There were five C flares on the Sun during the past 24 hours, the large majority being released by NOAA AR 11928. The brightest one was a C8.4 flare from NOAA AR 11936 peaking at 17:28 UT on December 23. In the next 48 hours, the probability for C flares is high (around 80%) and for M flares around 40%, mainly from NOAA AR 11928 and 11936. There is a slight chance for an X flare.In the past 24 hours, solar wind speed decreased from around 310 km/s to around 280 km/s and the magnitude of the Interplanetary Magnetic Field varied between 1.5 and 4 nT, as observed by ACE. Current geomagnetic conditions are quiet (K Dourbes between 0 and 2; NOAA Kp between 0 and 1) and are expected to remain so on December 24 and in the first half of December 25. In the second half of December 25, geomagnetic conditions may become active (K Dourbes = 4) due to the arrival of a coronal hole high speed stream with estimated velocity between 450 and 500 km/s. Quiet to active geomagnetic conditions (K Dourbes < 5) are expected on December 26, as the coronal hole high speed stream effects continue.
Equipment: Coronado 90 + SBIG 8300s + LX75
Time UT: 01:00
Exposure 0.8 sec.
With SPONLI Space is getting closer!
Image Credit & Copyright: Jeff Husted
Blown by fast winds from a hot, massive star, this cosmic bubble is huge. Cataloged as Sharpless 2-308 it lies some 5,200 light-years away toward the constellation of the Big Dog (Canis Major) and covers slightly more of the sky than a Full Moon. That corresponds to a diameter of 60 light-years at its estimated distance. The massive star that created the bubble, a Wolf-Rayet star, is the bright one near the center of the nebula. Wolf-Rayet stars have over 20 times the mass of the Sun and are thought to be in a brief, pre-supernova phase of massive star evolution. Fast winds from this Wolf-Rayet star create the bubble-shaped nebula as they sweep up slower moving material from an earlier phase of evolution. The windblown nebula has an age of about 70,000 years. Relatively faint emission captured in the expansive image is dominated by the glow of ionized oxygen atoms mapped to violet hues.
NASA APOD 24-dec-13
Mount: Takahashi-EM200 Temma2jr
Optics: Takahashi TSA-102s
Camera: ATIK-11000M classe2
filter wheel: Atik-EFW2
filter Astrodon H.Alpha-5nm LRGB
Guiding: Atik-314L+ -5° Via Astrodon Monster-MOAG
H.alpha: 15x1800sec ( 7h30 )
LRGB: 188.8.131.52x1800sec ( 5h )
Temp CCD: -20°c
Location: Gerarmer.88 ( Vosges France )
Autor: Jerome Greblac
24 December 2013
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