I wear glasses for astigmatism. But, as a stargazer with a visual impediment, turns out I’m in good company. The GREGOR telescope, a solar telescope located at the Teide Observatory in the Canary Islands also suffered from an astigmatism that was recently corrected…to very stellar results.
Opened in 2012, GREGOR is part of a new generation of solar (Sun observing) telescopes. Before 2002, solar scopes were quite small in diameter; under one metre. The Sun is close, and VERY bright, so your telescope doesn’t need to be as wide as those used for deep-space imaging. GREGOR itself is 1.5m (compare that to some of the largest telescopes imaging distant faint objects like the Keck Observatory at 10m. But without the special filters/optics used by a solar scope, a regular telescope staring at the Sun would be destroyed by the Sun’s light). A telescope’s power is often related to its ability to magnify. But just like enlarging a low-resolution photo, the more you magnify, the fuzzier the image becomes (that’s why those scenes in crime shows where they yell ‘enhance!’ and a photo grows to reveal a criminal are not realistic). Ultimately, a telescope’s diameter provides the higher resolution photo. GREGOR is designed to take those high-resolution images of our local Star. How high resolution? Imagine being able to distinguish a 50km wide feature on the Sun from 140 million km away – basically the same as being able to read the text on a coin from a kilometre away.
NASA’s Curiosity Rover spends most of its time staring at the ground, but like humans, it looks up once in a while too. As reported earlier, NASA ground controllers pointed the rover’s Mast Camera (mastcam) skyward to shoot a series of photos of Comet Siding Spring when it passed closest to the Red Planet on October 19th. Until recently, noise-speckled pictures available on the raw image site confounded interpretation. Was the comet there or wasn’t it? In these recently released versions, the fuzzy intruder is plain to see, tracking from right to left across the field of view.
Ten exposures of 25 seconds each were taken between 4:33 p.m. and 5:54 p.m. CDT on October 19th to create the animation. The few specks you see are electronic noise, but the sharp, bright streaks are stars that trailed during the time exposure. Curiosity’s Mastcam camera system has dual lenses – a 100mm f/10 lens with a 5.1° square field of view and a 34mm, f/8 lens with a 15° square field of view. NASA didn’t include the information about which camera was used to make the photos, but if I had to guess, the faster, wide-angle view would be my choice. Siding Spring was moving relatively quickly across the Martian sky at closest approach.
Prowling through the Curiosity raw image files, I came across this photo of the Sun on November 10th. Three dark spots at the left are immediately obvious and a dead-ringer for Active Region 2192, now re-named 2209 as it rounds the Sun for Act II. You’ll recall this was the sunspot group that nearly stole the show during the October 23rd partial solar eclipse. From Mars’ perspective, which currently allows Curiosity to see further around the solar “backside”, AR 2209 showed up a few days before it was visible from Earth.
Although it’s slimmed down in size, the region is still large enough to view with the naked eye through a safe solar filter. More importantly, it possesses a complex beta-gamma-delta magnetic field where magnetic north and south poles are in close proximity and ripe for reconnection and production of M-class and X-class flares. Already, the region’s crackled with three moderate M-class flares over the past two days. In no mood to take a back seat, AR 2209 continues to dominate solar activity even during round two.
Mars possesses two small moons, Deimos and Phobos. Curiosity has photographed them both before including an occultation Deimos (9 miles/15 km) by the larger Phobos (13.5 miles/22 km). Phobos orbits closer to Mars than any other moon does to its primary in the Solar System, just 3,700 miles (6,000 km). As a result, it moves too fast for Mars’ rotation to overtake it the way Earth’s rotation overtakes the slower-moving Moon, causing it to set in the west overnight. Contrarian Phobos rises in the western sky and sets in the east just 4 hours 15 minutes later. When nearest the horizon and farthest from an observer, it’s apparent size is just 0.14º. At the zenith it grows to 0.20º of 1/3 the diameter of the Moon.
One longish observing session on the planet would cover a complete rise-set cycle during which Phobos would first appear as a crescent and finish up a full moon a few hours later. All this talk about Phobos is only meant to direct you to the picture above taken by Curiosity on October 20, 2014 when the moon was a thick crescent. As on Earth, where Earthshine fills out the remainder of the crescent Moon, so too does Mars-shine provide enough illumination to see the full outline of Phobos.
Curiosity has also photographed Earth, sunsets and transits of Phobos across the Sun while rambling across the dusty red landscape since August 2012. Before we depart, it seems only fair to aim our gaze Mars-ward again to see what’s up. Or down. The rover’s been doing a geological “Walkabout” in the Pahrump Hills outcrop at the base of Mt. Sharp in Gale Crater since September. Earlier this fall it drilled and sampled rock there containing more hematite than at any of its previous stops. Hematite is an iron oxide that’s often associated with water.
The mission may spend weeks or months at the outcrop looking for and drilling new target rocks before moving further up the geological layer cake better known as Mt. Sharp.
That’s one big, black blemish on the Sun today! Rarely have we been witness to such an enormous sunspot. Lifting the #14 welder’s glass to my eyes this morning I about jumped back and bumped into the garage.
Properly shielded, it was very easy to see with the naked eye. Unlike some other naked eye sunspots, this one showed structure. The eastern end was darker, the western half grayer and more extended.
Watch the giant spot rotate into view and grow right before your eyes in this 72-hour time-lapse video taken by SOHO’s HMI imager Oct. 18-20, 2014
Through a small telescope, the mix of dark umbras scattered amid weirdly sculpted penumbral “islands” was incredible to see. Photographs like the one above are wonderful documents, but witnessing this beautiful complex magnetic mess with your own eyes is another experience altogether. Region 2192 continues to grow and size and complexity and is now the largest sunspot group of solar cycle 24which began in 2009 – more than five years ago!
Every sunspot marks a region on the Sun’s shiny outer skin called the photosphere where magnetic energy is concentrated. Strong magnetic fields within a sunspot group quell the turbulent churning of the photosphere, chilling the region by several thousand degrees. Sunspots appear dark against the Sun’s blazing disk because they’re cooler. Cooler meaning 8,000 F instead of 11,000 F, so yes, they’re still VERY hot.
Watch as Region 2192 crackles with energy and flares as seen in far ultraviolet light with NASA’s Solar Dynamics Observatory.
Energy stored in sunspots’ twisted magnetic fields can suddenly be released in violent, explosions called solar flares. Billions of tons of solar plasma – the sizzling mix of protons and electrons that composes the Sun – are heated to millions of degrees during the explosion and rapidly accelerated into space. Radiation from radio waves to X-rays and gamma rays fans out at the speed of light. Fortunately for us, our atmosphere and planetary magnetic field protect us from most of what flares can fling our way.
But as the Sun rotates this monster into our line of sight, possibilities for Earth-directed flares and coronal mass ejections increase as do geomagnetic storms, the bringer of auroras. Already in the past 48 hours, the spot has dished out seven M-class flares and a powerful X-1 flare even before it has fully come into view. There’s more to come – Region 2192 harbors an unstable beta-gamma-delta magnetic field ripe for additional flaring including more of the X-classvariety.
There’s no doubt now that this behemoth will stick around to add a whole new dimension to tomorrow’s partial solar eclipse. I can’t wait to see the Moon’s black curve approach and at least partially occult the group from view. If you’re interested in getting some one-of-a-kind pictures of the scene, please see our own Dave Dickinson’s excellent guide on photographing the partial eclipse.
While we’re on the Moon, early morning risers had the pleasure of its company just one day before New Moon and solar eclipse. I was out watching the Orionid meteor shower. While not rich like the Perseids or Geminids I managed to catch a few including a few lucky shots with the camera.
The shower has peaked but will still be active the remainder of the week if you’re inclined to take a look. And I can’t resist. How about one last sweet close-up photo of sunspot group 2192? I have a feeling you won’t mind.
It’s a-comin’: a “monster” sunspot is steadily rotating around the Sun’s southern hemisphere and will soon be in position to fire flares and CMEs in our direction — and this past weekend master solar photographer Alan Friedman captured it on camera!
The image above was taken in full-spectrum visible light on Sunday, Oct. 19 by Alan from his backyard in Buffalo, New York. Sunspots 2186 (at the top limb), 2187 (upper center), 2193 (the small middle cluster) and the enormous AR2192 are easily visible as dark blotches – “cooler” regions on the Sun’s surface where upwelling magnetic fields interrupt the convective processes that drive the Sun’s energy output.
This particular image was a single frame of video, unlike some of Alan’s other photographs. According to Alan the air turbulence was particularly bad that day, shooting between the clouds, so only this one frame was usable. Click the image for full-scale “wow” factor.
(And if you think AR2192 looks scary in that image, check it out in CaK bands here!)
According to Spaceweather.com AR2192 has grown considerably over the past few days and has the potential to unleash M- and X-class flares in our direction now that it’s moving into Earth-facing position. It’s currently many times larger than Earth and will likely get even bigger… in fact, during this week’s partial solar eclipse AR2192 should be visible with the naked (but not unprotected!) eye for viewers across much of North America.
Bim, bam, smash! The Sun hurled two clouds of particles in our general direction, putting space weather watchers on alert. There’s now a high chance of auroras on Sept. 12 (Friday), according to the National Oceanic and Atmospheric Administration, with more activity possible during the weekend.
The coronal mass ejections erupted Sept. 9 and Sept. 10 from sunspot AR2158. The Sept. 10 flare packed the strongest class punch the sun has, an X-flare, which briefly caused HF radio blackouts on Earth. We have some amateur shots of the sunspot and Sun below.
“Radio emissions from shock waves at the leading edge of the CME suggest that the cloud tore through the sun’s atmosphere at speeds as high as 3,750 km/s [2,330 miles per second],” wrote SpaceWeather.com. “That would make this a very fast moving storm, and likely to reach Earth before the weekend. Auroras are definitely in the offing.”
Active regions 2108 and 2109 are now passing around the limb of the Sun, but not before solar photography specialist Alan Friedman grabbed a few pictures of them on Friday! The image above, captured by Alan from his location in Buffalo, NY, shows the two large sunspots nestled in a forest of solar spicules while a large detached prominence hovers several Earth-diameters inside the corona. A beautiful snapshot of our home star!
Captured in hydrogen-alpha wavelengths, the image above has been colored by Alan, rotated 90 degrees counterclockwise, and inverted from the original. The sunspots and standing prominence are cooler in Ha than the surrounding chromosphere and corona, and so actually photograph darker.
A view of sunspot 2109 in visible light can be seen below:
Sunspots are the result of magnetic fields rising up from deep within the Sun, preventing convection from occurring in large areas on the Sun’s surface and thereby creating relatively cooler regions we see as dark spots. They can often be many times the size of Earth and can be sources of powerful solar flares.
See these and more images by Alan on his blog here.
Do you feel like you’re in the firing gallery? These sunspots are practically square-on to Earth right now. Although they haven’t shown much sign of erupting, if they did our planet would be right in the line of fire if a flare or stream of solar particles erupted.
These groups (known as 1785 and 1787) are so big that they are easily visible in amateur telescopes. 1785 alone is more than 11 Earth-diameters across, according to SpaceWeather.com! Just make sure you have the proper solar filters in place before you gaze at these dark smudges.
“Sunspots” — so called because they appear as dark smudges on the face of the sun — are areas of intense magnetic activity on the sun (thousands of times stronger than that of Earth’s magnetic field.)
At times, these regions can get so intense that the energy builds up and releases in the form of a flare and/or a coronal mass ejection — a burst of gas and magnetism that hurls solar material away from the sun.
If these flares hit the area of the Earth, a bunch of things can happen. Particles can flow along Earth’s magnetic lines and lead to the creation of aurora, or Northern/Southern lights. (Here’s an aurora that happened in June.) More severe storms can short out satellites or disable power lines.
“Could it be the calm before the storm?” SpaceWeather.com asked on its homepage, before giving forecasts of strong types of flares: “NOAA forecasters estimate a 55% chance of M-flares and a 10% chance of X-flares on July 8.”
We’ll keep our eyes peeled and let you know if something interesting happens. In the meantime, these pictures came from Universe Today readers, and we’d love to see your images, too! Feel free to add your snapshots to our Flickr page.
Update, 2:39 EDT: Among the pictures in our Flickr pool is this new stunner below from Ron Cottrell of Oro Valley, Arizona. “These sunspots are so magnificent that I get striking detail with my small 40mm Hydrogen-alpha telescope,” he wrote us.
Last night, as Commander Hadfield and the Expedition 35 crew were returning to Earth in their Soyuz spacecraft, the Sun unleashed yet another X-class flare from active region 1748, the third and most powerful eruption yet from the sunspot region in the past 24 hours — in fact, at a level of X3.2, it was the most intense flare observed all year.
And with this dynamic sunspot region just now coming around the Sun’s limb and into view, we can likely expect much more of this sort of activity… along with a steadily increasing chance of an Earth-directed CME.
According to SpaceWeather.com AR1748 has produced “the strongest flares of the year so far, and they signal a significant increase in solar activity. NOAA forecasters estimate a 40% chance of more X-flares during the next 24 hours.”
(Find out more about the classification of solar flares here.)
The sunspot region just became fully visible to Earth during the early hours of May 13 (UT).
Sunspots are regions where the Sun’s internal magnetic fields rise up through its surface layers, preventing convection from taking place and creating cooler, optically darker areas. They often occur in pairs or clusters, with individual spots corresponding to the opposite polar ends of magnetic lines.
Sunspots may appear dark because they are relatively cooler than the surrounding area on the Sun’s photosphere, but in ultraviolet and x-ray wavelengths they are brilliantly white-hot. And although sunspots look small compared to the Sun, they are often many times larger than Earth.
According to SDO project scientists Dean Pesnell on the SDO is Go! blog, AR1748 is not only rapidly unleashing flares but also changing shape.
“The movies show that the sunspot is changing, the two small groups on the right merging and the elongated spot on the lower left expanding out to join them,” Pesnell wrote earlier today.
Of course, as a solar scientist Pesnell is likely much more excited about the chance to observe further high-intensity activity than he is concerned about any dramatically negative impacts of a solar storm here on Earth, which, although possible, are still statistically unlikely.
“Great times ahead for this active region!” he added enthusiastically.
Active Region 1654 on the Sun’s western limb, seen by SDO on Jan. 11 (NASA/SDO/HMI team. Diagram by J. Major.)
Like an enormous cannon that is slowly turning its barrel toward us, the latest giant sunspot region AR1654 is steadily moving into position to face Earth, loaded with plenty of magnetic energy to create M-class flares — moderate-sized outbursts of solar energy that have the potential to cause brief radio blackouts on Earth and, at the very least, spark bright aurorae around the upper latitudes.
According to SpaceWeather.com, AR1654 “could be the sunspot that breaks the recent lengthy spell of calm space weather around our planet.”
The image above, captured by NASA’s Solar Dynamics Observatory earlier today, shows the structure of AR1654 upon the Sun’s photosphere — its light-emitting “surface” layer. Stretching many tens of thousands of miles, this magnetic solar blemish easily dwarfs our entire planet. And it’s not just a prediction that this sunspot will unleash a flare — it already has.
AR1654 came around the limb of the sun crackling with activity. Shortly after the probability of AR1654 releasing a flare was raised to 50% it did just that, letting loose with a burst of magnetic energy that was observed by SDO’s multi-channel cameras. Watch the video below:
Peaking at 9:11 UTC, this M1-class flare won’t have much more effect on Earth than perhaps some radio and GPS interference and maybe increased auroral activity. But AR1654 is still evolving and growing… and moving to face us.
In the meantime, solar astronomers and observatories like SDO are keeping an ever-watchful eye on this magnetic monster.
UPDATE 1/12: According to the NOAA, AR1654 has a 5% chance of producing an X-class flare, based on its current magnetic activity and alignment.
A sunspot is a magnetically active region on the sun that appears dark because it’s relatively cooler than the surrounding area—6,000ºF (3,300ºC) versus 10,000ºF (5,500º C). Sunspots are where solar flares are most likely to occur since the magnetic fields in these active regions can build up enough energy to break, releasing bursts of intense radiation into the solar system.
NASA’s High Resolution Coronal Imager (Hi-C) mission, launched Wednesday, July 11 from White Sands Missile Range in New Mexico, successfully returned (as promised!) the highest-resolution images of the Sun’s corona ever acquired. These images of the dynamic million-degree region of the Sun’s atmosphere will provide scientists with more information on the complex activity found near the Sun’s surface and how it affects space weather throughout the Solar System.
Launched aboard a 58-foot-tall (17 meter) Black Brant sounding rocket, Hi-C was equipped with exceptionally well-made mirrors — some of the finest ever made, according to the mission report. These mirrors allowed Hi-C to image a section of the Sun’s corona in extreme ultraviolet light with a resolution of 0.1 arcsec/pixel, distinguishing features as small as 135 miles (217 km) across. That’s five times the resolution of SDO images, or any previous space telescope for that matter.
That’s like the difference between watching a program on a tube television and an HD flatscreen monitor.
The image below shows the same region as seen by SDO’s AIA array and Hi-C’s innovative mirror-and-“light-maze” system:
“These revolutionary images of the sun demonstrate the key aspects of NASA’s sounding rocket program, namely the training of the next generation of principal investigators, the development of new space technologies, and scientific advancements,” said Barbara Giles, director for NASA’s Heliophysics Division at NASA Headquarters in Washington.
During its 620-second suborbital flight, Hi-C took 165 images of a section of the Sun’s corona 135,000 miles (271,000 km) across, capturing wavelengths of light at 193 Angstroms emitted by the Sun’s super-hot 1.5 million kelvin corona. The images were focused on a large sunspot region, whose position was accurately predicted 27 days prior to launch.
“We have an exceptional instrument and launched at the right time,” said Jonathan Cirtain, senior heliophysicist at NASA’s Marshall Space Flight Center in Huntsville. “Because of the intense solar activity we’re seeing right now, we were able to clearly focus on a sizeable, active sunspot and achieve our imaging goals.”
Even though Hi-C’s flight only lasted ten minutes, of which 330 seconds were used for acquiring images, the amount of data gathered will be used by researchers for months.
“Even though this mission was only a few minutes long, it marks a big breakthrough in coronal studies,” said Leon Golub, lead investigator from the Harvard-Smithsonian Center for Astrophysics. “The Hi-C flight might be the most productive five minutes I’ve ever spent.”
Watch a 10-second video of the region shown above, seen from both Hi-C and SDO: