Comet Archive

Clear skies!

C/2021 P1 (PANSTARRS)

メタデータ

項目
Designation C/2021 P1 (PANSTARRS)
Type C
Perihelion (tp_cal, UTC) 2022-06-01T16:41:49.732800Z
Orbit solution date (soln_date, UTC) 2024-03-19T12:12:38Z
Obs used 104
NEO -
M1 12.700
K1 7.000
PC -
Discovery observation (MPC, UTC) 2021-08-04T13:25:21.792000Z
Discovery magnitude (MPC) 21.20 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) 2021-09-13.0000000
e 1.00024450
q (au) 4.374954
a (au) -17893.332037
i (deg) 51.622012
Ω (om, deg) 359.671523
ω (w, deg) 40.363907
M (ma, deg) -0.000108

等級

C/2021 P1 (PANSTARRS) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (17.879 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 17.879
n 2.000
gf 0.999
gb -0.791
k 0.800
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 11:26:30.29 +39:01:34.3 HIP 55819 22.62
2026-02-03 12:00 11:26:19.85 +39:02:35.5 HIP 55819 21.61
2026-02-04 00:00 11:26:09.33 +39:03:36.2 HIP 55819 20.80
2026-02-04 12:00 11:25:58.74 +39:04:36.4 HIP 55819 20.23
2026-02-05 00:00 11:25:48.07 +39:05:36.1 HIP 55819 19.92
2026-02-05 12:00 11:25:37.32 +39:06:35.2 HIP 55819 19.88
2026-02-06 00:00 11:25:26.50 +39:07:33.9 HIP 55819 20.12
2026-02-06 12:00 11:25:15.61 +39:08:32.0 HIP 55819 20.64
2026-02-07 00:00 11:25:04.64 +39:09:29.5 HIP 55819 21.42
2026-02-07 12:00 11:24:53.60 +39:10:26.5 HIP 55819 22.42
2026-02-08 00:00 11:24:42.49 +39:11:22.9 HIP 55819 23.63
2026-02-08 12:00 11:24:31.31 +39:12:18.7 HIP 55819 25.02
2026-02-09 00:00 11:24:20.07 +39:13:13.9 HIP 55819 26.56
2026-02-09 12:00 11:24:08.75 +39:14:08.5 HIP 55819 28.23
2026-02-10 00:00 11:23:57.37 +39:15:02.5 HIP 55819 30.01
2026-02-10 12:00 11:23:45.93 +39:15:55.9 HIP 55819 31.88
2026-02-11 00:00 11:23:34.42 +39:16:48.6 HIP 55447 32.93
2026-02-11 12:00 11:23:22.86 +39:17:40.7 HIP 55447 30.65
2026-02-12 00:00 11:23:11.23 +39:18:32.2 HIP 55447 28.39
2026-02-12 12:00 11:22:59.54 +39:19:22.9 HIP 55447 26.15
2026-02-13 00:00 11:22:47.79 +39:20:13.0 HIP 55447 23.94
2026-02-13 12:00 11:22:35.99 +39:21:02.5 HIP 55447 21.78
2026-02-14 00:00 11:22:24.13 +39:21:51.2 HIP 55447 19.69
2026-02-14 12:00 11:22:12.22 +39:22:39.2 HIP 55447 17.69
2026-02-15 00:00 11:22:00.25 +39:23:26.5 HIP 55447 15.81
2026-02-15 12:00 11:21:48.24 +39:24:13.1 HIP 55447 14.12
2026-02-16 00:00 11:21:36.17 +39:24:58.9 HIP 55447 12.68
2026-02-16 12:00 11:21:24.06 +39:25:44.0 HIP 55447 11.60
2026-02-17 00:00 11:21:11.89 +39:26:28.4 HIP 55447 10.99
2026-02-17 12:00 11:20:59.69 +39:27:12.0 HIP 55447 10.92
2026-02-18 00:00 11:20:47.44 +39:27:54.8 HIP 55447 11.41
2026-02-18 12:00 11:20:35.14 +39:28:36.8 HIP 55447 12.40
2026-02-19 00:00 11:20:22.81 +39:29:18.1 HIP 55447 13.78
2026-02-19 12:00 11:20:10.43 +39:29:58.6 HIP 55447 15.45
2026-02-20 00:00 11:19:58.02 +39:30:38.2 HIP 55447 17.32
2026-02-20 12:00 11:19:45.57 +39:31:17.1 HIP 55447 19.35
2026-02-21 00:00 11:19:33.08 +39:31:55.1 HIP 55447 21.48
2026-02-21 12:00 11:19:20.56 +39:32:32.3 HIP 55447 23.68
2026-02-22 00:00 11:19:08.01 +39:33:08.7 HIP 55447 25.95
2026-02-22 12:00 11:18:55.43 +39:33:44.2 HIP 55447 28.26
2026-02-23 00:00 11:18:42.82 +39:34:18.9 HIP 55103 27.54
2026-02-23 12:00 11:18:30.18 +39:34:52.8 HIP 55103 25.35
2026-02-24 00:00 11:18:17.52 +39:35:25.7 HIP 55103 23.23