The most detailed sunspot ever obtained in visible light was seen by new telescope at NJIT's Big Bear Solar Observatory. Credit: Big Bear Solar Observatory
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A new type of adaptive optics for solar observations has produced some incredible results, providing the most detailed image of a sunspot ever obtained in visible light. A new telescope built by the New Jersey Institute of Technology’s Big Bear Solar Observatory has seen its ‘first light’ using a deformable mirror, which is able to reduce atmospheric distortions. This is the first facility-class solar observatory built in more than a generation in the U.S.
The New Solar Telescope (NST) is located in the mountains east of Los Angeles. It has 97 actuators that make up the deformable mirror. By the summer of 2011, in collaboration with the National Solar Observatory, BBSO will have upgraded the current adaptive optics system to one utilizing a 349 actuator deformable mirror. The telescope has a 1.6 m clear aperture, with a resolution covering about 50 miles on the Sun’s surface.
The NST will be the pathfinder for an even larger ground-based telescope, the Advanced Technology Solar Telescope to be built over the next decade. Philip R. Goode from NJIT is leading a partnership with the National Solar Observatory (NSO) to develop a new and more sophisticated kind of adaptive optics, known as multi-conjugate adaptive optics. This new optical system will allow the researchers to increase the distortion-free field of view to allow for better ways to study these larger and puzzling areas of the Sun, and a 4-meter aperture telescope will be built in the next decade.
A plot of the STEREO data from August 14, 2010, showing the location of the planets and the direction of a CME from the Sun.
Update: Well, it turns out that while it looks like Venus and Mercury are getting pummeled by Coronal Mass Ejections, the geometry might not work out, at least not for every day that is included in the video above. UT reader Steven Janowiecki brought it to my attention that just because Mercury and Venus look close to the Sun doesn’t mean they’re actually in the line of fire, as they could be well behind or in front of the solar storm. I checked with STEREO project scientist Dr. Joseph Gurman, who took a look at the data. He put together a plot for August 14, (see below) and said, “It shows that Mercury and Venus are well to the East (left) of the Sun-earth line. The large CME on the 14th originated from an active region near the west limb of the Sun, and since most CME’s are about 60 degrees of heliolongitude in width on average, it’s unlikely that that event actually passed by Mercury or Venus.” There was one large event, however, on August 7, that appeared likely to be headed in the direction of Mercury and Venus.
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So, as it happens sometimes in astronomy, things are not always as they appear, and this exemplifies the challenges of estimating distance in astronomy.
Here’s the rest of the article as it ran originally:
Take a look at these Coronal Mass Ejections (CME) from the first part of August 2010, as seen by the two STEREO spacecraft. Here on Earth, we’ve had some aurorae, a result of the recent solar activity. But this STEREO imagery shows Venus and Mercury were blasted by these CMEs.
STEREO consists of two spacecraft – one ahead of Earth in its orbit, the other trailing behind. With this new pair of viewpoints, scientists are able to see the structure and evolution of solar storms as they blast from the Sun and move out through space.
These movies were taken by SECCHI, a suite of remote sensing instruments on both spacecraft consisting of two white light coronagraphs that make up the Sun Centered Imaging Package (SCIP), as well as a Heliospheric Imager (HI).
SECCHI can follow three-dimensional Coronal Mass Ejections (CMEs) from the Sun’s surface, through the corona and interplanetary medium, to impact at Earth. With these instruments, scientists are getting breakthroughs in understanding the origin and consequences of CMEs, in determining their three-dimensional structure, and more, and perhaps be able to predict space weather. Combining STEREO with the new Solar Dynamics Observatory, we’ll be learning more and more about the Sun in the next few years.
As an example of SDO’s capabilities, here’s an SDO image from earlier today showing the Sun’s limb.
View of the Sun from August 18, 2010 from the Solar Dynamics Observatory. Credit: NASA/SDO
Five sunspots appeared on the Sun on August 11, 2010. Image from SolarCycle24.com
Here’s something we’ve not seen in a long while: five sunspots on the Sun at once. Is the Sun finally waking up from its unusually long and deep solar minimum slumber? While activity on the Sun usually ebbs and flows on a fairly predictable 11-year cycle, this current cycle has been anything but conventional. In 2009, there were 260 days (71% of the time) that the Sun was ‘spotless,’ but now in 2010 so far, the Sun has had spots been spotless for only 35 days. With the last solar maximum occurring in 2001, maybe the Sun is just now ramping up to the next maximum, which is set for 2013. Recent solar flares on August 1 and 7, and now these sunspots may be signaling that the Sun is “throwing off the covers” and starting to wake up.
This marvelous image from the Solar Dynamics Observatory shows that at about 8:55 UTC on August 1, a measurable solar flare triggered an event known as a coronal mass ejection (CME). This is where the “atmosphere” of the Sun sends out a burst of energized plasma. In this case, nearly the entire Earth-facing side of the Sun was involved.
The High Energy Astrophysics Picture of the week Page used that great “covers” analogy:
The Sun, after a long sleep, is finally waking up. And like any irascible sleeper vigorously throwing off the covers. In this case the covers are composed of high-energy electrons and protons being shot out into space at a tremendous rate. The image above, obtained by the Solar Dynamics Observatory on August 1, shows almost the entire earth-facing side of the sun erupting at once. In this extreme ultraviolet image you can see evidence of extremely ultraviolent activity: a C3-class solar flare (white area on upper left), a solar tsunami (upper right), multiple filaments of magnetism lifting off the stellar surface, large-scale shaking of the solar corona, and a coronal mass ejection. The coronal mass ejection, or CME, showered the earth with charged particles, producing spectacular aurora (northern lights) as far south as Iowa and Telemark, Norway.
And another CME on August 7 has not yet triggered a major geomagnetic storm, but high latitude sky watchers should take a look tonight, just in case.
Have you been checking out the Solar Dynamics Observatory website and seeing all the amazing, high resolution images of our closest star? If not, you should. Above is a great new video of SDO’s capabilities and latest images. If you want to see what the Sun looks like right now, go to SDO’s homepage. And here’s a link to the SDO image browser where you can see the different images in different wavelengths from the AIA (Atmospheric Imaging Assembly) and HMI (Helioseismic and Magnetic Imager). If you choose the date range option, you can see a “movie” of the Sun’s activity. For example, check out the enormous coronal hole in the northern hemisphere seen last week in AIA 193 (date range 6/28 to 7/3), allow all the images to download and then press “Play.” Completely awesome. The SDO website should be part of your daily internet routine!
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So, how many Earths can fit in the Sun? The answer is that it would take 1.3 million Earths to fill up the Sun. That’s a lot of Earths.
The Sun makes up 99.86% of the mass of the Solar System. And it’s the giant planets like Jupiter and Saturn which make the most of that remaining .14% of the Solar System.
If you’d like to do the calculation yourself, here are your numbers. The volume of the Sun is 1.412 x 1018 km3. And the volume of the Earth is 1.083 x 1012 km3. So if you divide the volume of the Sun by the volume of the Earth, you get 1,300,000.
Of course, the Sun is a fairly average sized stars. There are some enormous stars out there. For example, the red giant Betelgeuse has a radius of 936 times the radius of the Sun. That gives it hundreds of millions of times more volume than the Sun.
And the largest known star is VY Canis Majoris, thought to be between 1800 and 2100 times the radius of the Sun.
A new view of the sun from the Solar Dynamics Observatory. Credit: NASA
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Already, the Solar Dynamics Observatory, or SDO, has taken over 5 million images, and the firehose of data and spectacular images is allowing solar scientists to begin understanding the dynamic nature of solar storms. With SDO, scientists are seeing that even minor solar events can have large effects across the Sun. “In essence, we are watching the butterfly effect in action on the Sun,” said Dean Pesnell, SDO project scientist.
The Atmospheric Imaging Assembly (AIA), one of three instruments aboard SDO, records high-resolution full-disk images of the Sun’s corona and chromosphere in more channels and at a higher rate than ever before. “This will allow us to zoom in on small regions and see far more detail in time and space, and zoom in on any part we want,” said Pesnell. “By looking at entire Sun we can see how one part of the Sun affects another. You can then zoom in to measure the changes in great detail.”
Large eruptive prominence on the sun's edge, as seen by SDO. Credit: NASA
Shortly after AIA opened its doors on March 30, scientists observed a large eruptive prominence on the sun’s edge, followed by a filament eruption a third of the way across the star’s disk from the eruption.
“Even small events restructure large regions of the solar surface,” said Alan Title, AIA principal investigator at Lockheed Martin Advanced Technology Center. “It’s been possible to recognize the size of these regions because of the combination of spatial, temporal and area coverage provided by AIA.”
At the 216th American Astronomical Society meeting this week, Title said that some of the initial data from SDO is providing maps of magnetic fields and movies that are giving scientists some confidence in trying to decipher the cause and effect of solar storms
AIA observed a number of very small flares that have generated magnetic instabilities and waves with clearly-observed effects over a substantial fraction of the solar surface. The instrument is capturing full-disk images in eight different temperature bands that span 10,000 to 36-million degrees Fahrenheit. This allows scientists to observe entire events that are very difficult to discern by looking in a single temperature band, at a slower rate, or over a more limited field of view.
Solar storms produce disturbances in electromagnetic fields that can induce large currents in wires, disrupting power lines and causing widespread blackouts here on Earth. The storms can interfere with global positioning systems, cable television, and communications between ground controllers and satellites and airplane pilots flying near Earth’s poles. Radio noise from solar storms also can disrupt cell phone service.
To help scientists and the public to understand and have access to the large amount of data being returned by SDO, the science team has built some tools to help communicate the data.
New websites will help researchers find data sets relative to their topics of interest and provide an overview to the casual observer.
“SDO generates as much data in a single day as the TRACE mission produced in five years,” said Neal Hurlburt from SDO mission, from Lockheed Martin. “We want to share it with the public, but we want to do it in an effective way, so we developed the Heliophysics Events Knowledgebase (HEK) and the Sun Today Website.”
The Sun Today website displays the current state of events on the sun. These can guide researchers and others to more detailed descriptions and access to associated SDO data.
HEK includes the Event and Coverage Registries (HER, HCR), Inspection & Analysis Tools, Event Identification System and Movie Processing. Event services enable web clients to interact with the HEK.
There is also a tutorial on how to work with the data, and extract images and movies from the SDO data.
View of action on the Sun during this past week. Credit: NASA/SDO team
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Images and data are starting to roll in from the Solar Dynamics Observatory, and the images are nothing short of stunning. So, the SDO website has started a couple of new image gallery features, which will provide a “best of” weekly fix without overloading your Sun senses (and no sunscreen needed!) The first one is Pick of the Week. The image above is the first “pick” and what a pick it is! This SDO close-up shows a filament and active region on the Sun, taken in extreme UV light on May 18, 2010. It shows a dark and elongated filament hovering above the Sun’s surface, with bright regions beneath it. The filaments are cooler clouds of gas that are suspended by tenuous magnetic fields that are often unstable and commonly erupt. This one is estimated to be at least 60 Earth diameters long (about 805,000 km, or 500,000 miles). Wowza!
Solar flare on May 17, 2010, as seen by the AIA instrument on SDO. Credit: NASA
Hot Shots will feature some great looking flares. This image from the Atmospheric Imaging Assembly (AIA) instrument shows a solar eruption and a flare. The dark regions show the site of evacuated material from the eruption, and the large magnetic loops were formed during the flare. AIA takes images of the solar atmosphere in multiple wavelengths to study link changes in the surface and how they related to interior changes in the Sun. AIA takes images of the Sun in 10 wavelengths every 10 seconds.
A full-disk multiwavelength extreme ultraviolet image of the sun taken by SDO on March 30, 2010. False colors trace different gas temperatures. Reds are relatively cool (about 60,000 Kelvin, or 107,540 F); blues and greens are hotter (greater than 1 million Kelvin, or 1,799,540 F). Credit: NASA
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NASA’s newest solar satellite is officially open for business and all we can say is, “Wow!” The Solar Dynamics Observatory (SDO) released its “first light’ images on Wednesday, showing incredible views of the sun, with extreme close-ups, never-before-seen detail of material streaming outward from sunspots and high-resolution looks at solar flares across a wide range of ultraviolet wavelength.
“These initial images show a dynamic sun that I had never seen in more than 40 years of solar research,” said Richard Fisher, director of the Heliophysics Division at NASA. “SDO will change our understanding of the sun and its processes, which affect our lives and society. This mission will have a huge impact on science, similar to the impact of the Hubble Space Telescope on modern astrophysics.”
SDO launched in February and has been billed as the “Crown Jewel” of NASA’s fleet of solar observatories. This technologically advanced spacecraft is able to take images of the sun every 0.75 seconds and daily send back about 1.5 terabytes of data to Earth — the equivalent of downloading 380 full-length movies every day. The following graphic compares the capabilities of SDO with other missions and resolutions.
This image compares the relative size of SDO's imagery to that of other missions. Credit: NASA
Serendipitously, shortly after the instruments opened their doors, our recently quiet Sun began to get a little more active. The video below was created from data from the Atmospheric Imaging Assembly, a group of four telescopes designed to photograph the sun’s surface and atmosphere. This data is from March 30, 2010, showing a wavelength band that is centered around 304. This extreme ultraviolet emission line is from singly ionized Helium, or He II, and corresponds to a temperature of about 50,000 degrees Celsius.
This movie captures only a fraction of SDO’s imaging capabilities. It shows the Sun’s magnetic field followed by only four of SDO’s 12 imaging wavebands. You’ll see an eruption, flare, and dimming (dark regions evacuated by the eruption) by observing the event in several different layers of the atmosphere. If you’re wondering why the movie doesn’t show all 12 layers at full resolution it’s because at high-res the movie would be nearly a third of a gigabyte in size.
The Helioseismic and Magnetic Imager maps solar magnetic fields and looks beneath the sun’s opaque surface. HMI was undergoing a series of adjustments when it captured an eclipse of sorts. SDO’s view was partially blocked by the Earth. At the edges of the shadow, the Sun’s shape bends, due to the light’s refraction by the Earth’s atmosphere. SDO will have two “eclipse seasons” each year, when the orbit of SDO will intersect the Sun-Earth line.
For more images and a high-res version of the top image, see the SDO website.
Just remember — this is only the beginning of SDO’s mission!
This great new video (just uploaded today!) does a great job of explaining the upcoming Solar Dynamics Observatory (SDO) mission, which is slated to launch on Feb. 9, 2010. SDO will provide a new eye on the sun that will deliver solar images with 10 times better resolution than high-definition television. This mission will zoom in on the cause of severe space weather—solar activity such as sunspots, solar flares, and coronal mass ejections. It will give us the best look ever at our Sun.
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We all like to know in advance what the weather is going to be like, and space weather is no different. However, predicting solar storms from the sun — which can disrupt satellites and even ground-based technologies — has been difficult. But now scientists say magnetic loops breaking inside the sun provide two to three-day warnings of solar flares. “For the first time, we can tell two to three days in advance when and where a solar flare will occur and how large it will be,” said Alysha Reinard, from the NOAA Space Weather Prediction Center.
Reinard and her team found that sound waves recorded from more than 1,000 sunspot regions reveal disruptions in the sun’s interior magnetic loops that predict a solar flare. They found the same pattern in region after region: magnetic twisting that tightened to the breaking point, burst into a large flare, and vanished. They established that the pattern could be used as a reliable tool for predicting a solar flare.
“These recurring motions of the magnetic field, playing out unseen beneath the solar surface, are the clue we’ve needed to know that a large flare is coming—and when,” said Reinard. Twisting magnetic fields beneath the surface of the sun erupt into a large solar flare, as shown above. Credit: NOAA
The new technique is already twice as accurate as current methods, according to the authors, and that number is expected to improve as they refine their work over the next few years. With this technique, reliable watches and warnings should be possible before the next solar sunspot maximum, predicted to occur in 2013.
“Two or three days lead time can make the difference between safeguarding the advanced technologies we depend on every day for our livelihood and security, and the catastrophic loss of these capabilities and trillions of dollars in disrupted commerce,” said Thomas Bogdan, director of NOAA’s Space Weather Prediction Center.
The team’s paper has been accepted for publication by the Astrophysical Journal Letters.
