208P/McMillan

メタデータ

項目
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 -
オスキュレーティング軌道要素
項目
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

等級

208P/McMillan · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (14.985 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 14.985
n 2.000
gf 1.000
gb -0.565
k 1.000
δ90 10.000
パラメータ 記号 範囲 説明
太陽・地球距離が1 AUのときの絶対等級 H0 -5 to 20 彗星の固有の明るさ
測光スロープパラメータ n 2 to 6 太陽距離に対する明るさ変化率
前方散乱非対称係数 gf 0.8 to 1 前方散乱の強さ
後方散乱非対称係数 gb -1 to -0.5 後方散乱の強さ
分配係数 k 0.8 to 1 前方/後方散乱の寄与比
ダスト/ガス明るさ比 δ90 1 to 10 ダスト散乱とガス放射の相対寄与

参考: EPSC-DPS2025-160

ファインディングチャート

208P/McMillan · Next 30 Days

天体暦

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-06-01 00:00 06:47:41.60 +26:29:07.1 HIP 32518 8.27
2026-06-01 12:00 06:48:14.87 +26:28:24.8 HIP 32663 13.01
2026-06-02 00:00 06:48:48.17 +26:27:42.1 HIP 32663 9.90
2026-06-02 12:00 06:49:21.50 +26:26:59.1 HIP 32663 11.80
2026-06-03 00:00 06:49:54.86 +26:26:15.8 HIP 32663 17.12
2026-06-03 12:00 06:50:28.25 +26:25:32.0 HIP 32959 19.12
2026-06-04 00:00 06:51:01.67 +26:24:47.9 HIP 32959 11.60
2026-06-04 12:00 06:51:35.11 +26:24:03.5 HIP 32959 4.09
2026-06-05 00:00 06:52:08.59 +26:23:18.6 HIP 32959 3.48
2026-06-05 12:00 06:52:42.08 +26:22:33.4 HIP 32959 11.01
2026-06-06 00:00 06:53:15.61 +26:21:47.9 HIP 32959 18.55
2026-06-06 12:00 06:53:49.16 +26:21:01.9 HIP 33194 14.04
2026-06-07 00:00 06:54:22.73 +26:20:15.6 HIP 33194 11.67
2026-06-07 12:00 06:54:56.32 +26:19:29.0 HIP 33194 13.78
2026-06-08 00:00 06:55:29.94 +26:18:41.9 HIP 33194 18.92
2026-06-08 12:00 06:56:03.58 +26:17:54.5 HIP 33356 20.51
2026-06-09 00:00 06:56:37.24 +26:17:06.8 HIP 33356 20.10
2026-06-09 12:00 06:57:10.93 +26:16:18.6 HIP 33506 20.18
2026-06-10 00:00 06:57:44.63 +26:15:30.1 HIP 33595 17.68
2026-06-10 12:00 06:58:18.35 +26:14:41.2 HIP 33595 11.81
2026-06-11 00:00 06:58:52.10 +26:13:52.0 HIP 33595 9.07
2026-06-11 12:00 06:59:25.85 +26:13:02.4 HIP 33595 11.88
2026-06-12 00:00 06:59:59.63 +26:12:12.4 HIP 33793 14.01
2026-06-12 12:00 07:00:33.43 +26:11:22.0 HIP 33793 6.85
2026-06-13 00:00 07:01:07.23 +26:10:31.3 HIP 33793 3.71
2026-06-13 12:00 07:01:41.06 +26:09:40.2 HIP 33831 8.89
2026-06-14 00:00 07:02:14.90 +26:08:48.8 HIP 33831 14.47
2026-06-14 12:00 07:02:48.75 +26:07:57.0 HIP 33831 21.37
2026-06-15 00:00 07:03:22.61 +26:07:04.8 HIP 33831 28.66
2026-06-15 12:00 07:03:56.49 +26:06:12.2 HIP 33831 36.10
2026-06-16 00:00 07:04:30.38 +26:05:19.3 HIP 34061 40.94
2026-06-16 12:00 07:05:04.28 +26:04:26.1 HIP 34061 42.27
2026-06-17 00:00 07:05:38.18 +26:03:32.4 HIP 34061 44.89
2026-06-17 12:00 07:06:12.10 +26:02:38.4 HIP 34061 48.60
2026-06-18 00:00 07:06:46.02 +26:01:44.1 HIP 34567 42.15
2026-06-18 12:00 07:07:19.95 +26:00:49.4 HIP 34567 34.94
2026-06-19 00:00 07:07:53.88 +25:59:54.3 HIP 34567 27.99
2026-06-19 12:00 07:08:27.82 +25:58:58.9 HIP 34567 21.54
2026-06-20 00:00 07:09:01.76 +25:58:03.1 HIP 34567 16.19
2026-06-20 12:00 07:09:35.71 +25:57:07.0 HIP 34582 13.16
2026-06-21 00:00 07:10:09.66 +25:56:10.5 HIP 34582 13.37
2026-06-21 12:00 07:10:43.61 +25:55:13.7 HIP 34582 17.40
2026-06-22 00:00 07:11:17.57 +25:54:16.5 HIP 34861 22.68