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hamrodforu

Posts: 12 Member Since:02/23/10

#21 [url]

Feb 23 10 12:56 PM

The spots are storms on the superhot Sun and they are keeping Earth aglow, according to the U.S. space agency.

Noting that the Sun is especially hot right now, NASA says our star is spewing out electromagnetic radiation in the midst of an interesting storm season. A lot of that energy arrives at Earth.

However, even as plasma and high-energy particles from the Sun light up Earth's ionosphere, orbiting detectors and other scientific equipment compose an early-warning system help us keep satellites in space and power grids on the surface of the planet safe.

Solar Cycles. Sunspots can be seen to vary on the face of the Sun in eleven-year actvity cycles. They have been watched for centuries, but only recently have scientists understood that they eject hot electromagnetic plasma.

NOTE: you never should look directly at the Sun for any reason. Doing so can damage your eyesight. At any rate, sunspots are invisible to the naked eye. Of course, their effect can be seen as they light up Earth's northern skies with Aurora Borealis.
Satellite views »

Cycle Numbers. Scientists have been numbering the solar cycles since 1755. The current sunspot cycle is number 23. It is expected to end early in 2007. Here are the dates for the cycles:

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hamrodforu

Posts: 12 Member Since:02/23/10

#22 [url]

Feb 23 10 12:56 PM

The Latest Solar Maximum. Solar scientists calculated that the Sun reached the peak of its most-recent eleven-year sunspot activity cycle in April 2000. The so-called "solar maximum" is the two-to-three year period around the peak of activity when the Sun appears most tempestuous and Earth is buffeted with powerful solar gusts.

The Solar Cycle 23 peak seems to have been the month of April 2000 when the smoothed sunspot number (SSN) was 120.8.

What are smoothed sunspot numbers? When the daily sunspot count is plotted over a month's time, the graph is very spiky. Averaging daily sunspot numbers over a month results in the monthly average sunspot number, however it also results in a spiky plot. A smoother plot is desired by researchers. To get that, they choose a more averaged, or smoothed, measurement to measure solar cycles. This is the so-called smoothed sunspot number (SSN) calculated across five and a half months of data before and after a desired month, plus the data for the desired month. The amount of smoothing leaves the official SSN a half year behind the current month.

Cycle 23 like Cycle 20. Solar scienists suggest that Cycle 23 is much like Cycle 20 was in the way it rose and fell. Cycle 20 took about four years to reach peak and about seven uears to descend to minimum. If the two are alike, that could mean that Cycle 23 will reach bottom in 2007. The peak of Cycle 24 then could come in 2011.

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nittin4u

Posts: 11 Member Since:02/23/10

#23 [url]

Feb 23 10 12:57 PM

Magnetic flip. An additional indication that Cycle 23 peaked in the year 2000 came in a NASA report in February 2001 that the Sun's magnetic field had flipped. That means that Sun's north pole, which had been in the northern hemisphere of the Sun before the flip, now is in the southern hemisphere.The flip really wasn't a surprise since it seems to happen at the peak of each solar cycle. Negative Effects. Sunspots throw masses of coronal material out from the Sun. The particles take three days to reach Earth where the mass of plasma can send satellites tumbling and stress power systems. In the 20th century the solar maximum was known to have changed the computer programming inside orbiting satellites and shut down power grids on the surface of our planet.

  • The Challenger disaster of 1986 had set shuttle flights back three years. NASA had to loft the Hubble Space Telescope in a shuttle, but had trouble scheduling a launch. There was a shortage of fuel and competing demands for rides pushed the flight to a time when the Sun was blossoming with sunspots. An eleven-year peak in the sunspot cycle was approaching. Those exploding gases on our star heated Earth's upper atmosphere, expanded it deeper into space and caused extra drag on satellites. That threatened to pull the 12-ton, 43-ft. Hubble down to a lower orbit from which it might fall to Earth like a meteor. The sunspots gave NASA an exasperating choice -- launch Hubble so high a shuttle might not be able to reach it for repair, or launch it so low shuttles would have to fly every six months to boost it higher. The agency decided to delay launch to prevent frequent service flights. At last, Hubble was loaded aboard Discovery and on April 24, 1990, ferried to an orbit. 

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nittin4u

Posts: 11 Member Since:02/23/10

#24 [url]

Feb 23 10 12:57 PM

  • Solar storms during the period of peak sunspots in 1989-91 caused power failures in Canada and Sweden, made some computers crash in the United States, and destroyed or damaged several satellites.
  • During the sunspot peak in 1989, a blast of solar energy arriving at Earth shut down the electrical power grid in the Canadian province of Quebec, leaving six million customers in the dark for a day.
  • Global Positioning System (GPS) satellites tell users where they are within a few feet. If, for instance, solar energy caused them to provide less accurate data for a few hours, that could cause problems for airplanes landing.
After the 1989-91 problems, NASA, NOAA and other government agencies rushed to set up an early-warning system. Predictions are better today, but not yet perfect.
  • Power operators along the East Coast of North America were alerted to respond promptly to a solar burp in July 2000. They cut the output from their generators to avoid overloads. Even so, their transformers overheated and circuit breakers tripped.
Satellites Report Outbursts. As the Sun's most recent stormy season peaked in the year 2000, solar scientists used their coordinated fleet of satellites and ground observatories to watch out for angry outbursts of solar radiation and predict the impact of turbulent space weather. 

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hamrodforu

Posts: 12 Member Since:02/23/10

#25 [url]

Feb 23 10 12:58 PM

In a briefing today at NASA headquarters, solar physicists announced that the solar wind is losing power.  “The average pressure of the solar wind has dropped more than 20% since the mid-1990s,” says Dave McComas of the Southwest Research Institute in San Antonio, Texas. “This is the weakest it’s been since we began monitoring solar wind almost 50 years ago.”

McComas is principal investigator for the SWOOPS solar wind sensor onboard the Ulysses spacecraft, which measured the decrease. Ulysses, launched in 1990, circles the sun in a unique orbit that carries it over both the sun’s poles and equator, giving Ulysses a global view of solar wind activity.

… “What we’re seeing is a long term trend, a steady decrease in pressure that began sometime in the mid-1990s,” explains Arik Posner, NASA’s Ulysses Program Scientist in Washington DC.

How unusual is this event?  “It’s hard to say. We’ve only been monitoring solar wind since the early years of the Space Age-from the early 60s to the present,” says Posner. “Over that period of time, it’s unique. How the event stands out over centuries or millennia, however, is anybody’s guess. We don’t have data going back that far.”

… “The solar wind isn’t inflating the heliosphere as much as it used to,” says McComas. “That means less shielding against cosmic rays.”

In addition to weakened solar wind, “Ulysses also finds that the sun’s underlying magnetic field has weakened by more than 30% since the mid-1990s,” says Posner. “This reduces natural shielding even more.”

Unpublished Ulysses cosmic ray data show that, indeed, high energy (GeV) electrons, a minor but telltale component of cosmic rays around Earth, have jumped in number by about 20%.  These extra particles pose no threat to people on Earth’s surface. Our thick atmosphere and planetary magnetic field provide additional layers of protection that keep us safe.

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hamrodforu

Posts: 12 Member Since:02/23/10

#26 [url]

Feb 23 10 12:59 PM

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.

“Sunspot counts are at a 50-year low,” says solar physicist David Hathaway of the NASA Marshall Space Flight Center. “We’re experiencing a deep minimum of the solar cycle.”

… If solar activity continues as low as it has been, 2008 could rack up a whopping 290 spotless days by the end of December, making it a century-level year in terms of spotlessness.

Hathaway cautions that this development may sound more exciting than it actually is: “While the solar minimum of 2008 is shaping up to be the deepest of the Space Age, it is still unremarkable compared to the long and deep solar minima of the late 19th and early 20th centuries.” Those earlier minima routinely racked up 200 to 300 spotless days per year.

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nittin4u

Posts: 11 Member Since:02/23/10

#27 [url]

Feb 23 10 12:59 PM

The effect of solar activity on Earth’s climate is hotly debated, an insurgent theory vs. the dominant paradigm in climate science.  At the center of the cu rent debate are Henrik Svensmark and Nigel Calder, authors of The Chilling Stars: A New Theory of Climate Change.  They believe that cosmic rays have more effect on the climate than manmade CO2. 
An explanation of this theory by John-x in a comment posted at Watts Up with That?

It’s called ISCCP – International Satellite Cloud Climatology Project – a long-term record of satellite-based observations of cloud cover.  Svensmark used it to show good correlation between increased GCR (galactic cosmic radiation) and low cloud cover.   {see this page for more about cosmic rays}

GCRis more abundant during solar minimum (like now).  The theory is that very high-energy neutrons which were blasted out of exploding stars elsewhere in the galaxy hit the atmosphere, and produce a cascade of smaller energetic particles, some of which end up ionizing (producing an electric charge) in the lower atmosphere.  The electric charge increases the formation of aerosols, including sulphuric acid, which both provide nuclei on which water droplets can condense, and attract dust, sea salt, pollen, etc, to provide more and larger condensation nuclei.

The effect of ionization by GCR in this theory is to preferentially produce low clouds.  It is known that low clouds, by themselves, produce net cooling at the surface, whereas high clouds, by themselves, produce net warming.

So a process which preferentially produces low clouds would also preferentially produce cooler temperatures.

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nelson

Posts: 20 Member Since:04/14/10

#28 [url]

Apr 15 10 4:41 PM

The Solar Cycle 24 Prediction Panel has reached a consensus decision on the prediction of the next solar cycle (Cycle 24). First, the panel has agreed that solar minimum occurred in December, 2008. This still qualifies as a prediction since the smoothed sunspot number is only valid through September, 2008. The panel has decided that the next solar cycle will be below average in intensity, with a maximum sunspot number of 90. Given the predicted date of solar minimum and the predicted maximum intensity, solar maximum is now expected to occur in May, 2013. Note, this is a consensus opinion, not a unanimous decision. A supermajority of the panel did agree to this prediction.

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lady

Posts: 20 Member Since:04/14/10

#29 [url]

Apr 16 10 8:56 AM


Solar Cycle Progression


See link for graph. Wow, the sun is essentially "flatlining." They have to keep moving the "predicted" values, because they're not happening. And according to Space Weather see http://www.spaceweather.com ) a small new sunspot is forming but polarity indicates it is a "holdover" of SC 23, not a start for SC24. What this will mean for the continuation of the current solar minimum and its effects on climate is yet to be known. I'd be much more concerned with a continued cooling trend than warming at this point.


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wilson

Posts: 20 Member Since:04/18/10

#30 [url]

Apr 18 10 4:25 PM

The Solar Cycle 24 Prediction Panel has reached a consensus decision on the prediction of the next solar cycle (Cycle 24). First, the panel has agreed that solar minimum occurred in December, 2008. This still qualifies as a prediction since the smoothed sunspot number is only valid through September, 2008. The panel has decided that the next solar cycle will be below average in intensity, with a maximum sunspot number of 90. Given the predicted date of solar minimum and the predicted maximum intensity, solar maximum is now expected to occur in May, 2013. 

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sispy

Posts: 1,579 Member Since:11/05/08

#31 [url]

Apr 27 10 10:02 AM

 

Sun poised to erupt ?

SpaceWeather.com speculates that the Sun may be poised to erupt again.
They say that already this month, the sun has produced two of the biggest eruptions in years on April 13 and 19 when magnetic filaments became unstable and exploded.
A prominence on the eastern limb of the sun apparently resembles the precursors of those two earlier blasts, see picture at
http://www.spaceweather.com/images2010/26apr10/
eit304.gif?PHPSESSID=b9shrb1mtopof4momnd65bu8d6

SpaceWeather
http://www.spaceweather.com/

For the latest information about Ham Radio, Communications, Radio News, Space, Radio History...Join me in the discussion at hamchatforum.lefora.com

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sispy

Posts: 1,579 Member Since:11/05/08

#33 [url]

Apr 27 10 5:40 PM

http://www.google.com/#hl=en&source=hp&q=what+is+solar+cycle+progression&btnG=Google+Search&aq=f&aqi=&aql=&oq=what+is+solar+cycle+progression&gs_rfai=&fp=3f73b7d243bf661
It might be interesting to take a look at some links on google about the question of the sunspots and resulting solar cycle progression. The sunspot cycle roughly follows an eleven year cycle. We should be somewhere in cycle 24 now. It is not an exact science! The importance of the sunspot cycle progression is of great interest to those who use the radio shortwave bands. There is quite a bit of information about sunspots here and in other ham radio publications. It might be useful to enter the phrase in the GOOGLE CUSTOM SEARCH (top of each page in this forum) for further information in this forum.

For the latest information about Ham Radio, Communications, Radio News, Space, Radio History...Join me in the discussion at hamchatforum.lefora.com

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enigma685

Posts: 1,325 Member Since:12/07/08

#34 [url]

May 11 10 1:43 AM

Weekend solar flares

This weekend, magnetic fields around sunspot 1069 became unstable and erupted - over and over again.
On May 8th alone, the active region produced more than half a dozen flares. High-resolution movies from NASA's Solar Dynamics Observatory show that even the "minor" eruptions were jaw-dropping spectacles.
Visit http://spaceweather.com for highlights.

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vasl

Posts: 50 Member Since:04/22/10

#35 [url]

May 11 10 10:11 AM

Solar Cycle Progression 
The charts on this page depict the progression of the Solar Cycle. The charts and tables are updated by the Space Weather Prediction Center monthly using the latest ISES predictions. Observed values are initially the preliminary values which are replaced with the final values as they become available.

Solar Cycle 24 Prediction Update released May 8, 2009

May 8, 2009 -- The Solar Cycle 24 Prediction Panel has reached a consensus decision on the prediction of the next solar cycle (Cycle 24). First, the panel has agreed that solar minimum occurred in December, 2008. This still qualifies as a prediction since the smoothed sunspot number is only valid through September, 2008. The panel has decided that the next solar cycle will be below average in intensity, with a maximum sunspot number of 90. Given the predicted date of solar minimum and the predicted maximum intensity, solar maximum is now expected to occur in May, 2013. Note, this is a consensus opinion, not a unanimous decision. A supermajority of the panel did agree to this prediction.

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sispy

Posts: 1,579 Member Since:11/05/08

#37 [url]

Feb 16 11 6:44 PM

First X-flare of the new solar cycle

Earth-orbiting satellites have detected the strongest solar flare in more than four years.
At 0156 UT on February 15th, giant sunspot 1158 unleashed an X2-class eruption. X-flares are the strongest type of
x-ray flare, and this is the first such eruption of new Solar Cycle 24.
The explosion that produced the flare also sent a solar tsunami rippling through the sun's atmosphere and, more importantly, hurled a coronal mass ejection toward Earth. This raises the possibility of geomagnetic storms in the days ahead.
Visit http://spaceweather.com for images and updates.

For the latest information about Ham Radio, Communications, Radio News, Space, Radio History...Join me in the discussion at hamchatforum.lefora.com

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enigma685

Posts: 1,325 Member Since:12/07/08

#38 [url]

May 12 11 10:35 AM

Solar Flux Index drops below 100 again

On Tuesday May 10, 2011 the daily solar flux index (SFI) fell below 100 (97.5) for the first time since March 22, 2011.
During this month the daily sunspot count has been as high as 90 but the sunspot groups have for the most part been small, weak and magnetically simple.
Radiowave propagation continues good on 15 and 12 meters but has become a bit more sporadic on 10 meters. 6 meters is seeing more and more sporadic E (Es) openings as we enter the traditional northern hemisphere warm season pattern.
For now the sun has returned to it's quiet state as we experienced in early 2011 on back. Even as solar cycle 24 continues it's rise to a smoothed sunspot number (SSN) maximum of ~95 in December 2013, we will continue to see periods of abnormal sunspot production with groups small, weak and magnetically simple.
Several years ago all government, university and private entities were forecasting a very large solar cycle 24. As a now retired Solar & Space Plasma Physicist as well as a Meteorologist/Climatologist, I was the only one forecasting a weak one. Unfortunately so far my forecast has been correct as I still believe the sun is headed for a Maunder type minimum in solar output and a continued cooling of earth's climate.
73 & GUD DX,
Thomas F. Giella, NZ4O
Lakeland, FL, USA
solarcycle24@tampabay.rr.com
NZ4O Solar Space Weather & Geomagnetic Data Archive: http://www.solarcycle24data.org
NZ4O HF/6M Radiowave Propagation Forecast: http://www.solarcycle24.org

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sispy

Posts: 1,579 Member Since:11/05/08

#39 [url]

Jul 28 11 2:16 PM

Big Sunspot Notice

After more than a week of quiet, solar activity is picking up with the emergence of two large sunspot groups on the sun's northeastern limb.
The active regions are crackling with C- and M-class solar flares. So far none of the eruptions has been squarely Earth directed, but that could change in the days ahead as solar rotation turns the sunspots to face our planet.
Visit http://spaceweather.com for images and more information.

For the latest information about Ham Radio, Communications, Radio News, Space, Radio History...Join me in the discussion at hamchatforum.lefora.com

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enigma685

Posts: 1,325 Member Since:12/07/08

#40 [url]

Aug 20 11 8:07 PM

Sunspot peaks could be lower

The BBC reports on research which indicates that within decades, solar storms are likely to become more disruptive to planes and spacecraft but sunspot peaks will be lower.
The work, published in Geophysical Research Letters, predicts that once the Sun shifts towards an era of lower solar activity, more hazardous radiation will reach Earth. The team says the Sun is currently at a grand solar maximum. This phase began in the 1920s - and has lasted throughout the space age.
Mike Lockwood, professor of space environment physics at Reading, said: "All the evidence suggests that the Sun will shortly exit from a grand solar maximum that has persisted since before the start of the space age.
In a grand solar maximum, the peaks of the 11-year sunspot cycle are larger and the average number of solar flares and associated events such as coronal mass ejections are greater.
On the other hand in a grand solar minimum there are almost no sunspots for several decades. The last time this happened was during the Maunder Minimum, between about 1650 and 1700."
The research indicates that most radiation hits the Earth during periods of middling solar activity. Increased radiation is a particular problem for aviation and communications - technology that did not exist the last time the sun cycle ended its grand maximum.
Read the full BBC story at
http://www.bbc.co.uk/news/science-environment-14580995
Mike Lockwood - Solar Induced Climate Effects
http://www.eiscat.rl.ac.uk/Members/mike/publications/
pdfs/Sun_Climate_final.pdf

Other papers by Mike Lockwood
http://www.eiscat.rl.ac.uk/Members/mike/publications/

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