Here are today’s solar images taken from Al Sadeem Observatory, April 21, 2021.
The sky was mostly clear with intermittent light to moderate breeze which provided good transparency but average seeing at the time these images were taken.
Multiple minor B-class and C-class intensity solar flares were recorded from AR2816 (Cai/beta) and AR2817 (Dao/beta) as both exhibited some consolidation and gradual growth of their respective sunspot structures over the past 24 hours. On the other hand, AR2818 (Hsx/alpha) at the SE quadrant remains stable and inactive. Furthermore, a C1.9-class solar flare that originated from AR2814 (not visible) behind the southwestern limb was recorded by space weather agencies. The latest sunspot number (based on visual count and Wolf number calculation) is 45.
Other noteworthy solar features observed were the enhanced plages associated with the upper mentioned sunspot groups, few short filaments at the extreme northern section, and elongated huge eruptive ones at the southeastern-most sections of the Sun’s disk, and a few small faint quiescent and moderately huge eruptive prominences mainly at the NW and SE limbs, as distinctively captured in H-alpha imagery.
Space weather agencies* forecast solar activity to be at low to moderate levels with chances of solar flares of B-class to C-class (possibly up to M-class) intensity, mainly from the upper-mentioned active sunspot regions. Close monitoring is being conducted by numerous space weather agencies for any significant development.
Equipment used are Skywatcher 120mm refractor telescope with Baader filter and unmodified Canon EOS 1D Mark IV DSLR camera for visible imagery. For H-alpha imagery, the equipment used are Lunt 60mm H-alpha solar telescope, and QHYCCD 290III mono camera; all mounted on Skywatcher EQ6 pro mount Pre-processing of visible solar images was performed in PIPP, stacking in Autostakkert, slight wavelet adjustments in Registax 6, and post-processing in Adobe Photoshop CC.
*TECHNICAL REPORTS COURTESY OF SOLAR INFLUENCE DATA CENTER (SIDC), NOAA-SPACE WEATHER PREDICTION CENTER (NOAA-SWPC)
Weather Data (5:00 PM – 5:30 PM, April 21, 2021, from NCM Al Wathba Station):
Average Temperature: 38.2°C
Average Humidity: 9.0%
Average Wind Speed and Direction: 24.83 kph from NNW
Average Cloud Cover: 0%
Average Air Pressure: 999.07 hPa
Average Solar Radiation: 227.67 W/m^2