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

$$ M_a = (12.224 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

모델 상수

항목
H0 12.224
n 2.000
gf 0.977
gb -0.827
k 0.800
δ90 9.955
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)
2026-07-29 00:00 04:56:05.31 +22:26:33.8 HIP 22935 8.04
2026-07-29 12:00 04:56:07.02 +22:26:38.9 HIP 22935 7.95
2026-07-30 00:00 04:56:08.71 +22:26:44.0 HIP 22935 7.88
2026-07-30 12:00 04:56:10.38 +22:26:49.0 HIP 22935 7.83
2026-07-31 00:00 04:56:12.04 +22:26:54.1 HIP 22935 7.80
2026-07-31 12:00 04:56:13.68 +22:26:59.1 HIP 22935 7.79
2026-08-01 00:00 04:56:15.30 +22:27:04.0 HIP 22935 7.80
2026-08-01 12:00 04:56:16.91 +22:27:09.0 HIP 22935 7.82
2026-08-02 00:00 04:56:18.49 +22:27:13.9 HIP 22935 7.86
2026-08-02 12:00 04:56:20.06 +22:27:18.8 HIP 22935 7.92
2026-08-03 00:00 04:56:21.61 +22:27:23.7 HIP 22935 8.00
2026-08-03 12:00 04:56:23.15 +22:27:28.5 HIP 22935 8.08
2026-08-04 00:00 04:56:24.67 +22:27:33.4 HIP 22935 8.19
2026-08-04 12:00 04:56:26.16 +22:27:38.1 HIP 22935 8.30
2026-08-05 00:00 04:56:27.65 +22:27:42.9 HIP 22935 8.43
2026-08-05 12:00 04:56:29.11 +22:27:47.6 HIP 22935 8.56
2026-08-06 00:00 04:56:30.55 +22:27:52.3 HIP 22935 8.71
2026-08-06 12:00 04:56:31.98 +22:27:57.0 HIP 22935 8.86
2026-08-07 00:00 04:56:33.38 +22:28:01.6 HIP 22935 9.02
2026-08-07 12:00 04:56:34.77 +22:28:06.3 HIP 22935 9.19
2026-08-08 00:00 04:56:36.14 +22:28:10.8 HIP 22935 9.37
2026-08-08 12:00 04:56:37.49 +22:28:15.4 HIP 22935 9.55
2026-08-09 00:00 04:56:38.83 +22:28:19.9 HIP 22935 9.73
2026-08-09 12:00 04:56:40.14 +22:28:24.4 HIP 22935 9.92
2026-08-10 00:00 04:56:41.43 +22:28:28.9 HIP 22935 10.11
2026-08-10 12:00 04:56:42.71 +22:28:33.3 HIP 22935 10.30
2026-08-11 00:00 04:56:43.96 +22:28:37.7 HIP 22935 10.49
2026-08-11 12:00 04:56:45.20 +22:28:42.1 HIP 22935 10.69
2026-08-12 00:00 04:56:46.41 +22:28:46.4 HIP 22935 10.88
2026-08-12 12:00 04:56:47.61 +22:28:50.8 HIP 22935 11.08
2026-08-13 00:00 04:56:48.78 +22:28:55.0 HIP 22935 11.28
2026-08-13 12:00 04:56:49.94 +22:28:59.3 HIP 22935 11.47
2026-08-14 00:00 04:56:51.07 +22:29:03.5 HIP 22935 11.67
2026-08-14 12:00 04:56:52.19 +22:29:07.7 HIP 22935 11.86
2026-08-15 00:00 04:56:53.28 +22:29:11.9 HIP 22935 12.06
2026-08-15 12:00 04:56:54.36 +22:29:16.0 HIP 22935 12.25
2026-08-16 00:00 04:56:55.41 +22:29:20.1 HIP 22935 12.44
2026-08-16 12:00 04:56:56.45 +22:29:24.2 HIP 22935 12.63
2026-08-17 00:00 04:56:57.46 +22:29:28.2 HIP 22935 12.81
2026-08-17 12:00 04:56:58.45 +22:29:32.2 HIP 22935 13.00
2026-08-18 00:00 04:56:59.42 +22:29:36.2 HIP 22935 13.18
2026-08-18 12:00 04:57:00.38 +22:29:40.1 HIP 22935 13.36
2026-08-19 00:00 04:57:01.31 +22:29:44.1 HIP 22935 13.53