Editor's Notes

New Items on the AAVSO Website

• SID Antenna
  At the request of several parties, Mike Hill (A87) has produced a document containing suggestions and guidance on antenna design and construction. Included are contributions by Art Stokes (A62), Cap Hossfield (A09), Guglielmo DiFillipo (A93), and Mike himself. The material should prove quite useful to prospective observers who are interested in building and using various Gyrator-type receivers.
• Spreadsheet for Calculating Sunspot Number Statistics
  William Wilson (WILW) has contributed an Excel spreadsheet that, given a set of observer's daily R-numbers, computes a variety of statistics with respect to the AAVSO's Ra number and the International number, Ri. Although the calculations differ from those employed by the AAVSO, the spreadsheet offers a useful means of tracking performance.

A beta version of the software should be available by the middle of next month, and we will be in need of a small group of volunteers to put it through its paces. Please email me at my hotmail address on the front of the Bulletin if you would like to participate in a test of the program before it is put on the website for general use. Be aware that, as a participant, you will need to send two reports at the end of the month: your "normal" report, using whatever format you customarily use, and a report that uses the new format. I expect that the need to file dual reports will occur only once.

Solar Filter Review
The April issue of Astronomy magazine (Kalmbach Publishing Co.) contains a review and evaluation of solar filters that may be of interest to observers.

Change in Sun's Polarity
Several sources (e.g., NASA's website, Science News, v.159, 1) have reported on the changing polarity of the sun, a major event associated with the arrival of solar maximum. As of this writing, the magnetic pole in the northern hemisphere now points south, and the southern pole is expected to complete the reversal shortly by pointing north. Time to flip your Stonyhursts!

Detection of Gamma Ray Burst by SID Observers
As observers who are interested in Gamma Ray Burst (GRB) detection and subscribe to the GRB Alert network are already aware, the occurrence of GRB010222 was apparently detected as an SES event during the month by the A52 team of Danie Overbeek and Domenic Toldo in South Africa. The detection was made with the aid of VLF receivers and demonstrates the potential of SID equipment to contribute to this exciting area of study. The SID Supplement this month contains details on the discovery.

SID and visual observers who want to keep abreast of developments in this area are urged to join the GRB Discussion Group and sign up to receive Alert Notices that are issued when suspected GRB events are detected.

New Observers in February
Sunspot reports were received from three new observers during the month: Jim Bedient (BEDJ), Hawaii; Rana Khan (KHAR), India; and Mieczyslaw Szulc (SZUM), Poland. SID reports were received from two new observers: Ted Poulos (A95), Massachusetts; and Roberto Battaiola (A96), Italy. Readers of the Bulletin will recognize that Roberto is also a long-time contributor of sunspot data.

Thank you all very much for your contributions and welcome to the AAVSO's Solar Division.

Clear skies,

-CEF

• Back to February Solar Bulletin
• Sudden Ionospheric Disturbance Report
• Sudden Ionospheric Disturbances Supplement