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solar observing

AAVSO Sudden Ionospheric Disturbance Program Observers

Active Observers (Data submitted within the last year)

OBS ID Observer Name Station Location
A-94 Al McWilliams St Cloud, MN
A-96 Roberto Battaiola Milan, Italy
A-97 Jon Wallace Torrington, CT
A-118 Lionel Loudet Muret, France
A-120 Bob Terrill Ballarat, Victoria, Australia
A-121

The Zurich Classification System of Sunspot Groups

The Zurich Classification System of Sunspot Groups

Contributed by Tom Fleming (FLET)

 

"A" Type: One or more tiny spots that do not demonstrate bi-polarity or exhibit penumbra.

sunspota.jpg
 

"B" Type: Two or more tiny spots that demonstrate bi-polarity but do not exhibit penumbra.

sunspotb.jpg

 

 

 

 

Dances with Wolfs: A Short History of Sunspot Indices

Contributed by Carl E. Feehrer (FEEC)

Revised August 2000

Accuracy and Consistency in the Production of the American Sunspot Number (Ra)

Addendum

ACCURACY AND CONSISTENCY IN THE PRODUCTION OF THE AMERICAN SUNSPOT NUMBER (Ra)

Contributed by Carl E. Feehrer (FEEC)

Solar News

February 20, 2013

  • The NASA SDO mission released a fascinating video showing "rain" from a magnetic loop falling back onto the surface of the Sun.  It's not rain, but hot plasma magnetically levitated off the Sun!

February 15, 2013

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