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LOTS OF SUNSPOTS, NOT MUCH ACTIVITY: The solar disk is peppered with sunspot groups, at least eight of them. None of them, however, are producing strong flares. Solar activity remains generally low.
GIANT SINE WAVE: Imagine a sine wave 400,000 km long. Today, NASA's Solar Dynamics Observatory is monitoring just such a structure. It's an enormous filament of magnetism slithering over the sun's northeastern limb:
One of the wave troughs appears to be passing through the core of sunspot 1283. If so, an eruption of the sunspot could have an interesting ripple effect on the greater filament, perhaps even causing it to collapse. Readers with solar telescopes are encouraged to monitor this region so full of possibilities. (Note: An earlier version of this news item mislabeled the sunspot--it said "1282" when in fact "1283" is the correct active region.)
A COMET AMONG THE STARS: As September begins, green Comet Garradd is gliding across the star fields of the Milky Way in the early evening sky. The icy visitor from tthe outer solar system is not yet visible to the naked eye, but it looks great through amateur telescopes (recommended: The Comet Hunter). Maximilian Teodorescu sends this picture from his backyard observatory in Comana, Romania:
"I took the picture using my 8-inch telescope--a 34 minute exposure at ISO 6400," says Teodorescu. "The comet looks so nice in front of the Milky Way."
Astrophotographer Pete Lawrence of Selsey UK points out that Comet Garradd is approaching Brocchi's Cluster--also known as "the Coathanger." Lawrence photographed the approach on August 31st. "The best night for a photo opportunity between Garradd and The Coathanger is on the 2nd of September leading into the morning of the 3rd, when the comet will pass very close to the hook of the hanger."
At the moment, Comet Garradd is a purely telescopic object. It is, however, approaching the sun and brightening. Recent projections place it at peak magnitude 6, on the threshold of naked-eye visibility, in February 2012. Because Comet Garradd is a first-time visitor to the inner solar system, it could behave in unexpected ways, perhaps exceeding those expectations. Stay tuned--and meanwhile browse the image links below.
more images: from Parks Squyres of SaddleBrooke, Arizona; from Chris Schur of Payson, Arizona; from Tamas Abraham of Zsambek, Hungary
comet links: finder charts, 3D orbit.
August 2011 Aurora Gallery
[previous Augusts: 2010, 2009, 2008, 2007, 2006, 2005, 2004, 2003, 2002]