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What are sunspots?

The term "sunspot" appears in the news, often in connection with stories on aurorae, electrical outages, and problems with orbiting satellites.  But often these stories don't really explain what sunspots are and why they're of interest to us on Earth.  So what are sunspots?

The Gyrator III VLF Receiver

The latest version of the Gyrator series of VLF receivers (first developed in the 1990s) is the Gyrator III, a revision of Arthur Stokes' Gyrator II by Guglielmo Di Filippo (observer A-93).


Circuit diagrams and wiring for the Gyrator III are available here in Microsoft Word and PDF formats: .doc, .pdf

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

VLF Station List

VERY LOW FREQUENCY (VLF) RADIO STATIONS
                                     
           Station            Station     Frequency        Radiated
             Site               ID          (kHz)            Power
                                                             (kW)
  U.S. Navy                     
       Cutler, ME                NAA          24.0            1000
       Jim Creek, WA             NLK          24.8             250
       Lualualei, HI             NPM          21.4             566
       LaMoure, ND               NML          25.2             500

Solar Program, Reducing Data and Email Format

Solar Program, Reducing Data and Email Format

Reducing Data Gathered by VLF Monitoring Systems

(Extracted from SID Technical Bulletin Vol. 3, Number 4, Oct. 1992)

SID Monitoring Overview

SID Monitoring Overview
AAVSO SID Program

Rodney Howe, Solar Section chair & SID leader

So, what are we looking for? Here are a couple references of SID events and their influence on the ionosphere:

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)

Guidelines for new solar observers

Guidelines for New Solar Observers

  • Do not look directly at the sun without the protection offered by a filter. For naked eye viewing, a piece of #14 welder's glass provides adequate protection. Do not use overexposed film, dark glasses, or other media that are not designed specifically for solar viewing.

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