Comet Archive

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C/2018 X3 (PANSTARRS)

メタデータ

項目
Designation C/2018 X3 (PANSTARRS)
Type C
Perihelion (tp_cal, UTC) 2018-12-30T19:11:56.958720Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:33:48Z
Obs used 50
NEO -
M1 16.900
K1 4.500
PC -
Discovery observation (MPC, UTC) 2018-12-12T11:04:53.472000Z
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) 2018-12-10.0000000
e 0.78271953
q (au) 2.698917
a (au) 12.421353
i (deg) 43.369641
Ω (om, deg) 78.924758
ω (w, deg) 359.834482
M (ma, deg) 359.531712

等級

C/2018 X3 (PANSTARRS) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (16.711 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 16.711
n 2.000
gf 0.800
gb -0.500
k 0.943
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 16:04:03.75 +00:26:16.0 HIP 78742 15.49
2026-02-03 12:00 16:04:07.08 +00:26:36.4 HIP 78742 14.85
2026-02-04 00:00 16:04:10.34 +00:26:57.1 HIP 78742 14.23
2026-02-04 12:00 16:04:13.55 +00:27:18.2 HIP 78742 13.64
2026-02-05 00:00 16:04:16.69 +00:27:39.6 HIP 78742 13.09
2026-02-05 12:00 16:04:19.77 +00:28:01.2 HIP 78742 12.57
2026-02-06 00:00 16:04:22.78 +00:28:23.2 HIP 78742 12.08
2026-02-06 12:00 16:04:25.73 +00:28:45.6 HIP 78742 11.63
2026-02-07 00:00 16:04:28.61 +00:29:08.2 HIP 78742 11.21
2026-02-07 12:00 16:04:31.43 +00:29:31.1 HIP 78742 10.84
2026-02-08 00:00 16:04:34.18 +00:29:54.4 HIP 78742 10.50
2026-02-08 12:00 16:04:36.87 +00:30:17.9 HIP 78742 10.21
2026-02-09 00:00 16:04:39.49 +00:30:41.8 HIP 78742 9.96
2026-02-09 12:00 16:04:42.05 +00:31:05.9 HIP 78742 9.76
2026-02-10 00:00 16:04:44.54 +00:31:30.4 HIP 78742 9.60
2026-02-10 12:00 16:04:46.96 +00:31:55.1 HIP 78742 9.48
2026-02-11 00:00 16:04:49.32 +00:32:20.1 HIP 78742 9.41
2026-02-11 12:00 16:04:51.61 +00:32:45.4 HIP 78742 9.37
2026-02-12 00:00 16:04:53.83 +00:33:11.1 HIP 78742 9.38
2026-02-12 12:00 16:04:55.98 +00:33:36.9 HIP 78742 9.42
2026-02-13 00:00 16:04:58.07 +00:34:03.1 HIP 78742 9.50
2026-02-13 12:00 16:05:00.09 +00:34:29.6 HIP 78742 9.61
2026-02-14 00:00 16:05:02.04 +00:34:56.3 HIP 78742 9.75
2026-02-14 12:00 16:05:03.93 +00:35:23.3 HIP 78742 9.91
2026-02-15 00:00 16:05:05.74 +00:35:50.6 HIP 78742 10.10
2026-02-15 12:00 16:05:07.49 +00:36:18.1 HIP 78742 10.30
2026-02-16 00:00 16:05:09.16 +00:36:45.9 HIP 78742 10.52
2026-02-16 12:00 16:05:10.77 +00:37:14.0 HIP 78742 10.76
2026-02-17 00:00 16:05:12.31 +00:37:42.3 HIP 78742 11.00
2026-02-17 12:00 16:05:13.78 +00:38:10.9 HIP 78742 11.26
2026-02-18 00:00 16:05:15.18 +00:38:39.7 HIP 78742 11.52
2026-02-18 12:00 16:05:16.52 +00:39:08.8 HIP 78742 11.79
2026-02-19 00:00 16:05:17.78 +00:39:38.1 HIP 78742 12.07
2026-02-19 12:00 16:05:18.97 +00:40:07.6 HIP 78742 12.35
2026-02-20 00:00 16:05:20.09 +00:40:37.4 HIP 78742 12.63
2026-02-20 12:00 16:05:21.14 +00:41:07.5 HIP 78742 12.91
2026-02-21 00:00 16:05:22.13 +00:41:37.7 HIP 78742 13.20
2026-02-21 12:00 16:05:23.04 +00:42:08.2 HIP 78742 13.48
2026-02-22 00:00 16:05:23.88 +00:42:38.9 HIP 78742 13.77
2026-02-22 12:00 16:05:24.65 +00:43:09.9 HIP 78742 14.05
2026-02-23 00:00 16:05:25.35 +00:43:41.0 HIP 78742 14.33
2026-02-23 12:00 16:05:25.99 +00:44:12.4 HIP 78742 14.62
2026-02-24 00:00 16:05:26.55 +00:44:43.9 HIP 78742 14.90