Monster sunspot could stir up auroras

The sun photographed this morning by NASA’s Solar Dynamics Telescope at 11:30 a.m. CDT this morning October 18. Credit: NASA

Not today and not tomorrow, but a monster sunspot group rounding the eastern limb of the sun could spunk up the fall aurora season. Active region 2192 harbors a Jupiter-sized sunspot that’s just now visible with the naked eye using a safe solar mylar filter or #14 welder’s glass. I spotted it very close to the southeastern edge of the sun today. In the coming days, it will rotate into better view, making for an easy catch with the naked eye or small telescope. I can’t emphasize enough the importance of a safe filter. You can purchase one HERE for naked eye viewing or HERE for your telescope.

Coronal mass ejection shot out by flare activity in new sunspot group 2192 on October 14 before it even rounded the sun’s limb. Image from the SOHO coronagraph. Click for video. Credit: NASA/ESA

Even before the behemoth came into view, it spawned a brilliant coronal mass ejection on October 14 and several M-class medium strength flares. If we assume that the giant spot stays potent, the sun will rotate it around to face Earth in about 6 days. Flaring and other activity would then stream in our direction.

It will also spice up the partial solar eclipse next Thursday afternoon. Watch for the black limb of the moon to not only eclipse the sun but this sunspot too!

Update: Sunspot group 2192 unleashed an strong X-1 class flare around midnight Oct. 18-19. Any material it may have launched into space would have missed Earth by a wide margin because of the group’s position near the sun’s edge.

Huge sunspots scar the sun this week

Ten groups including three visible with the naked eye protected with a safe filter dot the sun today. Photo by the Solar Dynamics Observatory (SDO) taken at 8 a.m. CDT today July 9. Credit: NASA

A trio of impressive sunspot groups are parading across the sun’s face this week. Regions 2108, 2109 and 2110 are all closely-spaced and near the center of the disk today. All three require nothing more than a pair of eyes and a safe solar filter to view.

The sun seen through a standard 200mm telephoto lens and solar filter this morning gives you an idea of how the big sunspot groups look to the naked eye. Credit: Bob King

I took a look through my handy #14 welders glass this morning and saw 2110 distinctly; the other two groups blended into a single ‘spot’ at first. Looking closely I could barely split them into two separate dots. The view was spectacular at 30x in my little telescope with a total of ten sunspot groups and lots of fine detail in the three biggest.

Given high sunspot counts, the chance for flaring has been increasing in recent days. Today there’s a 75% chance for moderately strong M-class flares and 20% chance for the most powerful X-class variety.

Safe solar filters come in several varieties of optical / coated plastic and glass. Click to see ones you can purchase from Rainbow Symphony. Credit: Bob King

Curiously, none of the three biggies has shot off a large flare in the past day or two; they’re all currently stable. But the inconspicuous group 2113 fired off a beefy M6 flare only yesterday. It’s not expected to affect Earth, but because 2113 hides a complex magnetic field, future M-class or stronger blasts may be possible.

M6-class solar flare eruption from sunspot group 2113 captured July 8, 2014 at 11:24 a.m. by SDO. Credit: NASA

It seems like we’re due for aurora, so I’d be surprised if the current activity doesn’t lead to at least a minor storm soon. I’ll keep you updated.

Polka dots and sunbeams a solar observer’s dream

Sunspots speckle the sun like polka dots in this photo taken early this morning by NASA’s Solar Dynamics Telescope (SDO). The largest spot (right of center) belongs to sunspot group 2055. The view is very similar to that seen through a typical amateur telescope equipped with a safe solar filter. Sunspots are regions where magnetic energy is concentrated on the sun’s surface. Credit: NASA

For a change it was wonderful to show people a heavily speckled sun at Astronomy Day festivities yesterday. If it’s clear – rare enough in itself – sunspots are usually little more than crumb-sized and look like flecks of dirt or dust through the eyepiece.

Kids and adults eager to see sunspots queue up at Jim Schaff’s dual telescopes, which showed the sun in both visible light and deep red hydrogen-alpha. Schaff, of Duluth, is at left. Credit: Bob King

But this week the past few days, the sun’s been showing off a half dozen spots as large or larger than the planet you toil upon. There are currently at least 8 numbered sunspot groups. One of them, the leader spot in group 2055, was easily seen through a #14 welder’s glass this morning.

A C4-class flare in sunspot region 2055 early yesterday evening May 10 glares in this photo made in ultraviolet light by SDO. More flares up to M-class are possible from this region in the coming days. Credit: NASA

To be visible with the naked eye (with filter), a sunspot or sunspot group has to extend some 31,000 miles (50,000 km) or about 4 times the diameter of Earth. While enormous, about 2-3% of sunspots and sunspot groups or about 100 per 11-year solar cycle can be seen by a dedicated solar observer, proving you don’t need a telescope to follow the general trend of the 11-year sunspot cycle.

The first drawing of sunspots was made by English monk John of Worcester in 1128 A.D.

The first written records of sunspots come to us from the Chinese as long ago as 800 B.C. Court astrologers in China and Korea kept tracks of spots because they believed they foretold important events. The earliest known drawing of sunspots was made almost 500 years before the invention of the telescope by English monk and chronicler John of Worchester. On Dec. 8. 1128 A.D., Brother John wrote:

“…from morning to evening, appeared something like two black circles within the disk of the Sun, the one in the upper part being bigger, the other in the lower part smaller. As shown on the drawing.”

First photo of the sun using the daguerrotype process taken by Fizeau and Foucault on April 2, 1845. Though fuzzy, you can still make out sunspot groups and the basic dark umbra-lighter penumbra structure of the spots. Credit: ESA

His sighting was followed five days later by a red aurora recorded over Korea. The two may have been related.

As long as we’re talking firsts, the first successful photograph of the sun and sunspots was made on April 2, 1845 by French physicists Louis Fizeau and Leon Foucault on daguerrotype with an exposure of 1/60 of a second. It looks pretty rough but photography only improved from there.

Nowadays, anyone with a safe solar filter for either naked eye or telescope use can see what the sun’s up to. Solar telescopes in orbit and on the ground photograph the sun almost continuously. NASA’s dual STEREO orbiting solar probes even show us what’s happening the side facing away from Earth.

A prominence eruption blasted a CME or coronal mass ejection off the northeast side of the sun very early this morning. It’s not Earth-directed. This photo was taken by the Solar and Heliospheric Observatory (SOHO) which uses a disk to block direct sunlight. Credit: NASA/ESA

We not only want to learn more about how the sun works, but we’re justifiably concerned about its storms and how they affect our planet.

Big sunspot convulses but all quiet on the aurora front … for now

Sunspot region 1967 is so big it easily popped into view through a “cloud filter” Sunday afternoon Feb. 2. The group is visible with the naked eye properly shielded by a safe solar filter. Details: 350mm lens at f/11, ISO 200 and 1/2000″. Credit: Bob King

What a crazy sunspot cycle. Weeks go by with only a few tiny spots freckling the sun, then all at once a monster group big enough to swallow 10 Earths rounds the eastern limb and we’re back in business. I’m happy to report we’ve got another behemoth snapping and crackling with M-class (moderately strong) flares. That would be Active Region 1967, the hunk a hunk of burnin’ sun we checked out a few days ago.

NOAA weather forecasters predict an 80% chance of continued M-flares and a 50% chance over the next 3 days for considerably more powerful X-class flares. This sunspot group has a delta classification magnetic field, the Facebook equivalent of “it’s complicated”.

Sunspots are made of a dark umbra and lighter penumbra. Very tiny spots with no penumbrae are called pores. A close up of the sun’s photosphere shows a finely granulated texture. Granules are cells of hot gas about the size of Texas that rise from below, cool and sink. Each lasts from 8 to 20 minutes. Credit: NASA

Sunspots have two parts: a dark core (or cores) called an umbra surrounded by a paler skirt of magnetic energy, the penumbra. They can look impressive like this one, but it’s hard to call a sunspot a “thing”. It’s really more of a location on the sun’s bright white photosphere where bundles of powerful magnetic energy bob up from below the surface and insulate a region of the sun’s fiery hydrogen gas from the rest of the flaming globe.

We’re talking insulate as in staying cool. While the photosphere cooks at around 11,000 degrees Fahrenheit, sunspots are some 3,000 degrees cooler. That’s why they appear dark to the eye. If you could rip them away from the sun and see them alone against the sky, they’d be too bright to look at.

Close up of AR 1967 photographed by the Solar Dynamics Observatory at 6:45 p.m. CST Feb. 3, 2014. The group’s shape reminds me of the Big Dipper. Credit: NASA

A delta-class spot group has umbrae of both polarities, north and south, corralled within the penumbra. Like bringing opposite poles of a two magnets so close they snap together, something similar happens inside delta-class groups. Only instead of a snap, a titanic thermonuclear explosion called a flare goes kaboom.The biggest flares release the equivalent of more than a billion hydrogen bombs.

We thank our lucky stars for the 93 million miles separating sun and Earth. AR 1967 has paraded right in front of our noses as it rotated with the sun. Today it squarely faced the Earth – a good thing when it comes to the particle blasts that fire up the northern lights. Let’s hope it showers us with a magnetic goodness in the coming days. I really miss seeing the aurora. You too?

Big sunspot livens up a quiet sun / Chance for auroras overnight Feb. 1-2

Sunspot region 1967 dominates the solar disk in this photo made late Jan. 31 by the Solar Dynamics Observatory. Credit: NASA

Sunspot group 1967 burst onto the scene on Jan. 28. Now it’s big enough to easily see with the naked eye through a safe solar filter. The group’s twisty, complex magnetic field has already ignited a significant M6 flare on the 30th with a 60% chance for more M-class flares in the next three days.

The expanding cloud of solar plasma called a coronal mass ejection caught blasting away from sunspot group 1967 on Jan. 30 photographed by the Solar Heliospheric Observatory. Credit: NASA/ESA

The Jan. 30 event kicked out a high-speed proton-electron soup called a coronal mass ejection, a part of which will graze Earth overnight tonight (Feb. 1-2) and may spark a northern light display at high latitudes. Of course there’s always a chance southern Canada and the northern border states of the U.S. will see some action, too.

Since there’s been such a dearth of auroras of late, I wanted to share this bit of potentially good news. I’ll post updates if the lights make an appearance.

Aurora Alert! – Good chance for northern lights tonight and tomorrow Jan. 8-9

A bright curtain of aurora drapes the northern sky two summers ago. Credit: Bob King

It’s not often you see “major” and “severe” geomagnetic storms in the space weather forecast, but here it is:

“Quiet to severe storm levels on day one (9 Jan.), unsettled to severe storm levels on day two (10 Jan.) …”

These dates are Greenwich time so Jan. 9 means sometime overnight tonight (Jan. 8-9) for U.S. and Canadian time zones. All this excitement is brought to you by the current huge sunspot group known as Active Region 1944, which contains one of the biggest sunspots seen in years.

Big sunspot group 1944 at 4:45 p.m. CST today. Credit: NASA

The entire works spans some 125,000 miles (200,000 km) or more than 15 times the size of the Earth. It’s spawned multiple M-class (moderate) flares and at least one X-class (strong) flare in the past couple days, sending high-speed streams of protons and electrons in Earth’s direction.

There’s an 80% chance of additional M-class and 50% chance of X-class flare from this very active group in the coming days. Sunspot groups are regions on the sun’s surface where magnetic energy is strongly concentrated like a giant bar magnet with north and south poles. In simple groups, the positive and negative magnetic poles are separated from one another and not likely to come in contact and cause trouble. Astronomers say these groups have a “beta” magnetic classification.

The X1-class flare that popped off earlier yesterday Jan. 7 in the big sunspot group cut loose a large, high-speed cloud of particles called a coronal mass ejection. Some of that material will start arriving in Earth’s vicinity late tonight. Click to see animation. This photo was taken with the SOHO coronagraph. Credit: NASA/ESA

Huge complicated groups like 1944 have a beta-gamma-delta magnetic field where spots of opposite polarities lie near one another with no clear division between them. This is where things get volatile. The more complicated a sunspot group’s magnetic field becomes, the greater the potential for magnetic mischief. Opposite polarities can interact in the churnin’, burnin’ solar soup and spawn strong flares.

When those speedy particles arrive and hook in to Earth’s magnetic field, which we dearly hope will happen, they spiral toward our magnetic poles, crashing into air molecules and exciting them to fluoresce as northern lights.

Let’s hope that transpires either tonight or tomorrow night. The moon – now just over half – won’t be enough to wash out the sky like a full moon would, and it sets just after 1 a.m., leaving a completely dark sky. Cross your fingers and get ready – the sky may go electric tonight. It’s clear here in Duluth, Minn., so I’ll be monitoring and updating.

UPDATE: 9:30 a.m. CST today: Expected northern lights didn’t happen overnight. Nothing seen from Duluth, Minn.. Chances are even better for auroras to break out tonight, so don’t give up the vigil. I’ll update later today.

Big Sunspot Group Turns Earth’s Way / Comet ISON Photo a False Alarm

Sunspot region 1944 has a complicated beta-gamma magnetic field making it prone to producing flares. Photo taken by the Solar Dynamics Observatory at 9:15 a.m. CST today. Click to enlarge. Credit: NASA

We knew it was big even when it rounded the sun’s limb two days ago, but now that sunspot group 1944 has rotated into clear view, we can truly appreciate its enormity. Based on my rough estimate, the largest spot in the group is now easily 40,000 miles across or five times the diameter of Earth and one of the largest of the current solar cycle.

Sunspot group photographed through a “cloud filter” with a 300mm lens this morning Jan. 4, 2014. With a safe solar filter, the group is big enough to see with the naked eye. Credit: Bob King

The group has banged off several moderate M-class flares in the past 24+ hours. NOAA space weather forecasters are calling for a 75% chance of additional M-flares and a 30% chance for powerful X-flares in the days ahead.

Given that the group’s predicted arc across the rotating sun will soon place it squarely in Earth’s direction, we hope that it continues to percolate with flares, potentially sparking auroras in the nights ahead.

Earth and moon size illustration compared to today’s photo of the large sunspot group. Credit: NASA

Using a #14 welder’s glass I could easily see the sunspot region as a dark dot in the lower right corner of the sun with my naked eye this morning. If you have a safe solar filter or a telescope equipped with one, take a look and be impressed.

The sausage-shaped glow running from upper left to lower right in the left-side negative image was suspected to be Comet ISON’s remnant. Photo at right shows nothing at ISON’s position on Jan. 1, 2014. The blue dot marks the predicted position of the comet; the green type gives the names of stars. Click for more images and information. Credit: Hisayoshi Kato

In other news, Japanese amateur astronomer Hisayoshi Kato made a deep image of Comet ISON’s location on December 29 using a 180mm f/2.8 telephoto lens near the Mauna Loa Observatory in Hawaii, recording a possible sausage-shaped dust remnant. Because long time exposures and electronic image processing can sometimes introduce artifacts into an image, Kato photographed ISON’s position again on Jan. 1 but came up empty handed.

No similar remnant stood out on the second try indicating his original photo didn’t capture the comet after all. Some of us were hopeful he had. So what is that dusty sausage? Possibly a strand of the Integrated Flux Nebula, a flock of dust clouds threading the galaxy that glow not by the light of a nearby star(s) but instead from the integrated flux of all the stars in the Milky Way. Think of it as stellar light pollution.

Forecast: Explosive sunspots with a chance for auroras tonight, this weekend

Venus shines above a beach in Maui, Hawaii late last week. Island of Lanai in the distance. Waves are lit by firelight. Credit: Bob King

Just returned from a wonderful trip to the island of Maui in Hawaii where Venus shines high in the western sky after sunset and a handful of professional observatories track the comings and goings of wayward satellites, comets and asteroids from a dormant volcano 10,000 feet above the Pacific Ocean.  I’ll have more Maui astronomy to share with you soon, but for the moment, let’s focus on the sun.


Views of the sun in a variety of wavelengths of light showing the flares from sunspot groups 1875 (top right bright patch) and 1877. Solar Dynamics Observatory 

More than one sunspot group has been blasting stuff in Earth’s direction this week. The two largest sunspot groups – active region 1875 and neighboring 1877 – both have complex magnetic fields that have spawned hefty flares. 1875 kicked out a medium M4 flare on Oct. 22 while region 1877 upped the ante with a powerful M9 class flare Wednesday evening CDT.

The sun late this afternoon CDT Oct. 24 taken by the Solar Dynamics Observatory. Both regions 1875 and 1877 are big enough to see with the naked eye with a safe solar filter. Credit: NASA

The M9.3 is just below the X-class flare level, the most energetic category.  The material the explosion shot into space appears to be directed toward Earth with a possible arrival this weekend. Should northern lights materialize, a late-rising third quarter moon won’t spoil the show.

With this recent resurgence in solar activity after a summertime lull, things look promising. Space weather forecasters are calling for a 15 percent chance aurora overnight tonight for mid-northern latitudes overnight from earlier coronal mass ejections. Keep a watch – I’ll be out there too.

Chance for flares from bad-boy sunspot group 1875

Today’s sun is speckled with sunspot groups including region 1875 which is approaching the center of the disk. M-class flares are possible from the region, which if timed right, could up our chances for seeing auroras later this week. Credit: NASA / Solar Dynamics Observatory

We’ve been a dry spell for auroras the past couple weeks, but that could change if a large sunspot group now crossing the solar disk continues to grow and become more magnetically active.

Active region 1875 has no particularly large spots, but it does cover a lot of area and contains a complex beta-gamma-delta magnetic field. In ordinary language, it means that positive and negative magnetic poles are very close one another in the group. If opposite poles meet on the sun’s churning surface, vast amounts of energy are released in large flares, flinging clouds of electrons and protons toward Earth in a coronal mass ejection.

Space weather forecasters give the group a 30 percent chance of producing an M-class or medium-sized flares. These babies can cause radio blackouts in Earth’s polar regions and stir up minor to modest auroras. Region 1875 harbors a smaller chance for kicking out an X-class flare, the most powerful category.

We’ll keep an eye on the sun in the next few days to see what happens. You can check HERE for the current flare and aurora forecast. Amateurs with solar-filter equipped telescopes will have a good week of sun watching with many sunspot groups to enjoy.

Aurora encore may follow July 4 fireworks

July 4th fireworks at Duluth, Minnesota’s Bayfront Park. Credit: Bob King

Happy Fourth of July! I hope your day explodes with enjoyment.

Aurora time-lapse

Just don’t go to bed after the fireworks show before checking the northern sky. NOAA’s space weather prognosticators expect a small auroral storm to begin sometime tonight and continue through tomorrow night. There’s a 20% chance we’ll see action at mid-northern latitudes and a 60% chance at high latitudes, where one wonders if any auroras are seen to advantage this time of year. North of about 49 degrees north latitude, twilight lingers all night long during the summer months.

The forecasted northern lights are brought to you by a slower moving coronal mass ejection, a blast of particles from the sun usually caused by the explosive power of a solar flare.

Neighboring sunspot groups 1785 and 1787 photographed this morning with NASA’s orbiting Solar Dynamics Observatory. Credit: NASA/SDO

We may not have to wait too long for the next eruption. Sunspot group 1785, which rotated onto the sun earlier this week, is a large, complicated magnetic mess and harbors the energy to kick out powerful M-class flares. The sun’s rotation will bring it forward to face Earth more directly in the days ahead increasing the chances for more auroras.

M1.5 flare from sunspot group 1787 as it rounded the eastern limb of the sun early on the morning of July 3. Credit: NASA/SDO

Not far behind, sunspot cluster 1787 put on its own fireworks show when it first rotated around the sun’s limb early Wednesday morning, greeting astronomers with a moderate M1.5 flare.

How the sizes of Earth and moon compare to sunspots. Even an Earth-sized spot requires a telescope to see. The leader spot in the group 1785 is at least 3x larger than our planet. Credit: NASA

The big spot in 1785 is now large enough to see with the naked eye using a safe solar filter – I easily spotted it this morning as tiny dark fleck in the sun’s southeast quadrant. Sometimes we forget how big sunspots truly are. What looks like a tiny dot in a small telescope is about as big as the moon; Earth-sized spots are larger but ordinary by solar standards. This morning’s behemoth was easily thrice our planet’s diameter, and the group it belongs to spans some 8 Earth diameters.

A sunspot’s dark tone is deceiving. They only look that way because they’re 3,000 degrees cooler than the 11,000 degree photosphere, the glaring white “surface” of the sun. If we could remove the spots and see them alone against the black backdrop of outer space, they’d be much too bright to look at safely. Their size hints at the true vastness of the sun, an 863,700-mile-wide (1.4 million km) sphere of incandescent gas 4 times hotter than a handheld sparkler.