Comet Archive

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C/2018 M1 (Catalina)

メタデータ

項目
Designation C/2018 M1 (Catalina)
Type C
Perihelion (tp_cal, UTC) 2018-07-10T00:35:11.529600Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:33:44Z
Obs used 171
NEO -
M1 16.600
K1 5.250
PC 0.030
Discovery observation (MPC, UTC) 2018-06-25T10:26:00.672000Z
Discovery magnitude (MPC) 17.60 G
Discovery observatory (MPC) 703 · Catalina Sky Survey
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 2018-08-16.0000000
e 0.93870003
q (au) 1.303480
a (au) 21.263951
i (deg) 37.257024
Ω (om, deg) 339.463309
ω (w, deg) 14.132786
M (ma, deg) 0.371666

等級

C/2018 M1 (Catalina) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (16.433 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 16.433
n 2.000
gf 0.800
gb -0.500
k 0.965
δ90 1.000
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 10:28:33.55 +16:00:19.4 HIP 51279 15.07
2026-02-03 12:00 10:28:27.58 +16:00:51.4 HIP 51279 15.51
2026-02-04 00:00 10:28:21.59 +16:01:23.4 HIP 51279 16.08
2026-02-04 12:00 10:28:15.58 +16:01:55.4 HIP 51279 16.78
2026-02-05 00:00 10:28:09.54 +16:02:27.5 HIP 51279 17.59
2026-02-05 12:00 10:28:03.49 +16:02:59.5 HIP 51201 18.42
2026-02-06 00:00 10:27:57.41 +16:03:31.6 HIP 51221 17.88
2026-02-06 12:00 10:27:51.32 +16:04:03.7 HIP 51221 17.13
2026-02-07 00:00 10:27:45.20 +16:04:35.7 HIP 51221 16.50
2026-02-07 12:00 10:27:39.07 +16:05:07.8 HIP 51221 16.00
2026-02-08 00:00 10:27:32.92 +16:05:39.8 HIP 51221 15.64
2026-02-08 12:00 10:27:26.75 +16:06:11.8 HIP 51221 15.43
2026-02-09 00:00 10:27:20.57 +16:06:43.8 HIP 51221 15.38
2026-02-09 12:00 10:27:14.37 +16:07:15.8 HIP 51221 15.50
2026-02-10 00:00 10:27:08.15 +16:07:47.8 HIP 51221 15.77
2026-02-10 12:00 10:27:01.92 +16:08:19.7 HIP 51221 16.20
2026-02-11 00:00 10:26:55.68 +16:08:51.6 HIP 51221 16.77
2026-02-11 12:00 10:26:49.42 +16:09:23.4 HIP 51221 17.48
2026-02-12 00:00 10:26:43.15 +16:09:55.3 HIP 51221 18.29
2026-02-12 12:00 10:26:36.86 +16:10:27.0 HIP 51221 19.21
2026-02-13 00:00 10:26:30.56 +16:10:58.8 HIP 51221 20.22
2026-02-13 12:00 10:26:24.26 +16:11:30.4 HIP 51221 21.30
2026-02-14 00:00 10:26:17.94 +16:12:02.1 HIP 51221 22.44
2026-02-14 12:00 10:26:11.61 +16:12:33.6 HIP 51221 23.65
2026-02-15 00:00 10:26:05.27 +16:13:05.1 HIP 51221 24.90
2026-02-15 12:00 10:25:58.92 +16:13:36.6 HIP 51221 26.19
2026-02-16 00:00 10:25:52.56 +16:14:08.0 HIP 51221 27.52
2026-02-16 12:00 10:25:46.20 +16:14:39.3 HIP 51221 28.88
2026-02-17 00:00 10:25:39.83 +16:15:10.5 HIP 51221 30.26
2026-02-17 12:00 10:25:33.45 +16:15:41.6 HIP 51221 31.67
2026-02-18 00:00 10:25:27.07 +16:16:12.7 HIP 51221 33.10
2026-02-18 12:00 10:25:20.68 +16:16:43.7 HIP 51221 34.55
2026-02-19 00:00 10:25:14.29 +16:17:14.6 HIP 51221 36.01
2026-02-19 12:00 10:25:07.89 +16:17:45.3 HIP 51221 37.48
2026-02-20 00:00 10:25:01.49 +16:18:16.0 HIP 51020 37.32
2026-02-20 12:00 10:24:55.09 +16:18:46.6 HIP 51020 37.06
2026-02-21 00:00 10:24:48.68 +16:19:17.1 HIP 51020 36.88
2026-02-21 12:00 10:24:42.28 +16:19:47.5 HIP 51020 36.76
2026-02-22 00:00 10:24:35.87 +16:20:17.8 HIP 50784 35.84
2026-02-22 12:00 10:24:29.47 +16:20:47.9 HIP 50784 34.23
2026-02-23 00:00 10:24:23.06 +16:21:17.9 HIP 50784 32.62
2026-02-23 12:00 10:24:16.66 +16:21:47.9 HIP 50784 31.02
2026-02-24 00:00 10:24:10.25 +16:22:17.6 HIP 50784 29.41