Tag Archives: sunspot

Morning aurora topped off by avian cheer

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A pretty series of rays sprouts above a pair of green arcs this morning around 3 a.m. CDT. Photo: Bob King

I got up for the stars but stayed for the birds. Clear skies overnight allowed for a look at a surprise aurora display, comets PANSTARRS and Lemmon, a handful of spectacular Eta Aquarid meteors and an attractive lunar crescent early this morning.

Three images from NASA’s Solar Dynamics Observatory were combined to create this spectacular view of last Friday’s flare. Credit: NASA

No auroras were predicted and true-to-forecast all looked quite at least through midnight. But at 2:30 this morning a bright green band spanned the northern horizon punctuated by one, two and occasionally an entire series of faint, rosy rays.

Sunspot group 1734′s largest spot – at left – is several times the diameter of Earth. This photo was taken this morning May 6, 2013. Credit: NASA

Expect more excitement courtesy of our parent star. Last Friday, a big flare erupted along’s the sun’s eastern edge, hurling a dragon-like tongue of incandescent hydrogen gas 120,000 miles (193,000 km) above the surface. Although this storm wasn’t directed toward Earth, the large sunspot group 1734 is currently nearly face-on to the planet and has the potential for strong flares. Cross your fingers.

A bright Eta Aquarid streaks across the northern sky and aurora this morning around 2:45 a.m. Photo: Bob King

I had planned to look at a variety of objects in the telescope but kept getting “distracted” by both the northern lights and regular appearances of incredibly fast, long-trailed meteors streaking across the northern sky from the east – Eta Aquarids.

Because the shower has a broad peak I encourage you to go out for a look yourself. Being so far north, I figured only a few might be seen here in Duluth, Minn. but was happily proven wrong. Had I simply sat in a lawn chair and stared skyward I’m certain I would have seen many more. Click HERE for more on the shower and how to view it.

A wide-field photo of Comet C/2011 L4 PANSTARRS shot on May 4, 2013. The comet is oriented the way it would appear shortly before dawn with the anti-tail pointing down and broad dust fan opening to the left. Credit: Joseph Brimacombe

Let me tell you about Comet PANSTARRS. In 10×50 binoculars I was surprised by how much there was to see under a dark sky. The V or fan-shaped tail spread is still obvious marked at its base by the small, brighter comet’s head. A second, straight anti-tail (debris left by the comet along its orbital path) stuck out like a pinkie finger from one side.

I estimated the whole works measured 1 degree or two full moon diameters across. While faint and smoky-looking at magnitude 7, the comet was very easy to pick out. In a 15-inch telescope PANSTARRS and its dual tails were brighter and better-defined; a tiny star-like nucleus peeped through the gases and dust concentrated in the its head. Very beautiful.

A morning topped off by the crescent moon is never wasted. Photo: Bob King

On to Comet Lemmon. I didn’t see it until 4 a.m. when dawn’s first light had already put its pale stamp on the eastern sky. I found it with difficulty in binoculars as a small, dim soft patch of light below the lower left star in the Square of Pegasus VERY low in the northeastern sky. It’s about as bright as PANSTARRS but low altitude and the onset of twilight combined to make it look fainter. In the scope, Lemmon was a big pale green fuzzball with a hint of a tail pointing southwest. Care to find it yourself? Here’s a map.

Wherever you are, enjoy the coming nights. If the moon’s your thing, an even thinner crescent will rise an hour before sunrise tomorrow in the east. Check for northern lights before you turn in tonight and use the map from yesterday’s blog to try your luck at Comet PANSTARRS … one last time.

 

A sunny slant of view on Earth Day

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A halo and circumscribed halo (upper bright saggy arc) around the sun this morning. Both are formed when light is bent or refracted through pencil-shaped hexagonal ice crystals. Photo: Bob King

Happy Earth Day! What a great planet to call home. Situated in our sun’s habitable zone and endowed with life and sweet pleasures, we know of no where else like it. I wouldn’t trade this blue gem for all the planets of Star Trek.

The sun photographed by NASA’s Solar Dynamics Observatory earlier this morning April 22. The large sunspot group at upper right can be glimpsed with the naked eye only through a safe solar filter. Click to enlarge. Credit: NASA

The sun broke through morning clouds today with two pleasant surprises – a colorful circumscribed halo caused by light refracted through billions of microscopic ice crystals in high cirrostratus clouds, and a pair of naked eye sunspots.

Through a safe solar filter, I spied two side-by-side black dots in the upper right (northwest) quarter of the sun.

High-resolution closeup of sunspot group 1726. Sunspots are cooler regions of concentrated magnetic energy on the sun’s surface. They usually have two parts – a dark, inner umbra enclosed by a lighter penumbra. Credit: NASA

They’re part of the large sunspot group 1726 that today spans more than a dozen Earth diameters (approx. 100,000 miles / 160,000 km). The group spawned a few flares, including a moderately strong M-class flare earlier this morning, and holds the potential for more.

Two cool snowpeople catch some April rays last week in Duluth, Minn. Photo: Bob King

In April the sun’s slant in the sky is the same as it is in mid-August, high enough to feel on your cheeks when you walk out the door. It brings welcome relief to some of us still mired in winter with several feet of snow piled up in the yard. The angle of the sun in the sky has much to do with the amount of heat our planet receives and the global climate.

The overhead sun covers a smaller area of ground with the maximum amount of energy (left). At right the sun is shown in winter when its lower angle spreads its light over a larger area with a loss of 100 watts of energy. Result? Colder weather. Credit: Randy Russell / windows2universe.org

If Earth were a gigantic flat disk instead of a sphere and had no atmosphere to filter sunlight, every square meter of ground would receive 1,368 watts of solar energy. Our planet’s spherical shape spreads the sun’s light out over a larger area, diluting the energy received to 342 watts. The atmosphere also filters out a small amount.

A different view of the sun’s angle in winter versus summer and its seasonal energy footprints.  Credit: Nicholas M. Short

When the sun is nearly overhead, as it is during summer, we get the full wattage and really feel the heat just like you would standing next to a 342 watt light bulb. In winter, the sun shines on the planet at a lower angle and its light spreads out broadly across the ground.

Since the amount of energy it’s beaming our way is constant, if it’s spread over a larger area, it becomes less concentrated and weaker. That’s one big reason why winter’s so cold – a lower sun means the intensity (energy) of sunlight is reduced. Without the customary heat to warm air and ground, rain becomes snow and accumulates.

The atmosphere also plays a part. In winter, the low sun shines spends much of the day shining through the lower levels of the atmosphere, where the air is thicker and dustier. Some of that light gets absorbed and some reflected away from Earth, further cooling the season.

Today’s angle suits me just fine. When I walked outside I felt the sun right away and knew it would be good day to celebrate another day of life on the planet. Wishing the same for you.

Fingernail moon, aurora watch and Comet PANSTARRS made easy

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The lunar crescent ascends the western sky over the next few nights dropping by two star clusters and one bright planet. The map shows the sky about an hour after sunset. Maps created with Stellarium

The moon has returned to sweeten the evening. Watch for a thin crescent low in the western sky tonight below the Seven Sisters star cluster. Tomorrow it moves upward, thickens a bit and shines near the V-shaped Hyades star cluster. Topping off the weekend, the crescent will stand just 2 degrees left of the planet Jupiter Sunday. If there ever was a gift that keeps on giving, it’s the moon.

To find PANSTARRS at dusk, use binoculars or a telescope and face northwest about 90 minutes after sunset. Look for the bright zigzag of Cassiopeia, point your instrument at the brightest star nearest the comet and “sta hop” in its direction. This map shows the sky 1 1/2 hours after sunset.

Time to catch Comet PANSTARRS … again. While it’s faded to near the naked eye limit, it’s still plainly visible in binoculars, particularly 7×50 or 10×50 models or larger. The comet is probably easier to find than ever because it’s passing through the bright W-shaped constellation Cassiopeia during the next two weeks. Look for it about 90 minutes after sunset in the northwestern sky. PANSTARRS has a brighter head topped by a faint, fan-shaped tail.

Face northeast about 90 minutes before sunrise and find the W of Cassiopeia. Use it to guide you to the comet.

While observers in the northern U.S., Canada and Europe will get equally good views at both dusk and dawn, sky watchers in the southern U.S. will have better luck at dawn when Cassiopeia is higher in the sky. The view through a telescope is still the best with the comet showing  a bright head and nucleus and a classic, gently-curving tail to the north.

Comet PANSTARRS with its amazing tail photographed on April 10 in Austria. Credit: Michael Jaeger

More good news. A strong solar flare erupted in sunspot group 1719 early Thursday morning April 11 sending sprays of solar protons and electrons in Earth’s direction. You know what that means.

The solar flare in sunspot group 1719 photographed in ultraviolet light by NASA’s Solar Dynamics Observatory around 3:30 a.m. CDT April 11. Credit: NASA

Major storm levels and auroras are possible overnight tonight through Sunday the 14th. With little interference from the moon, this could be a good show. I’ll be keeping an eye on the space weather and send out an alert this evening if auroras sprout.

 

What’s in store for sunspot cycle 24

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At least seven sunspot groups dot the sun this morning at 10 a.m. (CDT) as photographed by NASA’s Solar Dynamics Observatory (SDO). Sunspots are cooler regions where magnetic energy is concentrated. Sometimes that energy is released as a solar flare, propelling solar particles and radiation toward the Earth. Credit: NASA

Like you and I the sun has cycles. None of us escapes the day-night rhythm of sleep and wakefulness. The most visible of the sun’s rhythms is the 11 year solar cycle also called the sunspot cycle. These vary from 9 to 14 years but the average is 11.

In a typical cycle, the number of sunspots and solar storms begins at a minimum, rises to a maximum and then returns to minimum. During solar maximum the sun is peppered with sunspots and powerful, aurora-producing flares are common; at minimum the sun’s face can be blank for days or even weeks. Minimums and maximums also vary. Some peaks are longer and more sunspot-rich than others, while “valleys” can be short or long with variable spot numbers.

The peaks and valleys of the past 110 years of solar cycles. Sunspot numbers (shown at left) wax and wane in an approximately 11-year cycle.

The solar cycle was discovered by German astronomer Samuel Heinrich Schwabe in 1843 after he noticed sunspot numbers wax and wane in a regular pattern after 17 years of observation. Swiss astronomer Rudolf Wolf went back through previous sunspot records and reconstructed the sun’s ups and downs as far back as the mid-1700s.

Samuel Heinrich Schwabe

Each cycle gets a number. Solar Cycle 1 spanned the years 1755 to 1766. The last, Cycle 23, peaked in April 2000 with an average of 120 sunspots per day around the time of maximum. This was followed by a deep quiet period or minimum between cycles 23 and the current 24th with a record number of 801 spotless days between October 2005 and May 2010. This past solar minimum, which bottomed out in December 2008, was the longest and quietest in over a century. Since then, but especially over the past year, activity has been steadily on the rise.

The graph shows the last sunspot maximum in 2000 up through June this year. The current Cycle 24 is predicted to reach maximum next spring with an average of 60 spots a day. This would make it the smallest maximum in over 100 years. Credit: NASA

2012 has been a good year for sunspots, solar flares and auroras as we dig our way out of minimum and sail toward the next predicted peak in spring 2013. To date, the sun has kicked off about a half-dozen X-class flares. These are the most powerful variety with potential effects on Earth ranging from aurora creation to wreaking havoc with satellites and power grids. From late 2008 through early 2010 I recorded almost no auroras here in Duluth, Minn. In the past year however, we’ve been treated to several brilliant displays and at least 10 minor ones.

The brilliant flash is a  powerful solar flare that erupted in March 2012. Flares can affect the upper atmosphere (auroras), airplane communications, satellites, power grids and oil pipelines. Click image to see a spectacular video of a solar eruption that happened yesterday. Credit: NASA

NASA solar scientists predict a very weak maximum in 2013 with an average of 60 sunspots daily. If this holds true, Cycle 24 would be the least active since Cycle 14 which peaked in February 1906 at 64. While this sounds like bad news for aurora watchers, don’t put on your long face just yet. Every cycle max, even the wimpier ones, feature powerful flares and crazy space weather.

“Even a below-average cycle is capable of producing severe space weather,” says Doug Biesecker of the NOAA Space Weather Prediction Center. “The great geomagnetic storm of 1859, for instance, occurred during a solar cycle of about the same size we’re predicting for 2013.”

That storm, called the Carrington Event, is named after astronomer Richard Carrington who spotted a brilliant flare through his telescope on September 1, 1859.  Shortly before dawn the next day, the sky blew up in a brilliant display of northern lights visible as far south as Jamaica. Aurora-induced electric currents in telegraph lines shocked telegraph operators and set telegraph paper on fire.

“A report by the National Academy of Sciences found that if a similar storm occurred today, it could cause $1 to 2 trillion in damages to society’s high-tech infrastructure and require four to ten years for complete recovery,” according to a recent NASA press release.

We’ll soon see what Cycle 24 has in store. At the very least, more brilliant auroras are on the menu.

Super conjunction and auroras (we hope) highlight upcoming weekend

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Sunspot group 1520 is still ripe for more flares. It’s joined here by an entourage of additional groups. Photo taken at 8 a.m. (CDT) today July 13 by the Solar Dynamics Observatory. Credit: NASA

Aurora watchers get ready. Yesterday’s X1.4 class flare from big sunspot group 1520 unleashed a coronal mass ejection (CME) directly toward the Earth. This powerful enhancement in the solar wind will arrive sometime tonight or early tomorrow morning bringing with it a good possibility for auroras through Sunday.


A series of short time lapse videos of yesterday’s X1.4 flare in sunspot region 1520 taken in different colors or wavelengths of light. 

Sunspot region 1520 isn’t done yet. Space weather forecasters give it a moderate chance of producing more X-class flares through the 15th. Sunspots are regions on the sun’s surface where magnetic energy is highly concentrated. Flares occur when magnetic fields of opposite directions come into close contact within a sunspot group, interact with each other and release that energy explosively.

Yesterday’s flare shortly before it popped off (left) and during the explosion (right) seen in far ultraviolet light.  Credit: NASA

Light the fuse on 160 billion tons of TNT and you’ve got the equivalent of a solar flare. Flares heat the surrounding gases to 18 million degrees and eject matter into space as CMEs at speeds over 600 miles per second. Wicked!

Tomorrow morning (July 14) and Sunday morning, watch for beautiful pairings of the moon and planets Jupiter and Venus. Created with Stellarium

The weekend’s shaping up to be a not-to-miss potpourri of celestial enjoyments. Tomorrow morning the moon moves closer to the sky’s current brightest planets Jupiter and Venus in the company of the sky’s two brightest star clusters – the Pleiades (Seven Sisters) and Hyades. Watch for them in the east starting around 3:30 a.m. as morning twilight is just beginning. They’ll be higher and easier to see an hour later, but the brightening sky may may require binoculars to see the clusters.

The BIG EVENT happens the next morning on Sunday the 15th, when the moon will be in conjunction and near both planets at dawn. Should be a wonderful sight. Get your cameras ready for both the conjunction and northern lights.

Interplanetary magnetic field cracks open an auroral portal

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Pale green auroral patches and rayed arcs illuminate the bottom third of the northern sky earlier this morning. Photo: Bob King

Another bleary-eyed morning with a happy heart. So it is after a late-night encounter with the northern lights. Last night’s display wasn’t in the forecast but just one of those things that happens time to time, when the interplanetary magnetic field dips southward.

Auroras bloom in Earth’s skies for at least several reasons: solar flares, coronal mass ejections, coronal holes AND fluctuations in the sun’s magnetic field.

The spiral shaped IMF, invisible to the eye, permeates the solar system with the sun’s magnetic field. Credit: NASA with my own additions

Streams of high-speed electrons and protons, known as the solar wind, boil off the sun, spreading its magnetic field across the solar system.

Called the interplanetary magnetic field or IMF, it continually rushes past Earth and the rest of the planets like waves flowing around rocks in a pond.

With one difference. Since the sun rotates, the IMF and solar wind are twisted into a spiral. Picture the IMF as water spraying from a rotating lawn sprinkler.

Earth has a magnetic field too. While it deflects most of what the sun deals out,  it’s not without its vulnerabilities or “soft spots”. When the gusty, ever-fluctuating IMF tips south in the Earth’s vicinity, it cancels our magnetic field at the point of contact, opening a crack in the planet’s armor. Solar wind particles seize the opportunity and stream directly into the upper atmosphere to spark auroras.  That’s what happened last night. Thank you IMF.

Look at this beast! Sunspot group 1520, seen this morning July 9, has a complex magnetic field, making it a potential hotbed of solar flares in the coming weeks. It’s also big enough to see with the naked eye using a safe solar filter. For timely aurora alerts, follow my tweets at AstroBob_bk. Credit: NASA

There’s a small chance for auroras again tonight from a coronal mass ejection blasted our way by last week’s large sunspot group 1515, now departing over the sun’s western edge. A worthy replacement has already sprung up along the sun’s eastern edge, the behemoth group numbered 1520. I easily spotted it this morning with nothing more than a pair of solar eclipse glasses. The sketch below shows how it looked facing east around 10:30.

Sketch of naked eye sunspot group 1520

Last night I grabbed another look at Nova Sagittarii No. 4, the topic of yesterday’s blog. I hope you did too. The star was faintly visible at magnitude 8.2 in 10×50 binoculars from a dark site. For the moment, it’s fading after its initial outburst – typical nova behavior – but keep an eye out for surprises. Novae sometimes re-brighten on their way back to obscurity.

While you’re up late squinting after auroras, don’t miss the last quarter moon rising around midnight in Pisces. It’s on its way to a wonderful conjunction with Jupiter and Venus this Sunday.

A necklace for your Milky Way and a giant sunspot

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This past Wednesday night I dashed off to our local planetarium with zip drive in hand to give a PowerPoint presentation on black holes, but when I arrived, one of the student staffers there gave me a funny look. “Your show’s not till next Wednesday,” she said smiling.

The Necklace Nebula is a planetary nebula 15,000 light years away in the constellation Sagitta near the Northern Cross. The bright knots that resemble jewels in a necklace are dense, glowing pockets of gas. Credit: NASA / ESA

A bonehead move on my part, but two good things came from my error. The first was the sense of relief at now having a show done a full week in advance, a record for me. The second involved my younger daughter Maria. She had dropped by to say ‘hi’ and brought me a candy bar -  a Milky Way, naturally.

One sweet gesture deserves another, so Maria today I offer you the Necklace Nebula as thanks. This pretty bauble resides in the little constellation of Sagitta the Arrow not far from the Northern Cross. A pair of closely-orbiting stars worked in tandem to create the nebula beginning about 10,000 years ago. That’s when the larger, more evolved star bloated up and engulfed its companion. Amazingly, the smaller star remained intact as it orbited inside the giant. Over time the littler one transferred some of its orbital energy to the bigger star which sped up in response. Powerful centrifugal forces caused the big one to slough off  gas along its equator in the form of a ring. The jewels on the necklace are especially dense blobs of gas.

The two stars are only a few million miles apart and appear as a single star in the photo. The innermost planet Mercury’s otherwise rapid 88-day orbital period seems glacial compared to the one day it takes for these two stars to revolve about each other.

The huge sunspot at right, photographed this morning by NASA's Solar Dynamics Observatory (SDO), covers an area 17 times the size of Earth. Credit: SDO/NASA

Speaking of stars, the home star’s cooked up a monster sunspot, one of the biggest in years. Over the past several days, Region 1339 has rotated around the sun’s eastern edge and looks ripe for big flares in the days ahead. One significant flare occurred Thursday but it was not directed toward our planet. We’ll keep a watch on this one as it rotates closer to the sun’s center and alert you when Earth-directed activity might lead to a northern lights show. For the moment, space weather forecasters are calling for a small possibility of an auroral storm for today due to unrelated effects from a coronal hole. Check the latest HERE.

Complex magnetic fields create gigantic loops in the hot plasma above the giant sunspot at left. Photo taken in UV light during yesterday's flare by SDO. Credit: NASA/SDO

Sun grows a monster spot

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Sunspot region 1302 is bursting with activity including two large X-class flares late last week. Its busy magnetic configuration makes more large flares likely this week. The group is larger than the planet Jupiter. Credit: NASA/SDO

I just got in from observing the sun with my little refracting telescope. My attention was riveted by a huge sunspot group on the eastern half of the sun’s disk that’s been growing larger and feistier by the day. I even saw it without any telescope at all through a pair of safe filtered glasses. Naked-eye sunspots you can see from your own front yard are uncommon and quicken the pulse of any solar observer.

I use a basic 80mm (3-inch) refracting telescope equipped with a safe reflective glass solar filter to quick and easy views of the sun. Photo: Bob King

Solar weather forecasters with NOAA’s Space Weather Prediction Center are calling for minor to major magnetic storms from a coronal mass ejection (CME) associated with a hefty flare from the group that popped off on the 24th. In basic English, that means there’s a possibility for auroras tonight across the northern U.S. and southern Canada. Because the spot group has a jumbled mix of north and south magnetic poles all within close proximity, chances are excellent that opposite poles will encounter one another and release powerful energy in the form of solar flares, increasing the chances for more northern lights in the coming week. And since the group is rotating closer to the center of the sun, any CMEs that occur are more likely to be directed toward Earth. ** UPDATE 9/26 at 11:30 p.m. — aurora is out over northern U.S.  Seen briefly in Duluth, Minn. before clouds moved in.

Sunspot region 1302 was an obvious dark dot this morning when viewed through solar filter glasses.

Timing couldn’t be better. The last modest auroral display was mostly washed out by  September’s full moon. This week the moon is now around new phase and won’t cause any problems. If you’re interested in observing the sun through your telescope, it’s essential to use a safe glass or optical mylar solar filter. These are available from a variety of vendors including Orion Telescopes. Wherever you purchase yours, make sure it’s the kind that fits over the front end of the telescope to ensure the safest filtration.

Inexpensive sun-viewing glasses use a safe black optical mylar for lenses. Photo: Bob King

If you don’t own a telescope but would like to follow the progress of naked eye sunspots like group 1302, check out the “eclipse shades” from Rainbow Symphony. The glasses are made of cardboard with a safe, quality optical filter that gives a crisp image of the sun.

Sun watching is fun, easy and very rewarding as you follow the day-by-day march of spot groups across the disk. Old ones fade and new spots can pop up overnight.

Is the sun about to chillax?

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A spectacular prominence along the sun's limb photographed on Monday. Prominences are large clouds of incandescent hydrogen gas held aloft by solar magnetic fields. Credit: John Chumack

You wouldn’t know it by looking at recent photos of the sun, but three lines of research indicate that solar activity has been slowing down for more than a decade. Sunspots and other magnetic activity that liven up the sun and produce auroral storms here on Earth follow an 11-year cycle. During the last maximum in 2000, spots and the solar flares they spawn were commonplace. After an unusually long minimum, our star is once again climbing out of its ‘magnetic hole’ toward the next maximum forecast for May 2013.

Despite the rise, scientists looking at trends in solar activity have noticed three significant changes in the sun’s output that could indicate an overall decline in the coming decades:

A large, new sunspot group just made its appearance along the east limb of the sun this week. This photo was taken earlier today by the Solar Dynamics Observatory. Credit: NASA

* Sunspots form when tubes of intense magnetism rise from beneath the surface and prevent the cooling solar gases from sinking back into the sun’s interior. Spots appear black because they’re several thousand degrees cooler than the surrounding regions. Matt Penn of the National Solar Observatory and colleagues used the McMath-Pierce Telescope at Kitt Peak in Arizona to measure sunspot magnetism over the past 13 years and discovered a continuous decline in field strength.

To give you a feel for magnetic strength, Earth’s magnetic field – the one that orients our compasses – measures less than 1 gauss at the planet’s surface.  Typical sunspots are in the 2,500-3,000 gauss range. Penn measured declines of 50 gauss per year. If the trend continues and sunspots’ strengths drop below 1,500 gauss, there won’t be enough magnetic energy for them to form. Hand in hand with the drop in magnetism, spots have also been getting hotter.

* Richard Altrock, manager of the Air Force’s coronal research program at Sunspot, New Mexico, used 40 years of measurements of the sun’s outer atmosphere or corona to discover that there’s less magnetic activity at the sun’s poles than in the past.

East-west moving jet streams inside the Sun migrate from the poles toward the equator during the solar cycle. At left (solar minimum) the red jet streams are located near the poles. At right (solar maximum) they have migrated close to the equator. The jet streams are believed to play an important role in generating the Sun's magnetic field and sunspots. Credit: National Solar Observatory, Air Force Research Laboratory

* Frank Hill and Rachel Howe of the National Solar Observatory at Sacramento Peak in New Mexico studied solar jet streams of magnetic energy flowing beneath the surface of the sun using helioseismology, a technique of analyzing sound waves emitted by the sun to divine its internal structure. The streams start at the poles at the beginning of cycle and work their way down to 22 degrees north and south latitudes, where they initiate a new round of solar activity.

The latest streams began their journey in 1996 but didn’t arrive at the 22 degree mark until 13 years later instead of the usual 11. This slower than normal speed is yet another indicator of depressed solar activity.

Temperature changes are shown in the northern hemisphere during the time of the Maunder Minimum. The deeper the shade of blue, the colder. Credit: Map adapted from Shindell et al., 2001, copyright AAAS 2001

All these signs point to a 2013 maximum that will be on the low side, followed by a delayed start in the next rise of solar activity around 2021. Some scientists even suspect the next cycle may not happen at all. If that’s the case, we might be in for a long, quiet spell of virtually no sunspots and flares. The last time this happened was in the latter half of the 17th century, a period of time called the Maunder Minimum. It coincided with unusually low temperatures and long winters across much of the northern hemisphere, and may have been related to a decline in sun’s ultraviolet light.

An active sun pours out more UV light. UV light acting on oxygen atoms in the upper atmosphere creates our planet’s ozone layer. Less ozone can alter the movements of those narrow, fast-moving air currents called jet streams, which in turn can redirect the paths taken by winter storms. It’s anyone’s guess whether another extended minimum might lead to global changes in weather patterns. You can read more about possible climate effects related to the Maunder Minimum HERE.

Several up sides to a solar magnetic downside would be a safer space environment for astronauts (fewer flares to worry about), less heating of the Earth’s outer atmosphere (causes it to expand and drag down orbiting satellites more quickly), and fewer threats from magnetic storms to the grids that supply our electricity. The downside: no sunspots, flares and auroras. We’ll have to wait and see, but after this last prolonged solar minimum, I’m ready for all the fun the sun can spin.

One last note. If you live in North America, you won’t be able to see today’s total lunar eclipse in the flesh, but several websites will be broadcasting it live this afternoon through about 5 p.m. Central time. Bad news is, I checked the three out I posted in yesterday’s blog and they’re clogged or not working, so please use this one out of Dubai, United Arab Emirates. The same feed is also at this YouTube link. The picture is fantastic and the moon looks awesome! Not only that but the live narration and guests add a lot to the presentation.

Aliens worlds both nearby and beautiful

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Symmetrical magnetic loops arc above a sunspot group just beyond the eastern edge of the sun in this photo taken today by the Solar Dynamics Observatory in the far ultraviolet light. Credit: NASA

A peek at the Solar Dynamics Observatory website today revealed a spectacular series of magnetic loops belonging to an active sunspot group just beyond the eastern limb of the sun. It will rotate over into view in the next few days, but we’re already getting a preview of it through glowing loops of gas bound up in the group’s magnetic field – similar to a sprinkling of iron filings that outline the magnetic field around a common magnet. The loops lie high in the sun’s atmosphere allowing us to glean the group’s presence beyond the limb.

The backside of the sun photographed by the STEREO 'behind sun' spacecraft late yesterday in ultraviolet light. The group with the loops is arrowed. Credit: NASA

The same group kicked out a spectacular CME or coronal mass ejection of material into space yesterday evening. Though not directed at the Earth, it hints at good things to come after a week of the doldrums. Aurora watchers look forward to any uptick in solar activity.

Tonight the moon reaches first quarter phase, so called because it’s traveled  a quarter the way around its orbit since new moon. First quarter is one of the best times for moon viewing because it’s conveniently placed high in the southern sky at sunset and doesn’t set till midnight. With the naked eye, you can see four or five large dark patches or lunar seas labeled in the photo above. The easiest ones, Serenity and Tranquillity, form the two eyes of the ‘man in the moon’ visible at full moon.

See if you can spot the dark patches or lunar seas on the first quarter moon. These are ancient lava-filled, impact basins created by asteroid bombardment 4 billion years ago. The lunar highlands (white area) are saturated with craters best seen near the lunar sunrise line (left) called the terminator. A = Sea of Serenity, B = Sea of Tranquillity, C = Sea of Crisis, D = Sea of Fertility and E = Sea of Nectar. Photo credit: John Chumack

7x and higher power binoculars will show a crinkly texture along the moon’s terminator created by the thousands of craters lit by low-angled sunlight there. If you’ve got steady hands, you may even be able to discern the outlines of the larger ones. Up near the top or north end of the moon, look for two rumpled, bumpy arcs. The larger one is the Apennine Mountain range which spans 370 miles with peaks rising to 3 miles high. To its north are the Caucasus Mountains.

Both are named after their earthly counterparts, but neither formed through plate tectonics like Earth’s mountain ranges. These are rings of lunar rock created during asteroid impacts long ago.

Telescopic observers will delight in all the craters and shadowy textural details that festoon the terminator at first quarter phase. Trust me, any scope will give you an eyeful tonight. Excellent crater and mountain viewing continues for the next several nights as the moon waxes toward gibbous phase.