NASA Solar Cycle News


Info from:



2010 Oct 5

Solar Cycle Prediction  

The solar cycle 24 predicted sunspot maximum has been reduced again – predicted peak down to the 60-70 range, expected in July 2013. See the entries below for:

·         2009 May 29: predicted peak: 80-90 range

·         2009 Jan 5: predicted peak: 100-110 range

·         2008 Mar 28: predicted peak: 130-140 range



A number of techniques are used to predict the amplitude of a cycle during the time near and before sunspot minimum. Relationships have been found between the size of the next cycle maximum and the length of the previous cycle, the level of activity at sunspot minimum, and the size of the previous cycle. Among the most reliable techniques are those that use the measurements of changes in the Earth's magnetic field at, and before, sunspot minimum. These changes in the Earth's magnetic field are known to be caused by solar storms but the precise connections between them and future solar activity levels is still uncertain.





2010 Mar 12

Solar ‘Current of Fire’ Speeds Up


the top of the sun's Great Conveyor Belt has been running at record-high speeds for the past five years. I believe this could explain the unusually deep solar minimum we've been experiencing," says Hathaway. "The high speed of the conveyor belt challenges existing models of the solar cycle and it has forced us back to the drawing board for new ideas."

First, it coincided with the deepest solar minimum in nearly 100 years, contradicting models that say a fast-moving belt should boost sunspot production. So where have all the sunspots been? The solar minimum of 2008-2009 was unusually deep and now the sun appears to be on the verge of a weak solar cycle. Instead of boosting sunspots, Hathaway believes that a fast-moving Conveyor Belt can instead suppress them




[A note: Compare this entry (2010/03/12 – “sun's Great Conveyor Belt has been running at record-high speeds for the past five years”) with the entry for 2006/05/10 – “Sun's Great Conveyor Belt has slowed to a record-low crawl, according to research by NASA solar physicist David Hathaway "It's off the bottom of the charts,”]





2009 May 29

New Solar Cycle Prediction


An international panel of experts led by NOAA and sponsored by NASA has released a new prediction for the next solar cycle. Solar Cycle 24 will peak, they say, in May 2013 with a below-average number of sunspots. “If our prediction is correct, Solar Cycle 24 will have a peak sunspot number of 90, the lowest of any cycle since 1928 when Solar Cycle 16 peaked at 78," says panel chairman Doug Biesecker of the NOAA Space Weather Prediction Center.






2009 Apr 1

Deep Solar Minimum


There were no sunspots observed on 266 of the [2008] year's 366 days (73%). To find a year with more blank suns, you have to go all the way back to 1913, which had 311 spotless days. Sunspot counts for 2009 have dropped even lower. As of March 31st, there were no sunspots on 78 of the year's 90 days (87%). "This is the quietest sun we've seen in almost a century"


In 2008, the sun set the following record: A 50-year low in solar wind pressure: Measurements by the Ulysses spacecraft reveal a 20% drop in solar wind pressure since the mid-1990s—the lowest point since such measurements began in the 1960s. The solar wind helps keep galactic cosmic rays out of the inner solar system. With the solar wind flagging, more cosmic rays are permitted to enter.




Predictions of solar cycle 24 amplitude vary widely from 40 to 185. The following plot shows the wide range of predictions (click for larger plot).





2009 Jan 5

Solar Cycle Prediction  

The solar cycle 24 predicted sunspot maximum has been reduced (see the entry below for 2008 Mar 28)




2008 Dec 16

A Giant Breach in Earth’s Magnetic Field   

“NASA's five THEMIS spacecraft have discovered a breach in Earth's magnetic field ten times larger than anything previously thought to exist. Solar wind can flow in through the opening to "load up" the magnetosphere for powerful geomagnetic storms. High above Earth's poles, solar and terrestrial magnetic fields linked up (reconnected) to form conduits for solar wind. Conduits over the Arctic and Antarctic quickly expanded. The great breach of June 2007, however, opened in response to a solar magnetic field that pointed north. "This completely overturns our understanding of things." "We're entering Solar Cycle 24. For reasons not fully understood, CMEs in even-numbered solar cycles (like 24) tend to hit Earth with a leading edge that is magnetized north. Such a CME should open a breach and load the magnetosphere with plasma just before the storm gets underway. It's the perfect sequence for a really big event."





2008 Oct 30

Magnetic Portals Connect Sun and Earth

“During the time it takes you to read this article, something will happen high overhead that until recently many scientists didn't believe in. A magnetic portal will open, linking Earth to the sun 93 million miles away. Tons of high-energy particles may flow through the opening before it closes again. It's called a flux transfer event or FTE. On the dayside of Earth (the side closest to the sun), Earth's magnetic field presses against the sun's magnetic field. Approximately every eight minutes, the two fields briefly merge or "reconnect," forming a portal through which particles can flow. “




2008 Sep 23

Solar Wind Loses Power, Hits 50-year Low

“The average pressure of the solar wind has dropped more than 20% since the mid-1990s … the speed of the million mph solar wind hasn't decreased much—only 3%. The change in pressure comes mainly from reductions in temperature and density. The solar wind is 13% cooler and 20% less dense. The solar wind isn't inflating the heliosphere as much as it used to … That means less shielding against cosmic rays. Ulysses also finds that the sun's underlying magnetic field has weakened by more than 30% since the mid-1990s “





2008 Mar 28

Old Solar Cycle Returns

Barely three months after forecasters announced the beginning of new Solar Cycle 24, old Solar Cycle 23 has returned."This week, three big sunspots appeared and they are all old cycle spots," says NASA solar physicist David Hathaway. "We know this because of their magnetic polarity." All are oriented according to the patterns of Solar Cycle 23. Cycle 24 spots would be reversed. "We have two solar cycles in progress at the same time. Solar Cycle 24 has begun (the first new-cycle spot appeared in January 2008), but Solar Cycle 23 has not ended." Based on this latest spate of "old" activity, he thinks the next Solar Max probably won't arrive until 2012.




2008 Jan 10

Solar Cycle 24 Begins

On January 4, 2008, a reversed-polarity sunspot appeared—and this signals the start of Solar Cycle 24. Sunspot 981 was small--only about as wide as Earth, which counts as small on the grand scale of the sun--and it has already faded away. But its three day appearance on Jan. 4-6 was enough to convince most solar physicists that Solar Cycle 24 is underway.




2007 Dec 14

Is a New Solar Cycle Beginning?

“A patch of magnetism could be a sign of the next solar cycle. For more than a year, the sun has been experiencing a lull in activity. Many forecasters believe Solar Cycle 24 will be big and intense. Peaking in 2011 or 2012.




2006 Dec 21

Scientists Predict Big Solar Cycle

Solar cycle 24, due to peak in 2010 or 2011 "looks like its going to be one of the most intense cycles since record-keeping began almost 400 years ago". Hathaway and Wilson looked at records of geomagnetic activity stretching back almost 150 years and noticed something useful:. "The amount of geomagnetic activity now tells us what the solar cycle is going to be like 6 to 8 years in the future," says Hathaway. According to their analysis, the next Solar Maximum should peak around 2010 with a sunspot number of 160 plus or minus 25. This would make it one of the strongest solar cycles of the past fifty years.

In the plot above left, black curves are solar cycles; the amplitude is the sunspot number. Red curves are geomagnetic indices, specifically the Inter-hour Variability Index or IHV. The plot above right shows the prediction for solar cycle 24.




2006 May 10

Long Range Solar Forecast

The Sun's Great Conveyor Belt has slowed to a record-low crawl, according to research by NASA solar physicist David Hathaway. "It's off the bottom of the charts," he says. "This has important repercussions for future solar activity." The Great Conveyor Belt is a massive circulating current of fire (hot plasma) within the Sun. It has two branches, north and south, each taking about 40 years to perform one complete circuit. Researchers believe the turning of the belt controls the sunspot cycle, and that's why the slowdown is important. According to theory and observation, the speed of the belt foretells the intensity of sunspot activity ~20 years in the future. "The slowdown we see now means that Solar Cycle 25, peaking around the year 2022, could be one of the weakest in centuries," says Hathaway.

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In red, David Hathaway's predictions for the next two solar cycles and, in pink, Mausumi Dikpati's prediction for cycle 24.




2006 Mar 10

Solar Storm Warning

It's official: Solar minimum has arrived. Sunspots have all but vanished. Solar flares are nonexistent. The sun is utterly quiet. This week researchers announced that a storm is coming--the most intense solar maximum in fifty years. The prediction comes from a team led by Mausumi Dikpati of the National Center for Atmospheric Research (NCAR). "The next sunspot cycle will be 30% to 50% stronger than the previous one," Dikpati's forecast puts Solar Max at 2012. Hathaway believes it will arrive sooner, in 2010 or 2011. "I expect to see the first sunspots of the next cycle appear in late 2006 or 2007—and Solar Max to be underway by 2010 or 2011."




2005 Sep 15

Solar Minimum Explodes

Sept. 7th, a huge sunspot rounded the sun's eastern limb. As soon as it appeared, it exploded, producing one of the brightest x-ray solar flares of the Space Age. The solar minimum, the lowest point of the sun's 11-year activity cycle, isn't due until 2006, but forecasters expected 2005, the eve of solar minimum, to be a quiet year on the sun. The sunspots of 2005, while fewer, have done more than their share of exploding. Sunspot 798/808, the source of the Sept 7th superflare and eight lesser X-flares. All by itself, this sunspot has made Sept. 2005 the most active month on the sun since March 1991. Much about the sun's activity cycle remains unknown. This means we don't know what is typical. Scientists have monitored only three complete solar cycles using satellite technology.

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