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

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

モデル定数

項目
H0 14.986
n 2.000
gf 1.000
gb -0.533
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)
2026-05-12 00:00 06:26:05.07 +26:52:29.9 HIP 30724 20.48
2026-05-12 12:00 06:26:36.42 +26:52:01.4 HIP 30724 15.11
2026-05-13 00:00 06:27:07.85 +26:51:32.6 HIP 30724 11.63
2026-05-13 12:00 06:27:39.33 +26:51:03.4 HIP 30724 11.88
2026-05-14 00:00 06:28:10.89 +26:50:34.0 HIP 30880 12.60
2026-05-14 12:00 06:28:42.51 +26:50:04.2 HIP 30880 8.56
2026-05-15 00:00 06:29:14.19 +26:49:34.1 HIP 30880 9.38
2026-05-15 12:00 06:29:45.93 +26:49:03.7 HIP 30984 9.51
2026-05-16 00:00 06:30:17.73 +26:48:32.9 HIP 30984 8.63
2026-05-16 12:00 06:30:49.60 +26:48:01.8 HIP 30984 12.64
2026-05-17 00:00 06:31:21.52 +26:47:30.4 HIP 30984 18.63
2026-05-17 12:00 06:31:53.50 +26:46:58.6 HIP 31213 12.89
2026-05-18 00:00 06:32:25.54 +26:46:26.5 HIP 31213 5.74
2026-05-18 12:00 06:32:57.63 +26:45:54.1 HIP 31213 1.62
2026-05-19 00:00 06:33:29.78 +26:45:21.3 HIP 31213 8.70
2026-05-19 12:00 06:34:01.98 +26:44:48.2 HIP 31213 15.90
2026-05-20 00:00 06:34:34.23 +26:44:14.7 HIP 31310 20.14
2026-05-20 12:00 06:35:06.54 +26:43:40.9 HIP 31535 13.31
2026-05-21 00:00 06:35:38.89 +26:43:06.8 HIP 31535 6.07
2026-05-21 12:00 06:36:11.30 +26:42:32.3 HIP 31535 1.22
2026-05-22 00:00 06:36:43.75 +26:41:57.5 HIP 31535 8.47
2026-05-22 12:00 06:37:16.25 +26:41:22.3 HIP 31545 14.95
2026-05-23 00:00 06:37:48.80 +26:40:46.8 HIP 31774 15.71
2026-05-23 12:00 06:38:21.39 +26:40:10.9 HIP 31774 10.99
2026-05-24 00:00 06:38:54.03 +26:39:34.7 HIP 31774 10.09
2026-05-24 12:00 06:39:26.71 +26:38:58.2 HIP 31774 13.79
2026-05-25 00:00 06:39:59.43 +26:38:21.2 HIP 31774 19.65
2026-05-25 12:00 06:40:32.20 +26:37:44.0 HIP 31774 26.28
2026-05-26 00:00 06:41:05.00 +26:37:06.3 HIP 32057 21.51
2026-05-26 12:00 06:41:37.85 +26:36:28.4 HIP 32057 18.31
2026-05-27 00:00 06:42:10.73 +26:35:50.0 HIP 32057 17.80
2026-05-27 12:00 06:42:43.66 +26:35:11.3 HIP 32057 20.18
2026-05-28 00:00 06:43:16.62 +26:34:32.3 HIP 32232 21.80
2026-05-28 12:00 06:43:49.62 +26:33:52.9 HIP 32232 20.38
2026-05-29 00:00 06:44:22.66 +26:33:13.2 HIP 32232 21.57
2026-05-29 12:00 06:44:55.73 +26:32:33.0 HIP 32306 24.90
2026-05-30 00:00 06:45:28.84 +26:31:52.6 HIP 32518 22.87
2026-05-30 12:00 06:46:01.98 +26:31:11.7 HIP 32518 15.58
2026-05-31 00:00 06:46:35.15 +26:30:30.5 HIP 32518 8.57
2026-05-31 12:00 06:47:08.36 +26:29:49.0 HIP 32518 3.90
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