Comet Archive

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C/1999 S2 (McNaught-Watson)

메타데이터

항목
Designation C/1999 S2 (McNaught-Watson)
Type C
Perihelion (tp_cal, UTC) 1997-11-22T14:49:59.252160Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:30:02Z
Obs used 88
NEO -
M1 8.000
K1 4.500
PC -
Osculating 궤도요소
항목
Epoch (epoch_cal, TDB) 2000-03-17.0000000
e 1.00527083
q (au) 6.467743
a (au) -1227.083165
i (deg) 65.820220
Ω (om, deg) 74.460976
ω (w, deg) 223.497414
M (ma, deg) 0.019384

밝기

C/1999 S2 (McNaught-Watson) · Magnitude (Full range)

산란 + 전체 선형

$$ M_a = (12.223 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

모델 상수

항목
H0 12.223
n 2.000
gf 0.828
gb -0.827
k 0.800
δ90 9.796
파라미터 기호 범위 설명
태양·지구거리 1 AU에서의 절대등급 H0 -5 to 20 혜성의 고유 밝기
광도 기울기 파라미터 n 2 to 6 태양거리 변화에 따른 밝기 변화율
전방 산란 비대칭 계수 gf 0.8 to 1 전방 산란의 강도
후방 산란 비대칭 계수 gb -1 to -0.5 후방 산란의 강도
분할 계수 k 0.8 to 1 전·후방 산란 기여도 비율
먼지/가스 밝기 비 δ90 1 to 10 코마에서 먼지 산란 대비 가스 방출의 상대 기여

참고: EPSC-DPS2025-160

천체력

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-02-03 00:00 04:47:07.12 +21:55:48.4 HIP 22291 19.21
2026-02-03 12:00 04:47:05.82 +21:55:49.2 HIP 22291 19.41
2026-02-04 00:00 04:47:04.54 +21:55:49.9 HIP 22291 19.60
2026-02-04 12:00 04:47:03.28 +21:55:50.7 HIP 22291 19.79
2026-02-05 00:00 04:47:02.04 +21:55:51.6 HIP 22291 19.98
2026-02-05 12:00 04:47:00.83 +21:55:52.4 HIP 22291 20.16
2026-02-06 00:00 04:46:59.63 +21:55:53.3 HIP 22291 20.35
2026-02-06 12:00 04:46:58.46 +21:55:54.3 HIP 22291 20.53
2026-02-07 00:00 04:46:57.31 +21:55:55.3 HIP 22291 20.71
2026-02-07 12:00 04:46:56.19 +21:55:56.3 HIP 22291 20.89
2026-02-08 00:00 04:46:55.08 +21:55:57.4 HIP 22291 21.07
2026-02-08 12:00 04:46:54.00 +21:55:58.5 HIP 22291 21.24
2026-02-09 00:00 04:46:52.94 +21:55:59.6 HIP 22291 21.41
2026-02-09 12:00 04:46:51.90 +21:56:00.8 HIP 22291 21.58
2026-02-10 00:00 04:46:50.89 +21:56:02.0 HIP 22291 21.74
2026-02-10 12:00 04:46:49.90 +21:56:03.3 HIP 22291 21.90
2026-02-11 00:00 04:46:48.93 +21:56:04.6 HIP 22291 22.06
2026-02-11 12:00 04:46:47.98 +21:56:05.9 HIP 22291 22.21
2026-02-12 00:00 04:46:47.06 +21:56:07.3 HIP 22291 22.37
2026-02-12 12:00 04:46:46.16 +21:56:08.7 HIP 22291 22.51
2026-02-13 00:00 04:46:45.28 +21:56:10.2 HIP 22291 22.66
2026-02-13 12:00 04:46:44.43 +21:56:11.7 HIP 22291 22.80
2026-02-14 00:00 04:46:43.60 +21:56:13.2 HIP 22291 22.93
2026-02-14 12:00 04:46:42.79 +21:56:14.8 HIP 22291 23.07
2026-02-15 00:00 04:46:42.01 +21:56:16.4 HIP 22291 23.19
2026-02-15 12:00 04:46:41.25 +21:56:18.1 HIP 22291 23.32
2026-02-16 00:00 04:46:40.51 +21:56:19.8 HIP 22291 23.44
2026-02-16 12:00 04:46:39.80 +21:56:21.5 HIP 22291 23.56
2026-02-17 00:00 04:46:39.11 +21:56:23.3 HIP 22291 23.67
2026-02-17 12:00 04:46:38.45 +21:56:25.2 HIP 22291 23.78
2026-02-18 00:00 04:46:37.80 +21:56:27.0 HIP 22291 23.88
2026-02-18 12:00 04:46:37.18 +21:56:28.9 HIP 22291 23.98
2026-02-19 00:00 04:46:36.59 +21:56:30.9 HIP 22291 24.07
2026-02-19 12:00 04:46:36.02 +21:56:32.9 HIP 22222 24.15
2026-02-20 00:00 04:46:35.47 +21:56:34.9 HIP 22222 24.13
2026-02-20 12:00 04:46:34.95 +21:56:37.0 HIP 22222 24.11
2026-02-21 00:00 04:46:34.45 +21:56:39.1 HIP 22222 24.08
2026-02-21 12:00 04:46:33.97 +21:56:41.2 HIP 22222 24.06
2026-02-22 00:00 04:46:33.52 +21:56:43.4 HIP 22222 24.04
2026-02-22 12:00 04:46:33.09 +21:56:45.6 HIP 22222 24.01
2026-02-23 00:00 04:46:32.69 +21:56:47.9 HIP 22222 23.99
2026-02-23 12:00 04:46:32.31 +21:56:50.2 HIP 22222 23.96
2026-02-24 00:00 04:46:31.95 +21:56:52.6 HIP 22222 23.93