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208P/McMillan

메타데이터

항목
Designation 208P/McMillan
Type P
Perihelion (tp_cal, UTC) 2016-07-02T01:58:31.463040Z
Orbit solution date (soln_date, UTC) 2025-10-28T16:12:51Z
Obs used 402
NEO -
M1 16.100
K1 4.500
PC -
Osculating 궤도요소
항목
Epoch (epoch_cal, TDB) 2014-08-19.0000000
e 0.37204667
q (au) 2.543028
a (au) 4.049708
i (deg) 4.409401
Ω (om, deg) 36.427937
ω (w, deg) 310.603963
M (ma, deg) 277.388305

밝기

208P/McMillan · Magnitude (Full range)

산란 + 전체 선형

$$ M_a = (14.986 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

모델 상수

항목
H0 14.986
n 2.000
gf 1.000
gb -0.533
k 1.000
δ90 10.000
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

찾아보기

208P/McMillan · Next 30 Days

천체력

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-02-03 00:00 05:30:39.09 +27:50:58.4 HIP 25871 10.79
2026-02-03 12:00 05:30:33.05 +27:50:33.3 HIP 25871 11.84
2026-02-04 00:00 05:30:27.33 +27:50:08.3 HIP 25871 12.89
2026-02-04 12:00 05:30:21.91 +27:49:43.4 HIP 25871 13.92
2026-02-05 00:00 05:30:16.79 +27:49:18.5 HIP 25871 14.92
2026-02-05 12:00 05:30:11.98 +27:48:53.6 HIP 25871 15.89
2026-02-06 00:00 05:30:07.48 +27:48:28.9 HIP 25871 16.81
2026-02-06 12:00 05:30:03.29 +27:48:04.2 HIP 25871 17.68
2026-02-07 00:00 05:29:59.40 +27:47:39.6 HIP 25871 18.49
2026-02-07 12:00 05:29:55.82 +27:47:15.1 HIP 25871 19.26
2026-02-08 00:00 05:29:52.55 +27:46:50.7 HIP 25871 19.96
2026-02-08 12:00 05:29:49.58 +27:46:26.5 HIP 25871 20.61
2026-02-09 00:00 05:29:46.91 +27:46:02.3 HIP 25871 21.20
2026-02-09 12:00 05:29:44.55 +27:45:38.2 HIP 25871 21.73
2026-02-10 00:00 05:29:42.49 +27:45:14.3 HIP 25871 22.19
2026-02-10 12:00 05:29:40.74 +27:44:50.5 HIP 25871 22.60
2026-02-11 00:00 05:29:39.29 +27:44:26.8 HIP 25871 22.95
2026-02-11 12:00 05:29:38.15 +27:44:03.2 HIP 25871 23.23
2026-02-12 00:00 05:29:37.30 +27:43:39.8 HIP 25871 23.46
2026-02-12 12:00 05:29:36.76 +27:43:16.6 HIP 25871 23.62
2026-02-13 00:00 05:29:36.52 +27:42:53.4 HIP 25871 23.73
2026-02-13 12:00 05:29:36.58 +27:42:30.4 HIP 25871 23.77
2026-02-14 00:00 05:29:36.94 +27:42:07.6 HIP 25871 23.75
2026-02-14 12:00 05:29:37.61 +27:41:45.0 HIP 25871 23.68
2026-02-15 00:00 05:29:38.56 +27:41:22.4 HIP 25871 23.54
2026-02-15 12:00 05:29:39.82 +27:41:00.1 HIP 25871 23.35
2026-02-16 00:00 05:29:41.37 +27:40:37.9 HIP 25871 23.10
2026-02-16 12:00 05:29:43.22 +27:40:15.9 HIP 25871 22.79
2026-02-17 00:00 05:29:45.37 +27:39:54.1 HIP 25871 22.44
2026-02-17 12:00 05:29:47.81 +27:39:32.4 HIP 25871 22.02
2026-02-18 00:00 05:29:50.54 +27:39:10.9 HIP 25871 21.56
2026-02-18 12:00 05:29:53.57 +27:38:49.5 HIP 25871 21.05
2026-02-19 00:00 05:29:56.88 +27:38:28.4 HIP 25871 20.49
2026-02-19 12:00 05:30:00.49 +27:38:07.4 HIP 25871 19.89
2026-02-20 00:00 05:30:04.39 +27:37:46.6 HIP 25871 19.26
2026-02-20 12:00 05:30:08.57 +27:37:26.0 HIP 25871 18.59
2026-02-21 00:00 05:30:13.04 +27:37:05.6 HIP 25871 17.89
2026-02-21 12:00 05:30:17.79 +27:36:45.3 HIP 25871 17.17
2026-02-22 00:00 05:30:22.83 +27:36:25.2 HIP 25871 16.45
2026-02-22 12:00 05:30:28.15 +27:36:05.3 HIP 25871 15.72
2026-02-23 00:00 05:30:33.75 +27:35:45.6 HIP 25871 15.02
2026-02-23 12:00 05:30:39.63 +27:35:26.1 HIP 25871 14.35
2026-02-24 00:00 05:30:45.79 +27:35:06.8 HIP 25871 13.74