CFHT CLOUD CAM - TIME LAPSE SUNSET TO SUNRISE
DECEMBER 15, 2011
OUR SKYVIEW - BEST ENJOYED WITH FULL SCREEN!! :)
DECEMBER 15, 2011 spaceweather.com
BIG COMET PLUNGES TOWARD THE SUN: Comet Lovejoy (C/2011 W3) is diving into the sun and furiously vaporizing as it approaches the stellar surface. The Solar and Heliospheric Observatory (SOHO) is recording the kamikaze plunge.
"This is, without any doubt, the brightest sungrazing comet that SOHO has ever seen," says comet researcher Karl Battams of the Naval Research Lab in Washington DC.
The comet's nucleus, thought to be twice as wide as a football field, will skim approximately 140,000 km (1.2 solar radii) above the solar surface on Dec. 15/16. At such close range, solar heating will almost certainly destroy the comet's icy core, creating a cloud of vapor and comet dust that will reflect lots of sunlight.
"If Comet Lovejoy gets as bright as magnitude -4 or -5, there is a tiny but non-zero chance that it could become visible in the sky next to the sun," says Battams.
Indeed, something similar happened to Comet McNaught in January 2007 when it was visible in broad daylight: gallery. Standing in the shadow of a tall building to block the sun allowed the comet to be seen in blue sky nearby.
"Comet Lovejoy will be reaching perihelion (closest approach to the sun) right around sunset on Dec. 15th for people in the US East, Central, Mountain, and Pacific time zones," continues Battams. "Be alert for the comet to the left of the sun at that time." Caution: Do not look at or near the sun through unfiltered optics; focused sunlight can seriously damage your eyes.
Discovered on Dec. 2nd by amateur astronomer Terry Lovejoy of Australia, the comet is an unusually large member of the Kreutz family. Kreutz sungrazers are fragments of a single giant comet (probably the Great Comet of 1106) that broke apart back in the 12th century. SOHO sees one plunging into the sun every few days, but most are small, no more than 10 meters wide. Comet Lovejoy is at least ten times larger than usual.
UPDATE: COMET LOVEJOY HAS A COMPANION: "Comet Lovejoy has a friend!" reports Karl Battams in his blog. "Look for it in the upper-half near the sun moving perfectly in step with Lovejoy. It's another Kreutz-group comet. This is not surprising. SOHO's Kreutz-group comets are very 'clumpy,' for want of a better word. We frequently see them arrive in pairs or sometimes trios, and the big bright ones in particular will often have a little companion comet."
Venus, the brightest object in the night sky after the Moon, climbs into better view as the "evening star" this month, low in the west at sunset. The next-brightest object, Jupiter, is well up in the southeast at that hour, and climbs high across the sky after Venus drops from view. Beautiful Orion, the hunter, is in view all night, with Sirius, the brightest star in the night sky, tagging along behind it.
The SOHO spaceborne solar observatory today captured comet Lovejoy in its field of view for the first time, indicating that the icy body is on its final destructive plunge towards the Sun.
ADDITIONAL RESEARCH DONE FOR DECEMBER 14, 2011
A gas cloud on its way towards the super-massive black hole in the Galactic Centre
Authors: S. Gillessen, R. Genzel, T. K. Fritz, E. Quataert, C. Alig, A. Burkert, J. Cuadra, F. Eisenhauer, O. Pfuhl, K. Dodds-Eden, C. F. Gammie, T. Ott
(Submitted on 14 Dec 2011)
Abstract: Measurements of stellar orbits provide compelling evidence that the compact radio source Sagittarius A* at the Galactic Centre is a black hole four million times the mass of the Sun. With the exception of modest X-ray and infrared flares, Sgr A* is surprisingly faint, suggesting that the accretion rate and radiation efficiency near the event horizon are currently very low. Here we report the presence of a dense gas cloud approximately three times the mass of Earth that is falling into the accretion zone of Sgr A*. Our observations tightly constrain the cloud's orbit to be highly eccentric, with an innermost radius of approach of only ~3,100 times the event horizon that will be reached in 2013. Over the past three years the cloud has begun to disrupt, probably mainly through tidal shearing arising from the black hole's gravitational force. The cloud's dynamic evolution and radiation in the next few years will probe the properties of the accretion flow and the feeding processes of the super-massive black hole. The kilo-electronvolt X-ray emission of Sgr A* may brighten significantly when the cloud reaches pericentre. There may also be a giant radiation flare several years from now if the cloud breaks up and its fragments feed gas into the central accretion zone.
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Alien Captured At Russian Machine Plant? 2011by StephenHannardADGUK277,654 views
UPDATE: S PER SOHO.NASA- December 16, 12:00UT: Comet Lovejoy survives!!! Somehow it survived being immersed in the several million-degree solar corona for almost an hour and has now re-emerged back into the views of the LASCO and SECCHI coronagraphs, almost as bright as before! The only noteable exception is that it appears to have lost its tail, more to follow....
CanDoTina 2 months ago