Comet 21P/Giacobini-Zinner

1998:
June 30.46: m1 = 14.6 (+/-0.3) Dia. 0.4', DC = -, 169x256 L, Dilli. (HI)
July 25.43: m1 = 14.0 (+/-0.2) Dia. 0.5', DC = 5, 169x256 L, Silva (HI)
July 26.32: m1 = 14.0 (+/-0.2) Dia. 0.5', DC = 6, 169x256 L, Dilli. (HI)
July 29.41: m1 = 13.7 (+/-0.2) Dia. 0.6', DC = 5, 169x256 L, Dilli. (HI)
July 30.45: m1 = 13.6 (+/-0.2) Dia. 0.6', DC = 5, 169x256 L, Dilli. (HI)
Aug. 11.31: m1 = 13.3 (+/-0.2) Dia. 1' , DC = 4, 169x256 L, Koko-H.(HI)
Aug. 12.30: m1 = 13.3 (+/-0.2) Dia. 1.0', DC = 5, 169x256 L, Koko-H.(HI)
Aug. 13.33: m1 = 13.1 (+/-0.1) Dia. 1.0', DC = 5, 169x256 L, Koko-H.(HI)
Aug. 15.30: m1 = 12.2 (+/-0.2) Dia. 1.5', DC = 4, 84x256 L, Dilli. (HI)
Aug. 16.32: m1 = 12.1 (+/-0.2) Dia. 1.2', DC = 5, 84x256 L, Dilli. (HI)
Aug. 19.32: m1 = 12.3 (+/-0.2) Dia. 1.3', DC = 4, 84x256 L, Koko-H.(HI)
Aug. 20.32: m1 = 12.2 (+/-0.2) Dia. 1.5', DC = 5, 84x256 L, Dilli. (HI)
Aug. 24.31: m1 = 12.5 (+/-0.2) Dia. 1.3', DC = 5, 84x256 L, Dilli. (HI)
Aug. 28.36: m1 = 11.6 (+/-0.2) Dia. 2.0', DC = 3, 42x256 L, Dilli. (HI)
Sep. 08.25: m1 = 11.3 (+/-0.2) Dia. 1.5', DC = 4, 42x256 L, Kahe-P.(HI)
Sep. 11.27: m1 = 11.2 (+/-0.2) Dia. 2.0', DC = 5, 42x256 L, Dilli. (HI)
Sep. 13.28: m1 = 11.0 (+/-0.2) Dia. 2.0', DC = 6, 42x256 L, Dilli. (HI)
Sep. 15.33: m1 = 11.1 (+/-0.2) Dia. 1.8', DC = 6, 42x256 L, Dilli. (HI)
Sep. 18.29: m1 = 11.0 (+/-0.1) Dia. 2.5', DC = 5, 42x256 L, Dilli. (HI)
Sep. 19.32: m1 = 10.9 (+/-0.2) Dia. 2.5', DC = 5, 42x256 L, Silva (HI)
Sep. 20.28: m1 = 10.8 (+/-0.2) Dia. 2.5', DC = 6, 42x256 L, Dilli. (HI)
Sep. 24.32: m1 = 10.4 (+/-0.1) Dia. 3.0', DC = 3, 42x256 L, Koko-H.(HI)
Sep. 27.27: m1 = 10.5 (+/-0.2) Dia. 3.0', DC = 4, 42x256 L, Honol. (HI)
Oct. 08.25: m1 = 10.2 (+/-0.2) Dia. 3.5', DC = 5, 42x256 L, Dilli. (HI)
Oct. 09.25: m1 = 10.0 (+/-0.1) Dia. 4.0', DC = 5, 42x256 L, Dilli. (HI)
Oct. 18.27: m1 = 9.6 (+/-0.2) Dia. 4.0', DC = 5, 42x256 L, Dilli. (HI)
Oct. 20.26: m1 = 9.7 (+/-0.2) Dia. 3.5', DC = 6, 42x256 L, Dilli. (HI)
Oct. 23.24: m1 = 9.3 (+/-0.2) Dia. 4.0', DC = 6, 42x256 L, Dilli. (HI)
Oct. 23.25: m1 = 9.1 (+/-0.2) Dia. 5' , DC = 5, 10x50 R, Dilli. (HI)
Oct. 24.28: m1 = 9.3 (+/-0.2) Dia. 4.0', DC = 6, 42x256 L, Dilli. (HI)
Oct. 24.29: m1 = 9.2 (+/-0.2) Dia. 5' , DC = 5, 10x50 R, Dilli. (HI)
Oct. 29.24: m1 = 8.9 (+/-0.1) Dia. 8' , DC = 5, 7x50 B, MaunaK.(HI)
Oct. 30.30: m1 = 8.8 (+/-0.2) Dia. 10' , DC = 3, 7x50 B, MaunaK.(HI)
Nov. 07.23: m1 = 9.2 (+/-0.2) Dia. 4.5', DC = 6, 42x256 L, Dilli. (HI)
Nov. 14.27: m1 = 8.8 (+/-0.2) Dia. 10', DC = 4, 7x50 B, MaunaK.(HI)
Nov. 14.28: m1 = 9.0 (+/-0.1) Dia. 6' , DC = 4, 20x80 B, MaunaK.(HI)
Nov. 15.24: m1 = 9.4 (+/-0.2) Dia. 5' , DC = 4, 7x50 B, MaunaK.(HI)
Nov. 15.24: m1 = 9.4 (+/-0.2) Dia. 5' , DC = 4, 20x80 B, MaunaK.(HI)
Nov. 17.28: m1 = 9.6 (+/-0.2) Dia. 3.5', DC = 6, 42x256 L, Dilli. (HI)
Nov. 21.24: m1 = 9.8 (+/-0.2) Dia. 4.0', DC = 6, 42x256 L, Dilli. (HI)
Nov. 21.29: m1 = 9.4 (+/-0.2) Dia. 8' , DC = 4, 7x50 B, Dilli. (HI)
Nov. 22.24: m1 = 9.5 (+/-0.2) Dia. 4.0', DC = 5, 42x256 L, Dilli. (HI)
Nov. 23.29: m1 = 9.4 (+/-0.2) Dia. 4.0', DC = 5, 42x256 L, Dilli. (HI)
Dec. 06.25: m1 = 9.9 (+/-0.2) Dia. 4.5', DC = 4, 42x256 L, Dilli. (HI)
Dec. 11.24: m1 = 9.9 (+/-0.1) Dia. 4.5', DC = 5, 42x256 L, Dilli. (HI)
Dec. 14.24: m1 = 10.2 (+/-0.1) Dia. 4.0', DC = 5, 42x256 L, Dilli. (HI)
Dec. 17.26: m1 = 10.1 (+/-0.2) Dia. 4.0', DC = 5, 42x256 L, Dilli. (HI)
Dec. 19.23: m1 = 10.3 (+/-0.2) Dia. 4.0', DC = 4, 42x256 L, Dilli. (HI)
Dec. 20.25: m1 = 10.0 (+/-0.2) Dia. 4.0', DC = 4, 42x256 L, Dilli. (HI)
1999:
Jan. 12.26: m1 = 10.8 (+/-0.2) Dia. 2.7', DC = 5, 42x256 L, Dilli. (HI)
Jan. 14.28: m1 = 10.9 (+/-0.2) Dia. 3.0', DC = 5, 42x256 L, Dilli. (HI)
Jan. 16.27: m1 = 11.2 (+/-0.1) Dia. 2.5', DC = 5, 42x256 L, Dilli. (HI)
Jan. 17.28: m1 = 11.0 (+/-0.2) Dia. 2.5', DC = 5, 42x256 L, Dilli. (HI)
Jan. 20.30: m1 = 11.2 (+/-0.1) Dia. 2.0', DC = 4, 42x256 L, Dilli. (HI)
Feb. 13.26: m1 = 11.9 (+/-0.2) Dia. 2.0', DC = 4, 42x256 L, Dilli. (HI)
Feb. 14.25: m1 = 11.6 (+/-0.1) Dia. 1.5', DC = 4, 42x256 L, Dilli. (HI)
Feb. 16.31: m1 = 11.7 (+/-0.2) Dia. 1.5', DC = 3, 42x256 L, Dilli. (HI)
Mar. 07.25: m1 = 12.5 (+/-0.1) Dia. 1.3', DC = 3, 84x256 L, Dilli. (HI)
Mar. 09.25: m1 = 12.6 (+/-0.1) Dia. 1.3', DC = 5, 84x256 L, Dilli. (HI)
Mar. 12.26: m1 = 12.5 (+/-0.2) Dia. 1.1', DC = 4, 84x256 L, Dilli. (HI)
Mar. 14.26: m1 = 12.8 (+/-0.2) Dia. 1.0', DC = 3, 84x256 L, Dilli. (HI)
Mar. 17.28: m1 = 13.1 (+/-0.2) Dia. 0.8', DC = 5, 84x256 L, Dilli. (HI)
Mar. 23.27: m1 = 13.0 (+/-0.2) Dia. 0.8', DC = 4, 169x256 L, Dilli. (HI)
Apr. 05.25: m1 = 13.1 (+/-0.2) Dia. 1.0', DC = 3, 84x256 L, Dilli. (HI)
Apr. 08.25: m1 = 13.4 (+/-0.2) Dia. 1.0', DC = 3, 84x256 L, Dilli. (HI)
Comments:
June 30.5: Under good circumstances (high elevation, no wind, good seeing, N.E. limit = 6.3+) I may have seen the comet: no faint stars could have been superimposed to what I saw, according to DSS. 15.2 mag stars were seen nearby. Extremely difficult observation, of course...

July 25-26: Under good circumstances the comet is clearly visible, small and rather condensed but faint, motion obviously noticed on July 25.33->25.43.
Sep. 11.28: 2.5' tail in PA 90°, m2 = 14.3 (+/-0.3) (169x256 L)
Sep. 13.28: 2.5' tail in PA 80°, m2 = 14.8 (+/-0.3) (169x256 L)
Sep. 15.29: 2.0' tail in PA 85°, m2 = 14.6 (+/-0.3) (169x256 L)
Oct. 09.26: 5.0' tail in PA 80° (169x256 L)
Oct. 18.28: 6' tail in PA 80°, m2 = 14.4 (+/-0.3) (169x256 L)
Oct. 20.27: 7' tail in PA 70°, m2 = 13.5 (+/-0.3) (169x256 L)
Oct. 23.24: 9' tail in PA 70°
Oct. 24.28: 12' tail in PA 70°
Nov. 07.24: 12' tail in PA 65°, m2 = 13.9 (+/-0.2) (507x256 L)
Nov. 17.28: 12' tail in PA 70°
Nov. 21.24: 15' tail in PA 70°, m2 = 13.9 (+/-0.2) (169x256 L)
Nov. 22.25: 12' tail in PA 70°, m2 = 13.8 (+/-0.2) (169x256 L)
Nov. 23.26: 16' tail in PA 70°, m2 = 13.2 (+/-0.3) (169x256 L)
Dec. 06.25: 10' tail in PA (340->)70°, m2 = 13.7 (+/-0.2) (169x256 L)
Dec. 11.24: 10' tail in PA 65°, m2 = 14.3 (+/-0.2) (169x256 L)
Dec. 19.24: 8' tail in PA 55°, m2 = 14.1 (+/-0.2) (169x256 L)
Dec. 20.26: 10' tail in PA 55°, m2 = 14.0 (+/-0.2) (169x256 L)
Jan. 12.26: 4' tail in PA 55°
Jan. 14.28: 4' tail in PA 50°

Images:

[25 K] Sep. 11.5: Drawing at 169x (25.6cm L) 8'x8' South is up

[42 K] Nov. 23.3: Drawing at 169x (25.6cm L) 10'x10' South is up

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2005:
May 06.12: m1 = 11.4 (+/-0.2) Dia. 2.0', DC = 5, 67x203ScT,PicoVeleta(Sp)
May 07.10: m1 = 11.1 (+/-0.2) Dia. 2.4', DC = 5, 67x203ScT,PicoVeleta(Sp)
May 12.10: m1 = 11.6:(+/-0.2) Dia. 1.5', DC = 5, 116x407 L, Poigny-G.(Fr)
June
July 2.17: m1 = 10.3 (+/-0.2) Dia. 2.5', DC = 5, 67x203ScT,PicoVeleta(Sp)
Comments:
May 06.13: 4' tail in PA 260°, m2 = 14.1 (+/-0.2) (160x203ScT)
May 07.11: 4' tail in PA 260°, m2 = 13.8 (+/-0.1) (160x203ScT)
May 12.11: m2 = 13.7 (+/-0.2) (233x407 L)
July 07.17: 6' tail in PA 275°, m2 = 13.1 (+/-0.2) (160x203ScT)

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