Current comet magnitudes (September 5) and observable region (September 1)
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Comet Magnitude Trend Observable When visible Last visual observation
LINEAR (2012 V2) 9 fade 15 N to 75 S dawn 2013 August
Borisov (2013 N4) 9 fade Poor elongation 2013 August
Lemmon (2012 F6) 11 fade 65 N to 0 S all night 2013 September
ISON (2012 S1) 11.5 bright 50 N to 0 S dawn 2013 September
PanSTARRS (2011 L4) 12.5 fade 65 N to 10 S evening 2013 September
LINEAR (2011 F1) 12 ? fade 15 N to 80 S best morning 2012 November
LINEAR (2010 S1) 12.5 steady 65 N to 35 S best evening 2013 August
McNaught (2013 J2) 12.5 fade 65 N to 55 S best evening 2013 August
246P/NEAT 12.5 ? fade 25 N to 80 S best evening 2013 March
LINEAR (2012 L2) 13 ? fade 45 S to 80 S dawn 2013 May
LINEAR (2012 A2) 13 ? fade 65 N to 25 S best morning 2012 November
29P/Schwassmann-Wachmann 13 ? varies 5 N to 70 S evening 2013 June
102P/Shoemaker 13 ? steady 65 N to 40 S best morning Not yet observed
154P/Brewington 14 bright 55 N to 80 S midnight Not yet observed
2P/Encke 14 bright 65 N to 30 S best morning Not yet observed
2012 S1 (ISON) was observed visually by Juan Jose Gonzalez on September 1 at 11.2. The recovery has reduced the error bars on the likely perihelion magnitude a bit, but they are still large. It will probably get brighter than Venus, but it could be as faint as 8th magnitude.