Comet C/1999 S4 (LINEAR)

1999:
Nov. 08.43: m1 = 14.7:(+/-0.2) Dia. 0.4' , DC = 4 , 169x256 L, Dilli. (HI)
Nov. 14.51: m1 = 14.6 (+/-0.1) Dia. 0.5' , DC = 5 , 169x256 L, Dilli. (HI)
Nov. 15.46: m1 = 14.2 (+/-0.1) Dia. 0.4' , DC = 6 , 169x256 L, Dilli. (HI)
Nov. 16.49: m1 = 14.4 (+/-0.1) Dia. 0.5' , DC = 6 , 169x256 L, Dilli. (HI)
Nov. 27.32: m1 = 14.3:(+/-0.2) Dia. 0.4' , DC = 5 , 169x256 L, Dilli. (HI)
Nov. 28.34: m1 = 14.3 (+/-0.2) Dia. 0.4' , DC = 5 , 169x256 L, Dilli. (HI)
Nov. 29.33: m1 = 14.3 (+/-0.2) Dia. 0.5' , DC = 5 , 169x256 L, Dilli. (HI)
Dec. 01.30: m1 = 14.3 (+/-0.2) Dia. 0.6' , DC = 5 , 169x256 L, Dilli. (HI)
Dec. 05.32: m1 = 14.2 (+/-0.2) Dia. 0.5' , DC = 5 , 169x256 L, Dilli. (HI)
Dec. 06.34: m1 = 14.3 (+/-0.1) Dia. 0.6' , DC = 5 , 169x256 L, Dilli. (HI)
Dec. 08.46: m1 = 14.3 (+/-0.2) Dia. 0.6' , DC = 5 , 169x256 L, Dilli. (HI)
Dec. 14.40: m1 = 14.2 (+/-0.3) Dia. 0.6' , DC = 6 , 169x256 L, Dilli. (HI)
Dec. 16.46: m1 = 14.3 (+/-0.1) Dia. 0.6' , DC = 5 , 169x256 L, Dilli. (HI)
Dec. 30.34: m1 = 14.3 (+/-0.1) Dia. 0.6' , DC = 5 , 169x256 L, Dilli. (HI)
2000:
Jan. 12.35: m1 = 14.3 (+/-0.1) Dia. 0.5' , DC = 5 , 169x256 L, Dilli. (HI)
Jan. 23.25: m1 = 14.4 (+/-0.1) Dia. 0.5' , DC = 5 , 169x256 L, Dilli. (HI)
Jan. 25.26: m1 = 14.3 (+/-0.1) Dia. 0.6' , DC = 5 , 169x256 L, Dilli. (HI)
Jan. 26.29: m1 = 14.2 (+/-0.2) Dia. 0.7' , DC = 6 , 169x256 L, Dilli. (HI)
Jan. 29.29: m1 = 14.1 (+/-0.2) Dia. 0.6' , DC = 5 , 169x256 L, Dilli. (HI)
Jan. 30.31: m1 = 14.2 (+/-0.2) Dia. 0.6' , DC = 5 , 169x256 L, Dilli. (HI)
Feb. 03.31: m1 = 14.3 (+/-0.1) Dia. 0.6' , DC = 5 , 169x256 L, Dilli. (HI)
Feb. 05.27: m1 = 14.2 (+/-0.2) Dia. 0.7' , DC = 4 , 169x256 L, Dilli. (HI)
Feb. 06.32: m1 = 14.3 (+/-0.1) Dia. 0.6' , DC = 5 , 169x256 L, Dilli. (HI)
Feb. 08.30: m1 = 14.1 (+/-0.2) Dia. 0.6' , DC = 4 , 169x256 L, Dilli. (HI)
Feb. 23.26: m1 = 13.9 (+/-0.2) Dia. 0.9' , DC = 4 , 84x256 L, Dilli. (HI)
Feb. 26.27: m1 = 13.9 (+/-0.2) Dia. 1' , DC = 4 , 84x256 L, Dilli. (HI)
Feb. 29.27: m1 = 13.8 (+/-0.2) Dia. 1.0' , DC = 3 , 84x256 L, Dilli. (HI)
Mar. 04.26: m1 = 13.8 (+/-0.2) Dia. 1.2' , DC = 3 , 84x256 L, Dilli. (HI)
Mar. 05.25: m1 = 13.8 (+/-0.2) Dia. 1.0' , DC = 3 , 84x256 L, Dilli. (HI)
May 10.63: m1 > 10.0 (Dia. 1')(Stellar limit 11.4) 169x256 L, Dilli. (HI)
May 15.62: m1 = 12.1:(+/-0.3) Dia. 1' , DC = 3 , 169x256 L, Koko-H.(HI) (Stellar limit 12.6 - to confirm)
May 17.63: m1 = 11.3:(+/-0.4) Dia. 1.5' , DC = 4 , 84x256 L, Koko-H.(HI) (Stellar limit 12.3 - to confirm -- in (too) strong twilight)
May 18.62: m1 = 11.6:(+/-0.2) Dia. 1.5' , DC = 5 , 84x256 L, Koko-H.(HI) (Stellar limit 12.3 - full moon)
May 23.62: m1 = 11.2:(+/-0.3) Dia. 2.0' , DC = 3 , 84x256 L, Koko-H.(HI) (Stellar limit 12 - clouds then twilight !!)
May 25.61: m1 = 11.3 (+/-0.2) Dia. 1.9' , DC = 5 , 84x256 L, Dilli. (HI)
May 29.61: m1 = 11.0 (+/-0.2) Dia. 2.0' , DC = 5 , 42x256 L, Dilli. (HI)
May 30.61: m1 = 10.9 (+/-0.1) Dia. 2.5' , DC = 6 , 84x256 L, Koko-H.(HI)
June 01.61: m1 = 10.8:(+/-0.2) Dia. 2.5' , DC = 5 , 42x256 L, Koko-H.(HI)
June 03.59: m1 = 10.5 (+/-0.2) Dia. 3.0' , DC = 6 , 42x256 L, Dilli. (HI)
June 04.60: m1 = 10.2 (+/-0.2) Dia. 2.8' , DC = 6 , 42x256 L, Dilli. (HI)
June 06.59: m1 = 10.2 (+/-0.2) Dia. 3.0' , DC = 6 , 42x256 L, Dilli. (HI)
June 09.59: m1 = 10.1 (+/-0.1) Dia. 3.0' , DC = 6 , 42x256 L, Dilli. (HI)
June 10.60: m1 = 9.9 (+/-0.1) Dia. 3.5' , DC = 6 , 42x256 L, Dilli. (HI)
June 13.59: m1 = 9.8 (+/-0.2) Dia. 3.5' , DC = 5 , 42x256 L, Dilli. (HI)
June 26.59: m1 = 8.7 (+/-0.1) Dia. 4.0' , DC = 6 , 42x256 L, Dilli. (HI)
June 28.57: m1 = 8.9 (+/-0.1) Dia. 3.5' , DC = 7 , 42x256 L, Honol. (HI)
July 08.08: m1 = 7.9 (+/-0.1) Dia. 6' , DC = 6 , 7x50 B, Lezeaux(Fr)
July 18.92: m1 = 7.5:(+/-0.3) Dia. 5' , DC = 7 , 42x256 L, Versai.(Fr) (Stellar limit 12.5 - full moon, haze, light pollution)
July 20.91: m1 = 7.0 (+/-0.2) Dia. 8' , DC = 5 , 7x50 B, Ablis (Fr)
July 20.92: m1 = 7.2 (+/-0.2) Dia. 5' , DC = 6 , 42x256 L, Ablis (Fr)
July 21.92: m1 = 6.5 (+/-0.1) Dia. 8' , DC = 6 , 7x50 B, Versai.(Fr)
July 21.92: m1 = 6.7 (+/-0.2) Dia. 3' , DC = 8 , 42x256 L, Versai.(Fr)
July 22.92: m1 = 6.8:(+/-0.3) Dia. 4' , DC = 8 , 42x256 L, Versai.(Fr)
July 22.94: m1 = 6.4:(+/-0.2) Dia. 5' , DC = 6 , 7x50 B, Versai.(Fr)
July 25.28: m1 = 6.7 (+/-0.1) Dia. 7' , DC = 7 , 7x50 B, Hale-P.(HI)
July 26.29: m1 = 6.4 (+/-0.2) Dia. 8' , DC = 5 , 7x50 B, MaunaK.(HI)
July 27.28: m1 = 7.2 (+/-0.1) Dia. 8' , DC = 5 , 7x50 B, MaunaK.(HI)
July 28.28: m1 = 7.6 (+/-0.1) Dia. 9' , DC = 4 , 7x50 B, MaunaK.(HI)
July 29.26: m1 = 7.7 (+/-0.1) Dia. 8' , DC = 3 , 7x50 B, MaunaK.(HI)
July 30.27: m1 = 7.9 (+/-0.2) Dia. 9' , DC = 3 , 7x50 B, MaunaK.(HI)
July 31.26: m1 = 8.0 (+/-0.1) Dia. 9' , DC = 3 , 7x50 B, MaunaK.(HI)
Aug. 01.28: m1 = 8.3 (+/-0.2) Dia. 7' , DC = 3 , 7x50 B, MaunaK.(HI)
Aug. 02.28: m1 = 8.5 (+/-0.2) Dia. 8' , DC = 2 , 7x50 B, MaunaK.(HI)
Aug. 03.28: m1 = 8.8 (+/-0.1) Dia. 10' , DC = 1 , 7x50 B, MaunaK.(HI)
Aug. 04.27: m1 = 9.1 (+/-0.2) Dia. 8' , DC = 1 , 7x50 B, MaunaK.(HI)
Aug. 05.27: m1 = 9.2 (+/-0.1) Dia. 7' , DC = 1 , 7x50 B, MaunaK.(HI)

Nov 8.32 - 8.43: Very likely seen (with motion in 2h40/no background star) , also quite difficult. Nov.14,15,16: faint but clearly seen.
2000:
May 18.62: Still very low contrast but about sure this time.
May 30.61: Comet now easily visible;3' tail in PA=280.
June 03.60: 4.0' tail in PA=270; m2=13.2+-0.2 (169x256 L)
June 04.61: 4.0' tail in PA=270; m2=13.2+-0.2 (169x256 L)
June 06.61: 4.5' tail in PA=275; m2=13.0+-0.2 (169x256 L)
June 09.61: 4.5' tail in PA=270; m2=13.5+-0.2 (169x256 L)
June 10.61: 6.0' tail in PA=270; m2=13.4+-0.1 (169x256 L)
June 13.61: 6.0' tail in PA=270; m2=13.2+-0.1 (169x256 L)
June 26.61: 18' tail in PA=260; m2=11.9+-0.2 (169x256 L)
June 28.59: 15' tail in PA=260; m2=11.8+-0.2 (169x256 L)
July 18.94: >12' tail in PA=320; m2=12.0+-0.2 (169x256 L) (hazy polluted sky)
July 20.94: 28' tail in PA= 9; m2=12.2+-0.2 (169x256 L)
July 21.91: >12' tail in PA= 30; m2= 9.9+-0.2 (169x256 L) - outburst!
July 22.93: >18' tail in PA= 50; m2=10.0+-0.1 (169x256 L) (Cirrus)
July 25.28: 1.5d tail in PA= 60 (7x50B); m2=11.6+-0.3 (70x355 SCT)
July 26.29: 1.1d tail in PA= 65 (7x50B);
July 27.28: 1.2d tail in PA= 75 (7x50B);
July 28.28: 0.6d tail in PA= 80 (7x50B);
July 29.26: 0.6d tail in PA=100 (7x50B);
July 30.27: 0.4d tail in PA=100 (7x50B) (ion tail);
July 31.27: 0.4d tail in PA= 90 (7x50B) (dust tail);
Aug. 01.28: 0.8d tail in PA= 95 (7x50B);
Aug. 02.29: 0.4d tail in PA= 95 (7x50B);

Rh and Delta (30/10/1999->25/08/2000) ... [ps file]
Light curve:
m1:8/11/1999-05/08/2000 ... [ps file]
mh:8/11/1999-05/08/2000 ... [ps file]
mh:8/11/1999-03/08/2000 : With interpretation based on correlation laws in terms of CO and Water production rates;
See the drop in mh, starting 50 days before perihelion, and the final outburst around perihelion!
Images:

10.6 June, 25.6cm L 169x, 6'x9' - North up -	13.6 June, 25.6cm L 169x, 6'x9'	20.9 July, 25.6cm L 42x, 36'x36' South up
20.9 July, 25.6cm L 169x, 4x4' - South up	21.9 July, 25.6cm L 169x, 4x4'	22.9 July, 25.6cm L 169x, 4x4'

27-July-2000 6:25 UT 5min. picture 135mm F/D 2.5