Daily Archives: April 20, 2014

The Sun Online and solar activity. April 20, 2014

Twelve active regions were reported by NOAA today. Three of them (NOAA ARs 2034, 2035, and 2036) have beta-gamma configuration of the photospheric magnetic field. These three active regions and four others were responsible for numerous C-class flares yesterday and today. None of them was associated with an Earth-directed CME. The strongest flare of the past 24 hours was the C6.4 flare peaking at  08:13 UT today in the NOAA AR 2032 at the west solar limb. We expect further flaring activity on the C-level,
with a good chance for an M-class event. An interplanetary shock-like structure was detected this morning. ACE recorded jumps of solar wind speed, temperature, and the interplanetary magnetic filed (IMF) magnitude at 10:23 UT. SOHO/CELIAS detected a jump in density at 10:22 UT, but the jump in speed was detected only 20 to 30 minutes later. Therefore, this discontinuity does not seem to be a typical ICME-driven fast forward shock as ACE did not detect a jump in density at all, and jumps in density and
the solar wind speed detected by SOHO/CELIAS were not simultaneous. There is, however, very little doubt that this is a start of an ICME corresponding to the halo CME observed on the Sun on April 18. During the intervals of the strongest IMF magnitude in the post-shock solar wind flow (up to 22 nT), the north-south IMF component Bz was either northward or close to zero. Unsettled geomagnetic conditions (K = 3) were reported by Dourbes and NOAA, and active conditions (K = 4) were reported by IZMIRAN.
Currently the IMF magnitude is around 12 nT and the solar wind speed is around 650 km/s, so minor geomagnetic storm conditions (K = 5) are still possible. After the arrival of the shock-like structure, the proton flux at energies above 10 MeV decreased to values below the threshold of the proton event. The proton flux, however, remains high, and in case of another solar eruption with associated SEPs, the event threshold could be easily crossed. We therefore issue a warning condition for a proton event.

Equipment: Coronado 90 +  Imaging Source DMK  + LX75
Processing: Photoshop, Avistack 300 frames
Date: 04/20/14
Time UT: 19:00
Exposure 1/182 sec.

With SPONLI Space is getting closer


Ash and Lightning above an Icelandic Volcano 

Image Credit & Copyright: Sigurður Stefnisson

Why did a picturesque 2010 volcanic eruption in Iceland create so much ash? Although the large ash plume was not unparalleled in its abundance, its location was particularly noticeable because it drifted across such well-populated areas. The Eyjafjallajökull volcano in southern Iceland began erupting on 2010 March 20, with a second eruption starting under the center of a small glacier on 2010 April 14. Neither eruption was unusually powerful. The second eruption, however, melted a large amount of glacial ice which then cooled and fragmented lava into gritty glass particles that were carried up with the rising volcanic plume. Pictured above during the second eruption, lightning bolts illuminate ash pouring out of the Eyjafjallajökull volcano.

NASA APOD 20-Apr-14

NGC 1999: Reflection Nebula in Orion

ec9ab6d64a217232ca1353edb2ec6d58.1824x0_q100_watermark NGC 1999 is a dust filled bright nebula with a vast hole of empty space represented by a black patch of sky, as can be seen in the photograph. It is a reflection nebula, and shines from the light of the variable star V380 OrionisNGC 1999 lies about 1500 light-years away in the constellation Orion, just south of Orion’s well known emission nebula, M42.

Imaging telescopes or lenses: Intes Micro MN84
Imaging cameras: QSI 583 wsg
Mounts: Astro-Physics 1200 GTO
Guiding cameras: Starlight Xpress Lodestar
Software: Adobe Photoshop CC, PixInsight
Filters: Astrodon Luminance, Astrodon RGB filter set
Dates: Dec. 28, 2013
Astrodon Luminance: 12×900″
Astrodon RGB filter set: 90×900″
Integration: 25.5 hours

Author: Dean Salman

AstroPhotography of the day by SPONLI
20 April 2014