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)
2026-07-29 00:00 15:39:51.30 +01:27:53.4 HIP 76751 7.54
2026-07-29 12:00 15:39:49.34 +01:27:08.5 HIP 76751 8.09
2026-07-30 00:00 15:39:47.44 +01:26:23.2 HIP 76751 8.68
2026-07-30 12:00 15:39:45.60 +01:25:37.7 HIP 76751 9.30
2026-07-31 00:00 15:39:43.82 +01:24:52.0 HIP 76751 9.96
2026-07-31 12:00 15:39:42.11 +01:24:06.0 HIP 76751 10.63
2026-08-01 00:00 15:39:40.46 +01:23:19.7 HIP 76751 11.32
2026-08-01 12:00 15:39:38.88 +01:22:33.1 HIP 76751 12.02
2026-08-02 00:00 15:39:37.36 +01:21:46.3 HIP 76751 12.73
2026-08-02 12:00 15:39:35.90 +01:20:59.3 HIP 76751 13.45
2026-08-03 00:00 15:39:34.50 +01:20:12.0 HIP 76751 14.17
2026-08-03 12:00 15:39:33.17 +01:19:24.4 HIP 76751 14.90
2026-08-04 00:00 15:39:31.90 +01:18:36.6 HIP 76751 15.63
2026-08-04 12:00 15:39:30.70 +01:17:48.6 HIP 76751 16.36
2026-08-05 00:00 15:39:29.56 +01:17:00.3 HIP 76751 17.09
2026-08-05 12:00 15:39:28.48 +01:16:11.7 HIP 76751 17.83
2026-08-06 00:00 15:39:27.47 +01:15:23.0 HIP 76751 18.57
2026-08-06 12:00 15:39:26.52 +01:14:34.0 HIP 76751 19.31
2026-08-07 00:00 15:39:25.64 +01:13:44.7 HIP 76751 20.05
2026-08-07 12:00 15:39:24.82 +01:12:55.3 HIP 76751 20.78
2026-08-08 00:00 15:39:24.06 +01:12:05.6 HIP 76751 21.52
2026-08-08 12:00 15:39:23.37 +01:11:15.7 HIP 76577 21.86
2026-08-09 00:00 15:39:22.74 +01:10:25.6 HIP 76577 21.19
2026-08-09 12:00 15:39:22.18 +01:09:35.2 HIP 76577 20.53
2026-08-10 00:00 15:39:21.68 +01:08:44.7 HIP 76577 19.91
2026-08-10 12:00 15:39:21.25 +01:07:53.9 HIP 76577 19.31
2026-08-11 00:00 15:39:20.88 +01:07:02.9 HIP 76577 18.74
2026-08-11 12:00 15:39:20.57 +01:06:11.8 HIP 76577 18.20
2026-08-12 00:00 15:39:20.33 +01:05:20.4 HIP 76577 17.70
2026-08-12 12:00 15:39:20.15 +01:04:28.8 HIP 76577 17.25
2026-08-13 00:00 15:39:20.04 +01:03:37.0 HIP 76577 16.84
2026-08-13 12:00 15:39:19.99 +01:02:45.1 HIP 76577 16.47
2026-08-14 00:00 15:39:20.01 +01:01:52.9 HIP 76577 16.16
2026-08-14 12:00 15:39:20.09 +01:01:00.6 HIP 76577 15.91
2026-08-15 00:00 15:39:20.23 +01:00:08.1 HIP 76577 15.71
2026-08-15 12:00 15:39:20.44 +00:59:15.4 HIP 76577 15.58
2026-08-16 00:00 15:39:20.71 +00:58:22.5 HIP 76577 15.51
2026-08-16 12:00 15:39:21.05 +00:57:29.5 HIP 76577 15.51
2026-08-17 00:00 15:39:21.45 +00:56:36.3 HIP 76577 15.57
2026-08-17 12:00 15:39:21.91 +00:55:42.9 HIP 76577 15.70
2026-08-18 00:00 15:39:22.44 +00:54:49.4 HIP 76577 15.90
2026-08-18 12:00 15:39:23.03 +00:53:55.7 HIP 76577 16.16
2026-08-19 00:00 15:39:23.69 +00:53:01.9 HIP 76577 16.48