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)
2026-03-26 00:00 04:46:53.35 +22:00:26.4 HIP 22291 18.67
2026-03-26 12:00 04:46:54.39 +22:00:31.1 HIP 22291 18.43
2026-03-27 00:00 04:46:55.46 +22:00:35.9 HIP 22291 18.17
2026-03-27 12:00 04:46:56.54 +22:00:40.7 HIP 22291 17.92
2026-03-28 00:00 04:46:57.65 +22:00:45.5 HIP 22291 17.66
2026-03-28 12:00 04:46:58.77 +22:00:50.3 HIP 22291 17.40
2026-03-29 00:00 04:46:59.92 +22:00:55.2 HIP 22291 17.13
2026-03-29 12:00 04:47:01.09 +22:01:00.1 HIP 22291 16.86
2026-03-30 00:00 04:47:02.28 +22:01:05.1 HIP 22291 16.58
2026-03-30 12:00 04:47:03.49 +22:01:10.0 HIP 22291 16.30
2026-03-31 00:00 04:47:04.72 +22:01:15.0 HIP 22291 16.02
2026-03-31 12:00 04:47:05.97 +22:01:20.1 HIP 22291 15.73
2026-04-01 00:00 04:47:07.23 +22:01:25.2 HIP 22291 15.44
2026-04-01 12:00 04:47:08.52 +22:01:30.3 HIP 22291 15.15
2026-04-02 00:00 04:47:09.83 +22:01:35.4 HIP 22291 14.85
2026-04-02 12:00 04:47:11.16 +22:01:40.6 HIP 22291 14.55
2026-04-03 00:00 04:47:12.51 +22:01:45.8 HIP 22291 14.25
2026-04-03 12:00 04:47:13.87 +22:01:51.0 HIP 22291 13.94
2026-04-04 00:00 04:47:15.26 +22:01:56.3 HIP 22291 13.63
2026-04-04 12:00 04:47:16.67 +22:02:01.6 HIP 22291 13.32
2026-04-05 00:00 04:47:18.09 +22:02:06.9 HIP 22291 13.00
2026-04-05 12:00 04:47:19.53 +22:02:12.2 HIP 22291 12.69
2026-04-06 00:00 04:47:21.00 +22:02:17.6 HIP 22291 12.37
2026-04-06 12:00 04:47:22.48 +22:02:23.0 HIP 22291 12.05
2026-04-07 00:00 04:47:23.98 +22:02:28.5 HIP 22291 11.73
2026-04-07 12:00 04:47:25.50 +22:02:34.0 HIP 22291 11.40
2026-04-08 00:00 04:47:27.03 +22:02:39.5 HIP 22291 11.08
2026-04-08 12:00 04:47:28.59 +22:02:45.0 HIP 22291 10.75
2026-04-09 00:00 04:47:30.16 +22:02:50.6 HIP 22291 10.43
2026-04-09 12:00 04:47:31.75 +22:02:56.1 HIP 22291 10.10
2026-04-10 00:00 04:47:33.36 +22:03:01.8 HIP 22291 9.78
2026-04-10 12:00 04:47:34.99 +22:03:07.4 HIP 22291 9.45
2026-04-11 00:00 04:47:36.64 +22:03:13.1 HIP 22291 9.13
2026-04-11 12:00 04:47:38.30 +22:03:18.8 HIP 22291 8.81
2026-04-12 00:00 04:47:39.98 +22:03:24.5 HIP 22291 8.50
2026-04-12 12:00 04:47:41.68 +22:03:30.3 HIP 22291 8.19
2026-04-13 00:00 04:47:43.40 +22:03:36.0 HIP 22291 7.89
2026-04-13 12:00 04:47:45.13 +22:03:41.9 HIP 22291 7.59
2026-04-14 00:00 04:47:46.88 +22:03:47.7 HIP 22291 7.30
2026-04-14 12:00 04:47:48.65 +22:03:53.5 HIP 22291 7.03
2026-04-15 00:00 04:47:50.43 +22:03:59.4 HIP 22291 6.77
2026-04-15 12:00 04:47:52.23 +22:04:05.3 HIP 22291 6.52
2026-04-16 00:00 04:47:54.05 +22:04:11.3 HIP 22291 6.29