weeks when Earth blocks its view of the Sun for a period of time each day. On March 11, however, SDO was treated to two transits. Earth blocked SDO's view of the sun from about 2:15 to 3:45 a.m. EDT. Later in the same day, from around 7:30 to 8:45 a.m. EDT, the moon moved in front of the Sun for a partial eclipse.When Earth blocks the Sun, the boundaries of Earth's shadow appear fuzzy, since SDO can see some light from the sun coming through Earth's atmosphere. The line of Earth appears almost straight, since Earth -- from SDO's point of view -- is so large compared to the Sun.The eclipse caused by the moon looks far different. Since the moon has no atmosphere, its curved shape can be seen clearly, and the line of its shadow is crisp and clean. Any spacecraft observing the Sun from an orbit around Earth has to contend with such eclipses, but SDO's orbit is designed to minimize them as much as possible, with only two three-week eclipse seasons each year. The 2013 spring eclipse season continues until March 26. The fall season will begin on September 2.Credit: NASA SDO
NASA SDO - A Quiet Interlude in Solar Max LittleSDOHMI 2013-03-07 | Something unexpected is happening on the Sun. 2013 was supposed to be the year of "solar maximum," the peak of the 11-year sunspot cycle. Yet 2013 has arrived and solar activity is relatively low. Sunspot numbers are well below their values from 2011, and strong solar flares have been infrequent. The quiet has led some observers to wonder if forecasters missed the mark.Solar physicist Dean Pesnell of NASA's Goddard Space Flight Center has a different explanation. "This is solar maximum," he says. "But it looks different from what we expected because it is double-peaked."Conventional wisdom holds that solar activity swings back and forth like a simple pendulum. At one end of the cycle, there is a quiet time with few sunspots and flares. At the other end, solar max brings high sunspot numbers and frequent solar storms. It's a regular rhythm that repeats every 11 years.Reality is more complicated. Astronomers have been counting sunspots for centuries, and they have seen that the solar cycle is not perfectly regular. The back-and-forth swing in sunspot counts can take anywhere from 10 to 13 years to complete. Also, the amplitude of the cycle varies; some solar maxima are very weak, others very strong.Pesnell notes yet another complication in the solar cycle: "The last two solar maxima, around 1989 and 2001, had not one but two peaks." Solar activity went up, dipped, then rose again, performing a mini-cycle that lasted about two years. The same thing could be happening now, as sunspot counts jumped in 2011 and dipped in 2012. Pesnell expects them to rebound in 2013: "I am comfortable in saying that another peak will happen in 2013 and possibly last into 2014."Another curiosity of the solar cycle is that the Sun's hemispheres do not always peak at the same time. In the current cycle, the south has been lagging behind the north. The second peak, if it occurs, will likely feature the southern hemisphere playing catch-up, with a surge in activity south of the Sun's equator.Pesnell is a member of the NOAA/NASA Solar Cycle Prediction Panel, which last assembled in 2008 to forecast the next solar maximum. The panel declared: "The next solar cycle (Cycle 24) will be below average in intensity, with a maximum sunspot number of 90. Given the date of solar minimum and the predicted maximum intensity, solar maximum is now expected to occur in May 2013."Given the tepid state of solar activity now, a maximum in May seems unlikely. "We may be seeing what happens when you predict a single amplitude and the Sun responds with a double peak," says Pesnell. He notes a similarity between Solar Cycle 24 and Solar Cycle 14, which had a double-peak during the first decade of the 20th century. If the two cycles are twins, "it would mean one peak in late 2013 and another in 2015."Credit: NASA SDO
NASA SDO - Fiery Looping Rain on the Sun LittleSDOHMI 2013-02-20 | Eruptive events on the Sun can be wildly different. Some come just with a solar flare, some with an additional ejection of solar material called a coronal mass ejection (CME), and some with complex moving structures in association with changes in magnetic field lines that loop up into the Sun's atmosphere, the corona.On July 19, 2012, an eruption occurred on the sun that produced all three. A moderately powerful solar flare exploded on the Sun's lower right hand limb, sending out light and radiation. Next came a CME, which shot off to the right out into space. And then, the Sun treated viewers to one of its dazzling magnetic displays -- a phenomenon known as coronal rain.Over the course of the next day, hot plasma in the corona cooled and condensed along strong magnetic fields in the region. Magnetic fields, themselves, are invisible, but the charged plasma is forced to move along the lines, showing up brightly in the extreme ultraviolet wavelength of 304 Angstroms, which highlights material at a temperature of about 50,000 Kelvin. This plasma acts as a tracer, helping scientists watch the dance of magnetic fields on the Sun, outlining the fields as it slowly falls back to the solar surface.The footage in this video was collected by the Solar Dynamics Observatory's AIA instrument. SDO collected one frame every 12 seconds, and the movie plays at 30 frames per second, so each second in this video corresponds to 6 minutes of real time. The video covers 12:30 a.m. EDT to 10:00 p.m. EDT on July 19, 2012.Credit: NASA SDO Music: "Thunderbolt" by Lars Leonhard, courtesy of artist.
NASA SDO - Year 3 Review LittleSDOHMI 2013-02-12 | As NASA Solar Dynamics Observatory (Little SDO) has started Year 4, let's take a look back at Year 3. On February 11, 2010, NASA launched an unprecedented solar observatory into space. The 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.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.Credit: NASA SDO
NASA SDO - Making The Rounds, January 31, 2013 LittleSDOHMI 2013-02-01 | Early on January 31, 2013 I observed a visual phenomena that most of us do not recall ever seeing before: a ring-shaped prominence that lay flat above the Sun's surface. Plasma streaming along the magnetic field lines appears to go in both directions at the same time along the field lines. Before long, the prominence became unstable and erupted in a large swirl with most of the materials falling back intio the Sun. You never know what you are going to see next.Credit: NASA SDO
NASA SDO - SDO Provides First Sightings of How a Coronal Mass Ejection Forms LittleSDOHMI 2013-01-31 | On July 18, 2012, a fairly small explosion of light burst off the lower right limb of the sun. Such flares often come with an associated eruption of solar material, known as a coronal mass ejection or CME -- but this one did not. Something interesting did happen, however. Magnetic field lines in this area of the sun's atmosphere, the corona, began to twist and kink, generating the hottest solar material -- a charged gas called plasma -- to trace out the newly-formed slinky shape. The plasma glowed brightly in extreme ultraviolet images from the Atmospheric Imaging Assembly (AIA) aboard NASA's Solar Dynamics Observatory (SDO) and scientists were able to watch for the first time the very formation of something they had long theorized was at the heart of many eruptive events on the sun: a flux rope.Eight hours later, on July 19, the same region flared again. This time the flux rope's connection to the sun was severed, and the magnetic fields escaped into space, dragging billions of tons of solar material along for the ride -- a classic CME.More than just gorgeous to see, such direct observation offers one case study on how this crucial kernel at the heart of a CME forms. Such flux ropes have been seen in images of CMEs as they fly away from the sun, but it's never been known -- indeed, has been strongly debated -- whether the flux rope formed before or in conjunction with a CME's launch. This case shows a clear-cut example of the flux rope forming ahead of time.Credit: NASA SDO / NASA Goddard Space Flight Center
NASA SDO - Filament Eruption, January 31, 2013 LittleSDOHMI 2013-01-31 | A look at the filament break-up on January 31, 2013. The entire event lasted for approx. 4 hours. This video shows a variety of views of the break-up of this structure. Filaments are anchored to the Sun's surface in the photosphere, and extend outwards into the Sun's hot outer atmosphere, called the corona. A filament forms over timescales of about a day, and stable filaments may persist in the corona for several months, looping hundreds of thousands of miles into space. Some of the plasma was released into space but not all could escape the gravitational pull of the Sun. It's not surprising that plasma should fall back to the Sun. After all, the Sun's gravity is powerful. Credit: NASA SDO
NASA SDO - Dragon Tail Filament Eruption, January 31, 2013 LittleSDOHMI 2013-01-31 | A look at the filament break-up on January 31, 2013. The entire event lasted for approx. 4 hours. This video shows a variety of views of the break-up of this structure. Filaments are anchored to the Sun's surface in the photosphere, and extend outwards into the Sun's hot outer atmosphere, called the corona. A filament forms over timescales of about a day, and stable filaments may persist in the corona for several months, looping hundreds of thousands of miles into space. Some of the plasma was released into space but not all could escape the gravitational pull of the Sun. It's not surprising that plasma should fall back to the Sun. After all, the Sun's gravity is powerful. Credit: NASA SDO
NASA SDO - Roger! We Have a Liftoff (January 23, 2013) LittleSDOHMI 2013-01-23 | A solar prominence arched up and then erupted out from near the Sun's surface (January 23, 2013). Solar Dynamics Observatory observed the event in extreme ultraviolet light as it evolved over seven hours. The strand of solar plasma appeared to perform a somersault as it expanded and disappeared into space. The disruption to the magnetic fields in the area generated the coiling and spreading wave-like action below the site of the event. Solar prominences are unstable clouds of cooler gases suspended above the Sun's surface by magnetic forces.Credit: NASA SDO
NASA SDO - Tracking AR1654 (Jan 7 - 15, 2013) LittleSDOHMI 2013-01-15 | Active Region 1654 has traveled half across the Earth facing side of the Sun. This video tracks this region starting January 7 through January 15, 2013. Despite its big size, over 120,000 miles from end to end on January 12, this active region has only produced a couple of medium sized solar flares (M-class flares). However, it is a beautiful view to observe the changing shape of these sunspots. Sunspots are dark areas on the solar surface, contain strong magnetic fields that are constantly shifting. A moderate-sized sunspot is about as large as the Earth. Sunspots form and dissipate over periods of days or weeks. They occur when strong magnetic fields emerge through the solar surface and allow the area to cool slightly, from a background value of 6000 ° C down to about 4200 ° C; this area appears as a dark spot in contrast with the very bright photosphere of the Sun. The rotation of these sunspots can be seen on the solar surface; they take about 27 days to make a complete rotation as seen from Earth.Sunspots remain more or less in place on the Sun. Near the solar equator the surface rotates at a faster rate than near the solar poles. Groups of sunspots, especially those with complex magnetic field configurations, are often the sites of solar flares. Over the last 300 years, the average number of sunspots has regularly waxed and waned in an 11-year (on average) solar or sunspot cycle.The second segment of this movie shows the same period (January 7 through 15, 2013) but in Extreme Ultraviolet. This composite of three wavelengths (211, 193 and 171 angstroms) shows the crackling region coming over the Eastern limb of the Sun and then tracking across the center. Credit: NASA SDO
NASA SDO - Prominence Eruption on January 10, 2013 LittleSDOHMI 2013-01-11 | This segment shows a beautiful prominence eruption on January 10, 2013. A solar prominence (also known as a filament when viewed against the solar disk) is a large, bright feature extending outward from the Sun's surface. Prominences are anchored to the Sun's surface in the photosphere, and extend outwards into the Sun's hot outer atmosphere, called the corona. A prominence forms over timescales of about a day, and stable prominences may persist in the corona for several months, looping hundreds of thousands of miles into space. Scientists are still researching how and why prominences are formed.The red-glowing looped material is plasma, a hot gas comprised of electrically charged hydrogen and helium. The prominence plasma flows along a tangled and twisted structure of magnetic fields generated by the sun's internal dynamo. An erupting prominence occurs when such a structure becomes unstable and bursts outward, releasing the plasma.When a prominence erupts, the released material is part of a larger magnetic structure called Coronal Mass Ejections (CMEs). When directed toward Earth, CMEs can interact with our Earth's magnetic field and trigger a geomagnetic storm, with bright auroras and the potential for disturbance in communications and electrical power networks.This prominence eruption was not Earth directed. Credit: NASA SDO
NASA - Dynamic Earth LittleSDOHMI 2013-01-10 | A giant explosion of magnetic energy from the Sun, called a coronal mass ejection, slams into and is deflected completely by the Earth's powerful magnetic field. The Sun also continually sends out streams of light and radiation energy. Earth's atmosphere acts like a radiation shield, blocking quite a bit of this energy.Much of the radiation energy that makes it through is reflected back into space by clouds, ice and snow and the energy that remains helps to drive the Earth system, powering a remarkable planetary engine -- the climate. It becomes the energy that feeds swirling wind and ocean currents as cold air and surface waters move toward the equator and warm air and water moves toward the poles -- all in an attempt to equalize temperatures around the world.Credit: NASA / GSFC Visualization Center
NASA SDO - Its a Loopy Sun LittleSDOHMI 2013-01-08 | This video covers January 5 through 7 and shows the 171 angstroms channel, which is especially good at showing coronal loops - the arcs extending off of the Sun where plasma moves along the magnetic field lines. The brightest spots seen here are locations where the magnetic field near the surface is exceptionally strong. The characteristic temperature here is 1 million K (or 1.8 million F). Many of these loops could fit several Earths inside of them. Credit: NASA SDO
NASA SDO - Solar Ballet (Dec 31, 2012) LittleSDOHMI 2012-12-31 | A very nice display of solar activity - it's a New Year's Eve Ballet. This performance happened on December 31, 2012 and this segment covers 4 hours in real time. Happy 2013!
NASA SDO - Sungrazing Comets as Solar Probes LittleSDOHMI 2012-12-07 | To observe how winds move high in Earth's atmosphere, scientists sometimes release clouds of barium as tracers to track how the material corkscrews and sweeps around -- but scientists have no similar technique to study the turbulent atmosphere of the Sun. So researchers were excited in December 2011, when Comet Lovejoy swept right through the sun's corona with its long tail streaming behind it. NASA's Solar Dynamics Observatory (SDO) captured images of the comet, showing how its long tail was buffeted by systems around the Sun, offering scientists a unique way of observing movement as if they'd orchestrated the experiment themselves. Since comet tails have ionized gases, they are also affected by the Sun's magnetic field, and can act as tracers of the complex magnetic system higher up in the atmosphere. Comets can also aid in the study of coronal mass ejections and the solar wind.Credit: NASA SDO
NASA - Why Are We Seeing So Many Sungrazing Comets? LittleSDOHMI 2012-12-07 | Before 1979, there were less than a dozen known sungrazing comets. As of December 2012, we know of 2,500. Why did this number increase? With solar observatories like SOHO, STEREO, and SDO, we have not only better means of viewing the sun, but also the comets that approach it. SOHO allows us to see smaller, fainter comets closer to the sun than we have ever been able to see before. Even though many of these comets do not survive their journey past the sun, they survive long enough to be observed, and be added to our record of sungrazing comets.NASA SDO & STEREO, NASA/ESA SOHO
NASA SDO - HMIs view of Active Region 1618 LittleSDOHMI 2012-11-23 | Solar active region 1618, tracked from 15 Nov to 22 Nov 2012. Seen in Magnetic field from SDO/HMI.
NASA SDO - AIAs view of Active Region 1618 in 171 A LittleSDOHMI 2012-11-23 | Solar active region 1618, tracked from 15 Nov to 22 Nov 2012. Seen in AIA 171. Scaled to match HMI movies of same region.
NASA SDO - HMIs view of Active Region 1618 - Continuum Near 6173 A LittleSDOHMI 2012-11-23 | Solar active region 1618, tracked from 15 Nov to 22 Nov 2012. Seen in continuum near 6173 A with limb darkening removed.
