Quote:
Originally Posted by JB80
Thanks Ian for the reply,
I'm going on the idea that we might be living in France by that time so as far as I can tell the easiest option would be a drive up to the Normandy region on the coast overlooking the channel islands. It seem to be one of the more LP free regions. Depending on what other plans we might have.
The other thing I have just considered is stellarium predicts(the only info I had at hand) Ison to be +6mag on November the 3rd, there is also a total solar eclipse on that day so I wonder if ir might be visible during totality or even able to be captured on camera with a wide enough lense to get the eclipse and comet in.
I imagine it'd need to be a combination of exposures to work.
Just an idea I had.
I wonder what Gabon is like in November?
Hopefully some news soon re the meteor shower, that would be a nice bonus.
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I'm picking up a number of posts including Jarrod's.
Using solar filters
As Rob pointed out solar filters are a no go on the comet. Even if Comet C/2012 S1 (ISON) reached a magnitude of -4, an ND4 solar filter drops the brightness by 10 magnitudes and and ND5 filter drops it 12.5 magnitudes. So the Sun at magnitude -26 with an ND5 filter drops down to mag -13.5 - about four times as bright as a full moon but the comet drops down to mag 8. Would you see a mag 8 comet next to a full Moon let alone something as four times as bright as a usual full moon?
However you could try using a bare piece of filter as an occulting device. This has the advantage that you can see where the sun is with respect to the edge so that the sun is unlikely to peek out and surprise you. Nonetheless extreme caution will be necessary to avoid exposure and I wouldn't try this with optical aids, just naked eye. Another possibility is to use a tall building as an occulting device. Stand just near the edge of the shadow with the comet exposed, Sun hidden.
Observations during Solar Eclipse
Forget it. Based on current predictions, the comet will be around magnitude 6 during next November's eclipse. This is unlikely to be visible except with telescopic aid and frankly there are more interesting things to look at during a solar eclipse than a mag 6 comet. I have picked up mag 6.5 stars in the corona in my photos in the past but the comet is at 50 degrees elongation so it's not likely to pop up in anyone's photos by chance. On Nov 3rd, from the eclipse zone, the comet will be much more easily observed in the completely dark pre-dawn sky. I'll be on a yacht crossing the Atlantic observing the eclipse and finishing in Barbados on the 13th.
However, if like me, you want to go to the eclipse anyway, the geometry just north of the equator is a bit more favourable than the southern hemisphere. Probably not warranting a special trip but if you'll be there anyway, why not? The slight north equatorial latitude results in a short twilight and inclination of the celestial sphere to the horizon pushes the comet higher above the horizon. I am toying with the idea of spending another 2 weeks in the Caribbean touring around (something I wanted to do anyway) and observing the comet from the West Indies, Jamaica and Cuba then flying home around 28/29th. The air at 40000 ft is pretty clear in the unlikely event I can get a good clear window I might manage a glimpse.
The weather in Gabon is pretty bad.
One possibility here at home is to look into a group chartering of an aircraft and flying high to get above all the crud in the atmosphere. I chartered a DASH 8 for the last eclipse. We flew a big group of people out to the Gulf of Carpentaria. It's pretty easy to do and wouldn't cost too much if you were just going to go up and down for a short flight without covering too much distance. A Dash 8 with its high wing is not the aircraft for this. An 8-10 seater low wing aircraft like a Cessana 402c will get you up to 10000 ft without too many layers of glass or plastic between you and the sun. Choose the aircraft carefully. Inspect the windows first. You also have to make the flight early or late so the sun & comet is low enough altitude to be observed out of the windows.
Joe