Comet Archive

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389P/Siding Spring

メタデータ

項目
Designation 389P/Siding Spring
Type P
Perihelion (tp_cal, UTC) 2020-01-02T20:23:08.842560Z
Orbit solution date (soln_date, UTC) 2022-07-31T01:43:35Z
Obs used 103
NEO -
M1 14.300
K1 19.500
PC 0.030
Discovery observation (MPC, UTC) 2019-09-25T12:36:33.696000Z
Discovery magnitude (MPC) 20.50 w
Discovery observatory (MPC) F51 · Pan-STARRS 1, Haleakala
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 2013-11-08.0000000
e 0.70466929
q (au) 1.659623
a (au) 5.619542
i (deg) 160.071918
Ω (om, deg) 218.811242
ω (w, deg) 249.490302
M (ma, deg) 193.763391

等級

389P/Siding Spring · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (14.922 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 14.922
n 6.000
gf 1.000
gb -0.937
k 0.999
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

天体暦

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-02-03 00:00 11:08:26.81 +27:13:07.9 HIP 54644 34.73
2026-02-03 12:00 11:08:12.47 +27:15:11.8 HIP 54644 37.93
2026-02-04 00:00 11:07:58.04 +27:17:15.5 HIP 54644 41.25
2026-02-04 12:00 11:07:43.53 +27:19:18.9 HIP 54492 43.07
2026-02-05 00:00 11:07:28.93 +27:21:22.1 HIP 54492 42.54
2026-02-05 12:00 11:07:14.25 +27:23:25.0 HIP 54146 41.72
2026-02-06 00:00 11:06:59.50 +27:25:27.6 HIP 54146 37.86
2026-02-06 12:00 11:06:44.66 +27:27:29.9 HIP 54146 33.99
2026-02-07 00:00 11:06:29.75 +27:29:32.0 HIP 54146 30.10
2026-02-07 12:00 11:06:14.76 +27:31:33.7 HIP 54146 26.21
2026-02-08 00:00 11:05:59.70 +27:33:35.1 HIP 54146 22.31
2026-02-08 12:00 11:05:44.56 +27:35:36.1 HIP 54146 18.40
2026-02-09 00:00 11:05:29.35 +27:37:36.8 HIP 54146 14.49
2026-02-09 12:00 11:05:14.07 +27:39:37.1 HIP 54146 10.57
2026-02-10 00:00 11:04:58.72 +27:41:37.0 HIP 54146 6.66
2026-02-10 12:00 11:04:43.29 +27:43:36.6 HIP 54146 2.85
2026-02-11 00:00 11:04:27.81 +27:45:35.7 HIP 54146 1.78
2026-02-11 12:00 11:04:12.25 +27:47:34.5 HIP 54146 5.45
2026-02-12 00:00 11:03:56.63 +27:49:32.8 HIP 54146 9.38
2026-02-12 12:00 11:03:40.95 +27:51:30.6 HIP 54146 13.34
2026-02-13 00:00 11:03:25.21 +27:53:28.0 HIP 53932 16.98
2026-02-13 12:00 11:03:09.40 +27:55:25.0 HIP 53932 13.79
2026-02-14 00:00 11:02:53.54 +27:57:21.4 HIP 53932 11.12
2026-02-14 12:00 11:02:37.62 +27:59:17.4 HIP 53932 9.43
2026-02-15 00:00 11:02:21.65 +28:01:12.8 HIP 53932 9.29
2026-02-15 12:00 11:02:05.61 +28:03:07.8 HIP 53932 10.76
2026-02-16 00:00 11:01:49.53 +28:05:02.2 HIP 53932 13.32
2026-02-16 12:00 11:01:33.40 +28:06:56.1 HIP 53932 16.48
2026-02-17 00:00 11:01:17.21 +28:08:49.4 HIP 53932 19.96
2026-02-17 12:00 11:01:00.98 +28:10:42.1 HIP 53722 20.42
2026-02-18 00:00 11:00:44.70 +28:12:34.3 HIP 53722 17.33
2026-02-18 12:00 11:00:28.37 +28:14:25.9 HIP 53722 14.70
2026-02-19 00:00 11:00:12.01 +28:16:16.9 HIP 53722 12.82
2026-02-19 12:00 10:59:55.60 +28:18:07.2 HIP 53722 12.04
2026-02-20 00:00 10:59:39.15 +28:19:57.0 HIP 53722 12.58
2026-02-20 12:00 10:59:22.66 +28:21:46.1 HIP 53722 14.30
2026-02-21 00:00 10:59:06.13 +28:23:34.6 HIP 53722 16.83
2026-02-21 12:00 10:58:49.57 +28:25:22.4 HIP 53722 19.87
2026-02-22 00:00 10:58:32.98 +28:27:09.5 HIP 53722 23.22
2026-02-22 12:00 10:58:16.35 +28:28:56.0 HIP 53722 26.76
2026-02-23 00:00 10:57:59.70 +28:30:41.8 HIP 53541 27.73
2026-02-23 12:00 10:57:43.01 +28:32:26.8 HIP 53541 24.86
2026-02-24 00:00 10:57:26.30 +28:34:11.2 HIP 53541 22.37