Sunspots

From Tom DF5JL on the UDXF newsgroup:

The weekend was really good for surprises: Although solar wind speeds were low, the storms we observed were due to the enhanced magnetic field with sustained southward orientation associated with the passage of a magnetic cloud, which in turn coalesced with the 20th August coronal
mass ejection (CME). Negative Bz values were observed since about 1500 UT on August 25, and finally reached a value of -17nT.

Not only did a coronary mass ejection (CME) give us a magnetic strom of class G3 (k = 7), suddenly also a big sunspot appeared. We remember: For most of the year 2018, the solar disk was empty, without even the slightest sunspot. But this weekend suddenly there was a rapidly expanding spot with two dark cores as wide as the earth.

The new sunspot AR2720 is not only large, its magnetic polarity is also reversed compared to the sunspots of the current solar cycle 24. So, could this be the first big sunspot of the coming solar cycle? A new solar cycle always starts with a sunspot, in which magnetic north and south poles are reversed compared to the previous spots.

However, the relative equatorial proximity of this spot speaks against it - a sure sign of the beginning of a new cycle would be in addition to the reverse polarity of a relative equatorial distance. Further
observations are necessary.

As well as better conditions on the shortwave ;)

73 Tom DF5JL

X-Flare - Earth Facing

UPDATE, 3:30 p.m.: NOAA’s Space Weather Prediction Center (SWPC) just posted the following:

The R3 (Strong) Radio Blackout today at 12:49 EDT (1649 UTC) was accompanied by an earth-directed CME. Hampered by limited observations of the event, SWPC forecasters are now anticipating the passage of the [coronal mass ejection] around 1:00 a.m. EDT, Saturday, July 14. G1 (minor) Geomagnetic Storm activity is expected to then ensue through the rest of the day.

In short, NOAA is predicting minor effects from this space weather event - no major impacts on the power grid or satellites anticipated - although we remind you forecasting space weather is difficult and surprises are possible. Sky watchers in northern U.S. (and high latitudes) may have an opportunity to see aurora late Friday night into early Saturday morning.

Original story below . . .

X-FLARE! Big sunspot AR1520 unleashed an X1.4-class solar flare on July 12th at 1653 UT. Because the sunspot was directly facing Earth at the time of the blast, this is a geoeffective event. Stay tuned for updates about possible CMEs and radio blackouts.
NASA's Solar Dynamics Observatory recorded a flash of extreme ultraviolet radiation from the blast site.



The UV and X-ray pulse from the flare will have partially ionized Earth's upper atmosphere on the dayside of our planet, disturbing the normal propagation of radio signals. Watch the Realtime Space Weather Gallery for possible reports of sudden ionospheric disturbances and other effects.

Breaking News: X5 Flare

GEOMAGNETIC STORM UPDATE: A CME propelled toward Earth by this morning's X5-class solar flare is expected to reach our planet on March 8th at 0625 UT (+/- 7 hr). Analysts at the Goddard Space Weather Lab, who prepared the CME's forecast track, say the impact could spark a strong-to-severe geomagnetic storm. Sky watchers at all latitudes should be alert for auroras.

Biggest Slar Flare in 4 years -- X-7

The Aug 9, 2011 eruption on the Sun that produced a X-7 class flare caused a temporary blackout of high frequency radio transmissions on the side of Earth covered in daylight. Navigation signals can be degraded in these instances. Credit: NASA/SDO/SOHO/Music: John Serrie

Researchers Crack the Mystery of the Missing Sunspots

Maybe we finally have some answers to the prolonged Solar Cycle 23 minimum. Below is from the NASA Science website relased this afternoon.

When solar activity recently plunged into a century-class minimum, many experts were puzzled. Now a group of researchers say they have cracked the mystery of the missing sunspots. Read the full story at http://science.nasa.gov/science-news/science-at-nasa/2011/02mar_spotlesssun/

Space weather team readies for upcoming solar max

Staff Sgt. Matthew Money monitors the near earth space environment at the 2nd Weather Squadron's space weather operations center located inside the Air Force Weather Agency at Offutt Air Force Base, Neb. The sun's last solar maximum occurred in 2000 and therefore it is expected to awaken from its current solar minimum and get more and more active this year. Sergeant Money is a forecaster with the 2nd WS space weather flight. (U.S. Air Force photo/Josh Plueger)

by Ryan Hansen, 55th Wing Public Affairs

OFFUTT AIR FORCE BASE, Neb. (AFNS) -- Solar max may sound like the name of a super hero, but it's certainly no comic book or 3-D movie.

Solar max is actually the name for the sun's most active period in the solar cycle, consistently producing solar emissions, solar flares and sun spots.

For a little background on the sun's activities, the star goes through roughly 11-year cycles of where it is very active and also relatively calm.

The sun's last solar maximum occurred in 2000 and it is expected to awaken from its current solar minimum and get more active this year.

According to the members of the 2nd Weather Squadron, an active sun can cause all sorts of problems for us.

"Solar weather plays a huge part in the warfighter's mission," said Staff Sgt. Matthew Money, a forecaster with the space weather flight. "Impacts from solar weather can cause radio blackouts, satellite communication failure, satellite orbit changes, satellite surface charging, or short circuits, and radar clutter."

That is why the squadron's worldwide space weather team of roughly 50 active-duty members, civilians and contractors continually analyze, forecast and provide alert notifications for the entire Department of Defense, as well as a slew of other government agencies.

"When space weather causes impacts to earth that meet or exceed warning thresholds our end users are informed within minutes," said Staff Sgt. Jonathan Lash, space weather flight forecaster.

"We send out warning bulletins through a computerized distribution system, (and) we have other graphical products that show what happened in the past six hours around the globe as well as what we expect to happen in the upcoming six hours," he said.

Members of the 2nd WS rely on five ground-based solar observatories as well as a network of satellites orbiting the earth, to accomplish their mission.

"There aren't too many opportunities to be the Air Force's sole provider of something," said Lt. Col. Jim Jones, 2nd WS commander. "In this case, the mission is unique to the entire DOD."

Solar observatories are strategically placed around the globe in such places as Australia, Hawaii, Italy, Massachusetts and New Mexico. They include both optical and radio telescopes and ensure the squadron always has one eye, or ear, on the sun.

"The optical telescope network monitors solar surface features," said Master Sgt. Shane McIntire, the space weather flight chief. "It automatically tracks the sun and directs light to the instruments, which collect data and are controlled by computers. It scans specific regions at a rate of at least twice per minute."

Through filtered lenses space weather analysts are able to perform flare patrol and view sunspots to determine the magnetic complexity of the region.

"The telescope has special filters that isolate a single optical wavelength," said Master Sgt. Shane Siebert, who leads Det. 4's solar observatory for the 2nd WS at Holloman Air Force Base, N.M.

"This wavelength, 6563 angstroms, is called hydrogen alpha, or H-Alpha, and is where the majority of solar activity occurs," he said. "Analysts monitor this wavelength from sunrise to sunset, and are looking for specific signatures that may lead to solar flares and other adverse activity."

But not all of the sun's activities can be captured using optical telescopes. Some events have a unique radio-frequency signature that can also be measured.

Using a mixture of technology from the 1970s to the present, radio observatories are able to monitor frequencies in the 25-180 megahertz range, as well as eight other discrete frequencies. Their digitized output is collected by a computer and then processed and analyzed for solar activity.

"We actually are able to detect the specific strength at a given radio frequency," said Maj. Bradley Harbaugh, who commands Det. 5's solar observatory for the 2nd WS at Palehua, Hawaii. "What we detect are energetic solar emissions in (specific) frequency bands or ranges. When detected, we (are able to describe) the start time, duration, intensity and type of solar emission. This helps describe the potential impacts by identifying the characteristics of what may impact earth."

Identifying these solar emissions is crucial to the warfighter's communication abilities.

"If there is solar energy that increases on your frequency, you can try to talk into your radio, but the noise from the sun will be stronger than your transmission, therefore drowning out what you are saying," Major Harbaugh said. "As an operator, you can increase your radio power to try and 'out-broadcast' the sun, but you are also now broadcasting over a much larger area, making your transmission more susceptible to enemy detection. Therefore, the sun's impact must be a consideration when planning a mission."

The squadron's network of satellites includes those owned and operated by the DOD, NASA and the National Oceanic and Atmospheric Administration. They include a combination of systems that are both dedicated solely to space weather as well as a few that utilize space weather sensors.

"We gather a significant amount of data from satellites," Sergeant McIntire said. "Imagery from (satellites) can augment the ground-based network, providing real-time monitoring of solar features at wavelengths that can't be seen from the ground."

Data from all of these sources combined are continually pushed to the space weather operations center at the Air Force Weather Agency here. With this information in hand, the squadron can produce the most reliable space weather forecast possible.

However, even with all of this data, producing a space weather forecast is still much more difficult than creating one for terrestrial weather.

"Space weather is a terribly difficult science and it takes a lot of training and experience," Colonel Jones said.

"Space weather forecasting is very reactive," Sergeant Money said. "The knowledge and tools are not quite up to par in order to do accurate forecasting like we do here on Earth."

It is also important to note that today the world is much more reliant on space-based assets than they were during the last solar max, officials said. With cellular phones, portable navigation devices and satellite television receivers all part of our daily lives, a huge solar weather event could wreak havoc on quite a few different platforms.

"The impact of a solar storm in 2000 was probably not as great, due to the lower density of space technology, and the limited number of consumers utilizing the data," Major Harbaugh said. "However, the ripple from a major solar event now will more likely be felt across a much broader consumer base, the public, since there are many more assets and many more users of space data."

However, with improved technology and an increased knowledge of the sun's activities, the squadron is more prepared than ever for the upcoming solar max, Colonel Jones said.

"Since the last solar max, we've upgraded most of our numerical models in terms of both their basic science and the data they ingest," he said. "That's a direct result of the advances in sensors and the technology that enables rapid data transfer. We can react faster and see farther than ever before."

"We already have members within the unit developing forecast techniques based on signatures we see on the sensors," Sergeant Money said.

So it's a safe bet that the next couple of years will be hectic for the 2nd WS. Their mission to provide situational awareness to key decision makers will certainly keep them busy.

"In the last month alone, we've had (more than 30) reportable energy events," Major Harbaugh said. "The workload has already increased and will continue to do so for probably the next year or two."

"About a year ago, it was not uncommon for an analyst to only have one very small region of the sun to monitor," Sergeant Siebert said. "Today, it is normal for analysts to keep fairly busy monitoring four-to-six regions.

"Studies of the last solar max show that a typical day included 22 active regions, almost four times our current workload," he added.

Regardless, the squadron's space weather analysts, forecasters and technicians around the globe are ready for the sun's upcoming fury, Colonel Jones said

Active Geomagnetic Activity Due at Any Time

The first interplanetary shock, driven by the CME from Sunday, is expected any time. Soon thereafter, the shock from Monday evening's R3/CME is due. Look for G1-G2 (and maybe periods of G3 if the following shock compresses and enhances the CME magnetic field). Geomagnetic storming should persist 24- 48 hours. Back at the Sun, Region 1158 is still hot and fast-growing, Region 1161 is producing small flares.

M1.4 Magnitude X-ray Flare 28 January 2011

From: "Tomas Hood (NW7US)"

At 0104 UTC, 28 January 2011, an X-ray flare with a flux magnitude of M1.4 erupted, unleasing a coronal mass ejection. The associated coronal mass ejection was not directed toward Earth, so it will not affect radio propagation at all. The only affect was the immediate (within eight minutes) where there was a short-lived Sudden Ionospheric Disturbance on lower frequencies, and, there was also a Type II radio burst (a rushing wind sound on HF).

The source of the eruption was the active sunspot region 11149 (and possibly involved the region 11147, which is north of 11149). These have now rotated out of view from Earth. That's why the CME is not heading our way. it erupted out into space away from us.

Here are a few movies I've posted:

The actual flare and CME as seen at the 304 Angstrom wavelength:
http://www.youtube.com/watch?v=hMCgrJWTtR0

The CME as seen by LASCO C2: http://www.youtube.com/watch?v=Q1diDvKgqtw

The active Sunspot regions 11147 and 11149, showing flares and surges prior to the M1.4 Magnitude flare: http://www.youtube.com/watch?v=dW2IgXy53U0

--
73 de NW7US,

Tomas David Hood
Hamilton, Montana

http://nw7us.us/
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http://sunspotwatch.com/

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Thunderstorms Make Antimatter

Could this be the vehicle that creates the e-skip we use in the late Spring and Summer for VHF (10 meter and above) skip. Sure is an intriguing thought.

http://science.nasa.gov/science-news/science-at-nasa/2010/11jan_antimatter/

Scientists using NASA's Fermi Gamma-ray Space Telescope have detected beams of antimatter produced above thunderstorms on Earth, a phenomenon never seen before.

Scientists think the antimatter particles were formed inside thunderstorms in a terrestrial gamma-ray flash (TGF) associated with lightning. It is estimated that about 500 TGFs occur daily worldwide, but most go undetected.

"These signals are the first direct evidence that thunderstorms make antimatter particle beams," said Michael Briggs, a member of Fermi's Gamma-ray Burst Monitor (GBM) team at the University of Alabama in Huntsville (UAH). He presented the findings Monday, during a news briefing at the American Astronomical Society meeting in Seattle.

Fermi is designed to monitor gamma rays, the highest energy form of light. When antimatter striking Fermi collides with a particle of normal matter, both particles immediately are annihilated and transformed into gamma rays. The GBM has detected gamma rays with energies of 511,000 electron volts, a signal indicating an electron has met its antimatter counterpart, a positron.

Although Fermi's GBM is designed to observe high-energy events in the universe, it's also providing valuable insights into this strange phenomenon. The GBM constantly monitors the entire celestial sky above and the Earth below. The GBM team has identified 130 TGFs since Fermi's launch in 2008.

"In orbit for less than three years, the Fermi mission has proven to be an amazing tool to probe the universe. Now we learn that it can discover mysteries much, much closer to home," said Ilana Harrus, Fermi program scientist at NASA Headquarters in Washington.

The spacecraft was located immediately above a thunderstorm for most of the observed TGFs, but in four cases, storms were far from Fermi. In addition, lightning-generated radio signals detected by a global monitoring network indicated the only lightning at the time was hundreds or more miles away. During one TGF, which occurred on Dec. 14, 2009, Fermi was located over Egypt. But the active storm was in Zambia, some 2,800 miles to the south. The distant storm was below Fermi's horizon, so any gamma rays it produced could not have been detected.

"Even though Fermi couldn't see the storm, the spacecraft nevertheless was magnetically connected to it," said Joseph Dwyer at the Florida Institute of Technology in Melbourne, Fla. "The TGF produced high-speed electrons and positrons, which then rode up Earth's magnetic field to strike the spacecraft."

The beam continued past Fermi, reached a location, known as a mirror point, where its motion was reversed, and then hit the spacecraft a second time just 23 milliseconds later. Each time, positrons in the beam collided with electrons in the spacecraft. The particles annihilated each other, emitting gamma rays detected by Fermi's GBM.

Scientists long have suspected TGFs arise from the strong electric fields near the tops of thunderstorms. Under the right conditions, they say, the field becomes strong enough that it drives an upward avalanche of electrons. Reaching speeds nearly as fast as light, the high-energy electrons give off gamma rays when they're deflected by air molecules. Normally, these gamma rays are detected as a TGF.

But the cascading electrons produce so many gamma rays that they blast electrons and positrons clear out of the atmosphere. This happens when the gamma-ray energy transforms into a pair of particles: an electron and a positron. It's these particles that reach Fermi's orbit.

The detection of positrons shows many high-energy particles are being ejected from the atmosphere. In fact, scientists now think that all TGFs emit electron/positron beams. A paper on the findings has been accepted for publication in Geophysical Research Letters.

"The Fermi results put us a step closer to understanding how TGFs work," said Steven Cummer at Duke University. "We still have to figure out what is special about these storms and the precise role lightning plays in the process."

Editor: Dr. Tony Phillips | Credit: Science@NASA

Propagation Alert: Will it hit Earth?

On August 1, 2010, the Solar Dynamics Observatory (SDO) observed a beautiful prominence eruption that may hit Earth and cause a geomagnetic storm. As the solar cycle progresses and the Sun becomes more active there will be many more opportunities to observe the causes of space weather. Want to see what happens? Follow the event at spaceweather.com.

And from the Spaceweather website:

On August 1st, the entire Earth-facing side of the sun erupted in a tumult of activity. There was a C3-class solar flare, a solar tsunami, multiple filaments of magnetism lifting off the stellar surface, large-scale shaking of the solar corona, radio bursts, a coronal mass ejection and more.

High-latitude sky watchers should be alert for auroras tonight. One and possibly two coronal mass ejections (CMEs) are heading toward Earth, propelled by the solar eruptions of August 1st (see below). NOAA forecasters estimate a 10% chance of major geomagnetic storms and a 45% chance of at least some geomagnetic activity when the clouds arrive on August 3rd and 4th.

And finally this report from our good friend Tomas Hood

At approximately 0855 UTC on August 1, 2010, a C3.2 magnitude soft X-ray flare erupted from NOAA Active Sunspot Region 11092 (1092).

At nearly the same time, a massive filament eruption occurred. Prior to the filament's eruption, NASA's Solar Dynamics Observatory (SDO) Atmospheric Imaging Assembly (AIA) instruments revealed an enormous plasma filament stretching across the sun's northern hemisphere. When the solar shock wave triggered by the C3.2-class X-ray explosion plowed through this filament, it appears to have caused the filament to erupt, sending out a huge plasma cloud (a coronal mass ejection, or CME).

A shock wave can be seen emerging from the origin of the X-ray flare and sweeping across the sun's northern hemisphere into the filament field. The impact of this shock wave may well have propelled the filament into space. The movies (see links, below) seem to support the conclusion that both eruptions, occurring together, are linked, despite the approximately 400,000 kilometer distance between the flare and the filament eruption. How can this be? While we cannot always see the magnetic field lines between solar features (magnetic field lines are not visible unless there is plasma trapped along these field lines), we can assume from this event
that huge connecting field lines existed between the sunspot region and the filament in the sun's northern hemisphere.

This is an amazing event. A complex series of eruptions involving most of the visible surface of the sun has occurred, ejecting plasma toward the Earth. This coronal mass ejection (CME) rides the solar wind. Depending on the speed of the solar wind and the ejected plasma, this cloud will reach Earth's magnetosphere sometime between August 3 and August 5. High-latitude sky watchers should be alert for auroras. Radio communications by way of the ionosphere may become degraded soon after the CME arrives, and the degraded conditions may last for up to three days.

First view at the 304-Angstrom wavelength by SDO/AIA:
http://www.youtube.com/watch?v=VyaqxKkSCpU

Second view at the 171-Angstrom wavelength by SDO/AIA:
http://www.youtube.com/watch?v=HW_-yQY6YlA

Source: SDO/AIA

73 de NW7US, Tomas David Hood ( http://tomas-david-hood.com/ )

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Linux User #32405 - Since 1996

Yet Another New Solar Cycle 24 Sunspot Group

Posted Sunday November 15, 2009 at http://www.wcflunatall.com/nz4o4.htm

Yesterday yet another solar cycle 24 sunspot group emerged, this time in the NE quadrant of the Sun near N29E35. As of yet it has not received a number by SIDC Belgium or NOAA/SWPC. If numbered by NOAA/SWPC it would receive #11031.

This new sunspot group pushed the solar flux index (SFI) to 75.9 yesterday and could push the SFI above 80 in coming days. This would raise the maximum usable frequency (MUF) of the F layer high enough to improve propagation conditions on 20, 17 and 15 meters.

Under the very old method of counting sunspots SIDC Belgium gave the sunspot group a number of 11. But in reality only one simple sunspot actually emerged.

The solar cycle 24 sunspot group that emerged on Friday November 13, 2009 that received SIDC Belgium Catania #25 and located in the SW quadrant of the Sun has faded, with it's remnant Plage currently setting around the west limb of the Sun. It did not receive #11031 by NOAA/SWPC.

Also yesterday old solar cycle 24 sunspot group #11029 rose above the east limb of the Sun but is only a large Plage with no sunspots. Last month #11029 made it's debut as the largest and most active sunspot group in fledgling solar cycle 24.

73 & GUD DX,
Thomas F. Giella, NZ4O
Lakeland, FL, USA
nz4o@arrl.net
eList Owner/Moderator

COL LF/MF/HF/VHF/UHF Frequency Radiowave Propagation Email Reflector:
http://lists.contesting.com/mailman/listinfo/spaceweather
NZ4O Daily Solar Space Weather & Geomagnetic Data Archive:
http://www.wcflunatall.com/nz4o1.htm
NZ4O Solar Space Weather & Geomagnetic Data In Graphic & Image Format:
http://www.wcflunatall.com/nz4o2.htm
NZ4O Daily LF/MF/HF/6M Frequency Radiowave Propagation Forecast & Archive:
http://www.wcflunatall.com/nz4o3.htm
NZ4O Solar Cycle 24 Forecast Discussion & Archive:
http://www.wcflunatall.com/nz4o4.htm
NZ4O 160 Meter Radio Propagation Theory Notes:
http://www.wcflunatall.com/nz4o5.htm
NZ4O Solar Space Weather & Geomagnetic Raw Forecast Data Links:
http://www.wcflunatall.com/nz4o6.htm
Florida & U.S. Raw Weather Forecasting Resource Links:
http://www.wcflunatall.com/kn4lf13.htm

10.7-cm flux - highest yet in current Sunspot Cycle 24

It just keeps getting better! During the CQ WW Contest weekend, the solar flux climbed into the upper 70's. But, as this week unfolds, the flux climbs, with a current flux of 81! This is the highest recording yet since the first observed "new cycle sunspot" in January 2008, the "official" visual start of Sunspot Cycle 24. (We'll see where the statistical averaged solar minimum actually occurs).

Speaking of... the monthly observed smoothed count of zero, recorded in August, does not make that the statistical lowest point in the moving average, because the months prior, and the months since, have higher numbers. And, these numbers, except for August, are all increasing, each month. The current sunspot activity is further confirmation that this cycle is, albeit slow, alive and increasing in activity.

DX was great over the weekend. Even 15 meters was hot with activity. This week is one to enjoy - the CME and Flare activity continues to be low to at most moderate, leaving the geomagnetic field mostly stable. This results in fairly normal (non-depressed) ionospheric conditions.

Please feel free to post your observations of conditions on HF, this week. It would be very enlightening to hear how conditions really are, in your location. Please post your grid square / location, along with the report of working conditions and results of your activity.

This is an exciting start to the Autumn DX season!

--
73 de NW7US, Tomas David Hood - Bitterroot Valley of Montana

Singer/Songwriter/Guitarist : http://tomasdavidhood.com

Contributing editor: CQ Magazine, CQ VHF, Popular Communications, Monitoring Times magazine

Best Solar Prop Shop on the Net

If you are looking for the latest and greatest propagation and solar information I highly recommend the Solarcycle24.com website. VE3EN has put together some of the best web solar and propagation information sources onto one webpage for use by the radio hobby community.

If you are involved in the radio hobby and are advanced enough to know, use and understand how propagation works, then this site is a must visit and bookmark. I use it everyday. Go to http://www.solarcycle24.com/.

Are Sunspots Disappearing?

Another day with a spotless sun.

Author: Dr. Tony Phillips | Credit: Science@NASA

The sun is in the pits of the deepest solar minimum in nearly a century. Weeks and sometimes whole months go by without even a single tiny sunspot. The quiet has dragged out for more than two years, prompting some observers to wonder, are sunspots disappearing?

"Personally, I'm betting that sunspots are coming back," says researcher Matt Penn of the National Solar Observatory (NSO) in Tucson, Arizona. But, he allows, "there is some evidence that they won't."

Penn's colleague Bill Livingston of the NSO has been measuring the magnetic fields of sunspots for the past 17 years, and he has found a remarkable trend. Sunspot magnetism is on the decline.

"Sunspot magnetic fields are dropping by about 50 gauss per year," says Penn. "If we extrapolate this trend into the future, sunspots could completely vanish around the year 2015."

This disappearing act is possible because sunspots are made of magnetism. The "firmament" of a sunspot is not matter but rather a strong magnetic field that appears dark because it blocks the upflow of heat from the sun's interior. If Earth lost its magnetic field, the solid planet would remain intact, but if a sunspot loses its magnetism, it ceases to exist.

"According to our measurements, sunspots seem to form only if the magnetic field is stronger than about 1500 gauss," says Livingston. "If the current trend continues, we'll hit that threshold in the near future, and solar magnetic fields would become too weak to form sunspots."

"This work has caused a sensation in the field of solar physics," comments NASA sunspot expert David Hathaway, who is not directly involved in the research. "It's controversial stuff."

The controversy is not about the data. "We know Livingston and Penn are excellent observers," says Hathaway. "The trend that they have discovered appears to be real." The part colleagues have trouble believing is the extrapolation. Hathaway notes that most of their data were taken after the maximum of Solar Cycle 23 (2000-2002) when sunspot activity naturally began to decline. "The drop in magnetic fields could be a normal aspect of the solar cycle and not a sign that sunspots are permanently vanishing."

Penn himself wonders about these points. "Our technique is relatively new and the data stretches back in time only 17 years. We could be observing a temporary downturn that will reverse itself."

The technique they're using was pioneered by Livingston at the McMath-Pierce solar telescope near Tucson. He looks at a spectral line emitted by iron atoms in the sun's atmosphere. Sunspot magnetic fields cause the line to split in two—an effect called "Zeeman splitting" after Dutch physicist Pieter Zeeman who discovered the phenomenon in the 19th century. The size of the split reveals the intensity of the magnetism.

Astronomers have been measuring sunspot magnetic fields in this general way for nearly a century, but Livingston added a twist. While most researchers measure the splitting of spectral lines in the visible part of the sun's spectrum, Livingston decided to try an infra-red spectral line. Infrared lines are much more sensitive to the Zeeman effect and provide more accurate answers. Also, he dedicated himself to measuring a large number of sunspots—more than 900 between 1998 and 2005 alone. The combination of accuracy and numbers revealed the downturn.

If sunspots do go away, it wouldn't be the first time. In the 17th century, the sun plunged into a 70-year period of spotlessness known as the Maunder Minimum that still baffles scientists. The sunspot drought began in 1645 and lasted until 1715; during that time, some of the best astronomers in history (e.g., Cassini) monitored the sun and failed to count more than a few dozen sunspots per year, compared to the usual thousands.

"Whether [the current downturn] is an omen of long-term sunspot decline, analogous to the Maunder Minimum, remains to be seen," Livingston and Penn caution in a recent issue of EOS. "Other indications of solar activity suggest that sunspots must return in earnest within the next year."

Whatever happens, notes Hathaway, "the sun is behaving in an interesting way and I believe we're about to learn something new."

Spotless Sun: Blankest Year of the Space Age

Astronomers who count sunspots have announced that 2008 is now the "blankest year" of the Space Age.

As of Sept. 27, 2008, the sun had been blank, i.e., had no visible sunspots, on 200 days of the year. To find a year with more blank suns, you have to go back to 1954, three years before the launch of Sputnik, when the sun was blank 241 times.

FULL STORY at
http://science.nasa.gov/headlines/y2008/30sep_blankyear.htm?list1066509

This is what a spotless sun looks like.

Is a New Solar Cycle Beginning?

By Dr. Tony Phillips courtesy of Science@NASA

The solar physics community is abuzz this week. No, there haven't been any great eruptions or solar storms. The source of the excitement is a modest knot of magnetism that popped over the sun's eastern limb on Dec. 11th, pictured below in a pair of images from the orbiting Solar and Heliospheric Observatory (SOHO).

It may not look like much, but "this patch of magnetism could be a sign of the next solar cycle," says solar physicist David Hathaway of the Marshall Space Flight Center.

Above: From SOHO, a UV-wavelength image of the sun and a map showing positive (white) and negative (black) magnetic polarities. The new high-latitude active region is magnetically reversed, marking it as a harbinger of a new solar cycle.

For more than a year, the sun has been experiencing a lull in activity, marking the end of Solar Cycle 23, which peaked with many furious storms in 2000--2003. "Solar minimum is upon us," he says.

The big question now is, when will the next solar cycle begin?

It could be starting now.

"New solar cycles always begin with a high-latitude, reversed polarity sunspot," explains Hathaway. "Reversed polarity " means a sunspot with opposite magnetic polarity compared to sunspots from the previous solar cycle. "High-latitude" refers to the sun's grid of latitude and longitude. Old cycle spots congregate near the sun's equator. New cycle spots appear higher, around 25 or 30 degrees latitude.

The region that appeared on Dec. 11th fits both these criteria. It is high latitude (24 degrees N) and magnetically reversed. Just one problem: There is no sunspot. So far the region is just a bright knot of magnetic fields. If, however, these fields coalesce into a dark sunspot, scientists are ready to announce that Solar Cycle 24 has officially begun.

Below: Solar Cycle 23 is coming to an end. What's next? Image credit: NOAA/Space Weather Prediction Center.



Many forecasters believe Solar Cycle 24 will be big and intense. Peaking in 2011 or 2012, the cycle to come could have significant impacts on telecommunications, air traffic, power grids and GPS systems. (And don't forget the Northern Lights!) In this age of satellites and cell phones, the next solar cycle could make itself felt as never before.

The furious storms won't start right away, however. Solar cycles usually take a few years to build to a frenzy and Cycle 24 will be no exception. "We still have some quiet times ahead," says Hathaway.

Meanwhile, all eyes are on a promising little active region. Will it become the first sunspot of a new solar cycle? Stay tuned for updates from Science@NASA.

First 40 MHz Amateur Radio Propagation Beacon On The Air

For VHF amateur radio operators and scanner enthusiasts this beacon could be a great propagation tool. Thanks to QRZ.com, M5AKA, AA7BQ, and Mark KB4CVN for passing this tidbit along.

Ivan OZ7IS has announced that the first 40 MHz Amateur Radio propagation beacon OZ7IGY is now on the air on 40.021 MHz

Background:
The European Radiocommunications Office (ERO – now ERC) of the CEPT launched in March 1993 Phase II of a Detailed Spectrum Investigation (DSI) covering the frequency range 29.7 - 960 MHz.

The results were presented to Administrations in March 1995 with the objective of facilitating a European Table of Frequency Allocations and Utilisations to be implemented by the year 2008.

Regarding the Amateur Radio Service the DSI Management Team recommended (among other things) that 70 MHz to be considered as an amateur band AND: “frequencies in the vicinity of 40.680 MHz be considered for amateur propagation beacons.”

During the IARU, Region 1, C5 meeting in Vienna earlier this year David, G4ASR, told that the RSGB were planning such a 40 MHz beacon. I promised him to take a similar initiative when returning to Denmark.

In July the GB3RAL 40.050 and 60.050 MHz VHF beacons were approved and shortly after OZ7IGY received the permit to operate on 40.021 MHz.

On 26th of July (after paying the licence fee) at 18.20 UTC OZ7IGY became operational on:

40.021 MHz near Jystrup (Ringsted), JO55wm, 97 masl / 5 magl. The antenna is a dipole heading 255 / 75 degrees. Will shortly be changed to a Turnstile (X-dipole). The output to the antenna is 22 Watt keying in F1A (frequency Shift Keying) according to the IARU, Region 1, standard. 250 Hz shift.

The “licence” is valid for a year and the results of the experiments are to be reported to the ITST.

The “licence” is “experimental” on a non-inteference basis and will not create a precedent for any other kind of amateur radio activities in this part of the spectrum!

Please report to DX-summit whenever you hear the beacon. Then we can collect data for the report to ITST and may be able to argue for a renewal of the licence next year?

In 1993 the head of ERO was David Court, EI3IO (G3SDL, OZ3SDL etc….) I have a feeling that without his “stamp” on the DSI report we would not have had the ever increasing access to 70 MHz throughout Europe or these 40 MHz amateur propagation beacons!

Vy 73 de OZ7IS, Ivan - Email: oz7is at qrz.dk
Beaconkeeper – OZ7IGY - http://www.oz7igy.dk/

Related URLs :

GB3RAL now licenced for 40 and 60 MHz (7th July) http://www.southgatearc.org/news/july2007/gb3ral.htm

Denmark to get 40 MHz beacon (19th July) http://www.southgatearc.org/news/july2007/danish_40mhz_beacon.htm