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Old 07-11-2011, 11:20 AM
Rob_K
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Rob_K is offline
 
Join Date: Oct 2006
Location: Bright, Vic, Australia
Posts: 2,187
As far as I can see, closest approach will be 23:28, 8 Nov UT. Immaterial really because it's approaching Earth from the sunward side and will not be optically visible from anywhere on Earth at that time. It will start to become visible a few hours after the close approach as it enters 'dark skies'. It will be brightest at mag 11.1 at around 4:30 9 Nov UT, or 3:30pm AEDST (UT+11), again in daylight for us. This is worked out on the phase versus the distance from us, and doesn't coincide with closest approach.

So the optimum time will be after twilight on 9 Nov. It will be about 20-deg away from the big gibbous Moon then, and will close in on it as the night progresses. It will be gradually fading, from mid mag 11s to around mag 12. The next night it will have faded right off into the mag 14s so there will only be one realistic opportunity, on the night of Wed 9 November in Australia. And a poor one because of the Moon.

I only have one query - the JPL ephemeris shows an 'instantaneous jump' from RA 23h to RA 00h at around 07:55 UT on the 9th. What's going on?

Cheers -
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