Comet Archive

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C/1991 R1 (McNaught-Russell)

メタデータ

項目
Designation C/1991 R1 (McNaught-Russell)
Type C
Perihelion (tp_cal, UTC) 1990-11-10T22:00:23.633280Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:29:41Z
Obs used 41
NEO -
M1 4.400
K1 11.000
PC -
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 1993-05-02.0000000
e 0.99985167
q (au) 6.981918
a (au) 47069.984909
i (deg) 104.522092
Ω (om, deg) 150.114710
ω (w, deg) 149.130210
M (ma, deg) 0.000087

等級

C/1991 R1 (McNaught-Russell) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (4.641 + 4.023\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 4.641
n 4.023
gf 0.982
gb -0.998
k 1.000
δ90 9.986
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 09:21:26.07 -61:44:33.2 HIP 45733 14.47
2026-02-03 12:00 09:21:21.69 -61:44:31.1 HIP 45733 13.95
2026-02-04 00:00 09:21:17.30 -61:44:28.7 HIP 45733 13.43
2026-02-04 12:00 09:21:12.91 -61:44:26.0 HIP 45733 12.91
2026-02-05 00:00 09:21:08.51 -61:44:23.0 HIP 45733 12.39
2026-02-05 12:00 09:21:04.12 -61:44:19.7 HIP 45733 11.87
2026-02-06 00:00 09:20:59.72 -61:44:16.1 HIP 45733 11.35
2026-02-06 12:00 09:20:55.33 -61:44:12.3 HIP 45733 10.83
2026-02-07 00:00 09:20:50.93 -61:44:08.1 HIP 45733 10.31
2026-02-07 12:00 09:20:46.53 -61:44:03.7 HIP 45733 9.79
2026-02-08 00:00 09:20:42.14 -61:43:58.9 HIP 45733 9.27
2026-02-08 12:00 09:20:37.74 -61:43:53.9 HIP 45733 8.75
2026-02-09 00:00 09:20:33.35 -61:43:48.6 HIP 45733 8.24
2026-02-09 12:00 09:20:28.96 -61:43:43.0 HIP 45733 7.72
2026-02-10 00:00 09:20:24.57 -61:43:37.0 HIP 45733 7.21
2026-02-10 12:00 09:20:20.18 -61:43:30.8 HIP 45733 6.70
2026-02-11 00:00 09:20:15.79 -61:43:24.4 HIP 45733 6.20
2026-02-11 12:00 09:20:11.41 -61:43:17.6 HIP 45733 5.71
2026-02-12 00:00 09:20:07.03 -61:43:10.5 HIP 45733 5.22
2026-02-12 12:00 09:20:02.66 -61:43:03.2 HIP 45733 4.74
2026-02-13 00:00 09:19:58.28 -61:42:55.5 HIP 45733 4.28
2026-02-13 12:00 09:19:53.92 -61:42:47.6 HIP 45733 3.84
2026-02-14 00:00 09:19:49.56 -61:42:39.3 HIP 45733 3.43
2026-02-14 12:00 09:19:45.20 -61:42:30.8 HIP 45733 3.06
2026-02-15 00:00 09:19:40.85 -61:42:22.0 HIP 45733 2.75
2026-02-15 12:00 09:19:36.51 -61:42:12.9 HIP 45733 2.52
2026-02-16 00:00 09:19:32.17 -61:42:03.6 HIP 45733 2.39
2026-02-16 12:00 09:19:27.84 -61:41:53.9 HIP 45733 2.39
2026-02-17 00:00 09:19:23.52 -61:41:44.0 HIP 45733 2.51
2026-02-17 12:00 09:19:19.20 -61:41:33.7 HIP 45733 2.73
2026-02-18 00:00 09:19:14.90 -61:41:23.2 HIP 45733 3.04
2026-02-18 12:00 09:19:10.60 -61:41:12.4 HIP 45733 3.42
2026-02-19 00:00 09:19:06.31 -61:41:01.3 HIP 45733 3.83
2026-02-19 12:00 09:19:02.03 -61:40:50.0 HIP 45733 4.28
2026-02-20 00:00 09:18:57.76 -61:40:38.3 HIP 45733 4.75
2026-02-20 12:00 09:18:53.50 -61:40:26.4 HIP 45639 5.21
2026-02-21 00:00 09:18:49.25 -61:40:14.2 HIP 45639 4.72
2026-02-21 12:00 09:18:45.01 -61:40:01.8 HIP 45639 4.25
2026-02-22 00:00 09:18:40.79 -61:39:49.0 HIP 45639 3.81
2026-02-22 12:00 09:18:36.57 -61:39:36.0 HIP 45639 3.39
2026-02-23 00:00 09:18:32.37 -61:39:22.7 HIP 45639 3.02
2026-02-23 12:00 09:18:28.18 -61:39:09.1 HIP 45639 2.71
2026-02-24 00:00 09:18:24.00 -61:38:55.3 HIP 45639 2.49