Although our Sun has been quite for the last years, recently I had the occasion to observe flares occurring on the solar disk. Unfortunately, my observations are limited to Saturday and Sunday due to working duties.
On Sunday, March 4th, the page http://www.spaceweather.com reported that class M flares could occur at the big sunspot (NOAA 1429) which was emerging from the solar limb. As a matter of fact, around 11 UT, I got a evident emission of light from the cited sunspot. In the following, the photographic documentation of the phenomenon is reported. Due to the presence of clouds, no pictures were taken before and immediately after. In the afternoon, when the sky was clear again the phenomenon had ceased.
Films were recorded at 11 (figures 1,2) and at 14 UT (figures 3,4) at the direct focus (full disk) and through a 2X Barlow lens (details of the chromosphere). An approximate dimension of the 1429 sunspot (from an image of the sunspot got through a Baader Planetarium Calcium K-Line Filter + AstroSolar™, visual density 3.8) is about 90,000.x 60,000 km.
On March 5th and 7th, at 04:13 and 00:28 UT, the NASA’s Solar Dynamics Observatory got eruptions of X1 and X5 class (much more energetic than that I observed), respectively, occurring at NOAA 1429 (http://www.spaceweather.com).
Place, instrumentation and data collection.
Pontedera, Pisa. Televue 101 f/5,4 telescope on a HEQ5 mounting. DMK 51AU02 USB monochromatic camera. SolarMax 60 (+ BF15 blocking filter) H filter (Coronado Instruments). Collection of 600-800 (chromosphere) or 300-400 (prominences) frames at 12 f/s. Treatment of data: Registax 5.0 and Photoshop programs.
Images by Guido Pampaloni, astronomical centre association.