Current comet magnitude parameters

Standard parameters:

Comet	 	Update	 H1	 K1
	  2P	071201	10.9	 8.8
	  2P	101103	10.2U	 6.4
	  4P    071201   9.4U	 6.9
	  6P	090118	Outburst
	  9P	050901	 6.8U	23.1
	 15P	080901	 8.5U	22.6
	 16P	120229	11.3	[10]
	 19P	090328	 6.4U	13.2
	 21P	050731	 8.5U	19.9
	 21P	130115	 5.4U	30.8
	 22P    091205	 8.3U	 8.9
         24P	120229	 7.5	19.9
	 32P	050420	 6.9U	16.7
	 37P	991016	10.6U	11.8
	 43P	040428	 6.5	16.2
	 44P	120229	 9.2	[10]
	 45P	111128	12.9U	20.3
	 46P	080421	 8.5U	20.5
	 47P	120229	 5.3	[15]
	 51P	120229	10.4	[10]
	 52P	 	 6.8	[15]
	 55P	 	 8.5	26.7
	 59P	991231	 7.8U	[15]
	 62P	050420	 8.8U	19.1
	 63P	000411	10.6U	 7.5
	 63P	130430	 7.5U	12.8
         65P	101103	 7.9U	 6.6
	 67P	090328	 6.7U	25.5
	 69P		 8.1 	 7.5
	 71P	070102	 9.7	 7.9
	 73P	070102	11.3	 5.5			
	 74P	120229	 4.9	[10]
	 78P    120103	-2.7U	40.7
	 81P	100818	 8.7U	 6.9
	 82P	120229	10.4	[10]
	 84P	991231	10.8U	[15]
	 88P    091205	 1.8U	42.6
	 93P	071118	 8.7	18.5
	 96P	071201	11.9U	10.4
	103P		 8.5	18.4
	103P	Linear
	104P		10.5	11.0
	106P	000118	12.7U	 [5]
	110P	120229	 6.9	[10]
	114P    000411	 8.9U	28.9
	116P	090818	-1.3U	32.4
        128P		 6.3	[15]
        132P		10.3	[15]
	141P	000411	13.6U	11.8
	144P	090607	 4.3U	32.1
	161P	050731	 9.0	[10]
	168P	130115	10.3U	 6.7
	177P	070102	 9.1	16.8
	185P	120925	10.7U	19.6
	193P	120229	11.4	[10]
	201P	120229	12.7	[10]
	204P	120229	 9.9	[10]
	210P    090328	12.9U	 5.3
	216P	120229	12.4	[10]
	217P	091205	10.3U	12.3
	222P	090928	16.4U	[15]
	246P	130329	 3.0U	[15]
	260P	121222	10.7U	[10]
	262P    130115	 9.4U	[15]
1995 O1		000411	-0.64	 7.53
1997 BA6	001003	 4.6U	 9.8
1997 D1			 8.0	[7.5]
1997 J2			 5.1	 5.8
1997 T1			 6.6	16.4		
1998 H1			11.0	 5.0
1998 J1			 6.2	 6.3
1998 M5		000411	 6.0U	10.2
1998 P1		991006	 6.7U	 9.9
1998 T1		990830	10.2U	 4.5
1998 U5		9905xx	 7.8U	19.6
1998 W1			11.7	[10]
1999 H1		000411	 6.7U	11.5
1999 H3		000630	 4.1U	12.5
1999 J2		011007	-1.2U	13.4
1999 J3		000411	 9.0U	11.8
1999 K5		001127	 6.7U	 8.2
1999 K8		001127	-2.8U 	20.8
1999 L3		000411	 2.7U	29.9
1999 N2		000401	 8.6U	 7.7
1999 S3		000401	 0.7U	39.8
1999 S4		000816	 8.6	 4.4
1999 T1		011007	 6.3U	 9.4
1999 T2		011007	 6.5U 	 8.2
1999 U4		020414	 6.9U	 4.6
1999 Y1		011219	 8.1U	 4.3
2000 SV74	020414	 8.0U	 3.9
2000 W1		010312	10.8U	12.7
2000 WM1	020601	 7.1U	10.6
2001 A2		011007	 7.3U	10.6
2001 HT50	040619	 6.5	 [5]
2001 K5		020619	 5.1 	 5.0
2001 MD7	020414	11.3U	[10]
2001 OG108	020414	10.2U	 5.9
2001 Q2		011202	10.7U	15.5
2001 Q4		050208	 5.7U	 6.6
2001 Q6		020414	 5.5U	41.0
2001 RX14       030519	 7.9U	 7.8
2002 C1		020601	 6.6U	 8.5
2002 E2		020414	 8.0U	[10]
2002 F1		020601	10.6U	18.1
2002 G3		020414	20.7U	22.1
2002 O7		040619	 8.9	 4.2
2002 T7		041213	 5.5U	 6.3
2002 V1		030407	 7.2	 9.5
2002 X5		030407	 7.2	 6.7
2002 Y1		040619	 6.5	 9.5
2003 H1		040619	 4.8	[15]
2003 K4		050420	 4.0U	11.1
2003 T3		040919	 6.6U	 6.9
2003 T4		050420	 7.8U	 6.6
2004 F4		040703	 8.0	 8.1
2004 H6		040718	 7.4	13.2
2004 Q1		050312	 1.5U	27.5
2004 Q2		050901	 5.2U	 9.3
2004 R2		040928	10.1U	 8.2
2005 A1		050731	 8.5U	10.2
2005 E2		060410	 6.8U	 8.5
2005 L3		090818	 5.9U	 [5]
2005 N1		050731	 8.5U	22.9
2006 A1		070102	 7.7	 8.3
2006 L1		070125	 6.7U	15.8
2006 L2		070102	 5.1	14.8
2006 M4		070102	 5.8U	 9.1
2006 OF2	090607	 6.7U	 6.3
2006 P1		071201	 4.4	 9.7
2006 Q1		090328	 4.8U	10.5
2006 S3		130430	-5.6U	19.9
2006 VZ13	071201	 8.2	11.1
2006 W3		101218	-0.7U	14.6
2007 E1		071201	 6.9	25.9
2007 E2		071201	 9.1	 7.6
2007 G1		080901	 0.3U	[20]
2007 H1		071201	 9.0	[10]
2007 N3		090607	 5.5U   10.5
2007 Q3		091205	 2.0U	13.2
2007 T1		080320	 7.4	13.4
2007 W1		081022	 8.6U	 9.6
2008 A1		090328	 5.9U	 8.7
2008 C1		080508	 6.9U	21.3
2008 Q3		090928	-1.1U	32.5
2008 J1		081124	 5.1U	17.6
2008 T2		091205	 6.5U	11.9
2009 F6		090928	 6.8U	[12]
2009 G1		090818	 7.6U	 9.3
2009 K5		101103	 6.5U	 6.3
2009 L2		090818	14.5U	[5]
2009 P1		130115	 4.4U	 6.8
2009 R1		100818	 6.7	 7.6
2009 Y1		101218	 3.3U	18.5
2010 G2		120719	 7.8U	 5.0
2010 S1		130430	 5.4U	[5]
2010 X1		110722	 8.1	 9.6
2011 A3		111223	-3.9U	28.6
2011 C1		111223	 9.4U	 4.3
2011 F1		130430	 6.9U	 5.0
2011 L4		130430	 5.2	 9.3
2011 M1		111223	 9.5U	17.2
2011 R1		130329	 5.5U	11.5
2011 UF305	130115	-2.6U	34.2
2011 W3		130115	11.4U	17.5
2012 A2		130430	 3.4U	[10]
2012 F6		130430	 5.1    10.0
2012 J1		130115	 3.2U	[15]
2012 K5		130115	10.1U	 6.0
2012 L2		130430	 7.3U	 9.8
2012 S1		130219	 5.3	[7.5]
2012 T5		130115	10.0	15.3
2012 V4		130115	 9.5U	[15]
The magnitude of the comet can be obtained from : m = H1 + 5 log d + K1 log r
For comets currently under observation a U after the H parameter indicates that the observed magnitudes have not been corrected for aperture. This gives a better estimate for the current magnitude of the fainter comets.

Linear parameters

Comet		Update	H1	L1	dT
          6P    081001  Outburst
	  8P    080421   6.8U    0.0429 -27.1
	 10P	101218	 9.4U	 0.0152	-28
         41P    120229	 6.1     0.102   18
         46P    021020   9.5U    0.0273 -31.7
	 52P		10.9	 0.0299	 28.5
	 67P	090607	 7.7	 0.0329	-49
	 71P	070102	 9.1	 0.0400	-34.5
	 78P	050420	10.4U	 0.0100	-60
	 78P    130115	 8.9U	 0.0156	-33
         88P    040718	12.0	 0.0425 -10.4
	 96P	130115	 9.7U	 0.0501	-16
	103P	111223	 9.0U	 0.0416	-26
	141P	000118	11.8U	 0.0379 -21.2
	185P	130115	 9.8	 0.0375	-18
	217P	120229	 9.4	 0.0180 -32
	260P	130115	13.2	 0.0145	-17
	273P	130219	 6.2	 0.0753	-15
1998 K5			16.5	 0.0201	-55.7
1998 U3			 9.8	 0.0151	 46.0
2007 F1		071201	 6.3	 0.0508	 10.3
2007 Q3		100610	 6.2	 0.0156	-44
2009 E1		090704	 7.0	 0.0719	-11.6
2009 K5		101218	 7.0U	 0.0172	-32
The magnitude of the comet can be obtained from : m = H1 + 5 log d + L1 abs(t - T + dT)
if L1 is +ve the comet brightens towards perihelion, if dT is +ve the comet is brightest before perihelion.

Where there are insufficient observations to fully determine the r coefficient a value for K is assumed and given in [ ].