2013-10-12

ISON is getting brighter...

...and still shows no signs of an "impending demise". After a painful 10 day shutdown (as a result of pertinacious cloud cover, which reminds me of my real problem once ISON makes it's perihelion: the terrible northern European weather in December) I managed to image the comet this morning. It looks considerably brighter and bigger than before.

Artyom Novichonok estimated "his" comet's brightness at 10,2mag this morning, the diameter of it's coma at 4,6' and the tail at 15'. My images show a 10' long tail. As always, I used simple equipment (a 8" f/4 Newtonian and a Canon EOS 450Da DSLR). Skyglow was reduced with an Astronomik CLS filter.

Comet C/2012 S1 (ISON) on Oct. 12, 03:00-04:24 UTC. Jan Hattenbach/Sternwarte Aachen

The inverted and enhanced imaged clearly shows a 10' long tail and a fairly bright coma.

Three images, taken with exactly the same equipment between September 28 and October 12. The comet has considerably increased both in brightness and size.
Although still not an eye-catching object in the telescope, ISON is currently easy to find: Mars is just 1,5° away from the comet. ISON will remain a telescopic object on the morning sky for the rest of October, and will hopefully be visible with binoculars in November.

The "impending demise" should be off the table, one might think. Ignacio Ferrín however keeps believing the comet is disintegrating, called for "orange alert" and is drawing some "red lines" (whatever that means). Frankly, I cannot see on what ground his assessment is based, since all the world is watching ISON obvousily gaining brightness, not loosing it. [Update, Oct. 14: Ferrín updated his secular light curve with recent observational data, acknowledging the comet is getting brighter.] In the meantime, Zdenek Sekanina has published a different, down-to-earth view on ISON's prospects until perihelion compared to other comets (and will give updates on a weekly basis). Also read Karl Battams recent post on this.

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