1 December:The end of a comet? According to blog posts from the NASA SOHO web site Comet ISON has faded considerably and there may be nothing left but pieces of the nucleus and dust.
29 November: Comet ISON has survived perihelion and should become visible as the second animated graphic below shows. However how bright or what it will look like we will know about in a couple of days.
This animated graphic directly below is made from images taken by the SOHO satellite’s coronagraph, a telescope with an occulting disk at the front end to ‘eclipse’, block, the Sun. In this graphic the dark disk represents the occulting disk and the white circle is the disk of the Sun. Comet ISON appears from the right side and as it becomes blocked by the occulting disk the tail of the comet is still visible. After perihelion the comet reappears on the other side of the Sun with a more fan-shaped tail.’
This graphic comes from the Space Weather website. Click here for more information about a coronagraph.
Click on graphic to see an animated full size version.
28 November, at 23 UT (5 pm CST) Comet ISON will reach perihelion, its closest approach to the Sun. If the comet survives ‘swinging’ around the Sun and passing within less than 1 million miles from the Sun it will reappear on the Earth side of the Sun. From perihelion onward the comet will be outbound from the inner solar system and by 26 December will be at its closest to Earth – approximately 0.426 AU (63,728,693 km or 39,599,174 miles)
Superstitious? The banner graphic at the top of the page shows Comet ISON as may appear on Friday 13 December. If my software is simulating the view correctly then the comet on that date will still be showing a tail reaching to Gemma, the ‘crown jewel’ in Corona Borealis the Northern Crown, and Comet ISON should be between 5th and 6th magnitude. At that magnitude range the comet will be visible to the naked-eye under dark skies and with optical assistance should be a great sight.
Click here to view or download the animated graphic from the Huffington Post page on Google+.
Click here to go to the Qué tal in the Current Skies web site for more observing information for this month.