C/2020 K4 (PANSTARRS)

メタデータ

項目 値
Designation C/2020 K4 (PANSTARRS)
Type C
Perihelion (tp_cal, UTC) 2020-03-06T12:03:58.541760Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:34:07Z
Obs used 48
NEO -
M1 17.900
K1 6.250
PC -
Discovery observation (MPC, UTC) 2020-05-20T12:49:01.488000Z
Discovery magnitude (MPC) 19.78 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 値
Epoch (epoch_cal, TDB) 2020-06-16.0000000
e 0.96121938
q (au) 1.772742
a (au) 45.712051
i (deg) 125.914307
Ω (om, deg) 264.105134
ω (w, deg) 310.291834
M (ma, deg) 0.323677

等級

C/2020 K4 (PANSTARRS) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (17.090 + 2.376\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目 値
H0 17.090
n 2.376
gf 1.000
gb -0.502
k 1.000
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)
2026-09-20 00:00 12:57:34.10 +51:14:55.9 HIP 63164 14.11
2026-09-20 12:00 12:57:42.46 +51:14:17.3 HIP 63164 14.62
2026-09-21 00:00 12:57:50.84 +51:13:39.3 HIP 63164 15.27
2026-09-21 12:00 12:57:59.24 +51:13:01.9 HIP 63164 16.04
2026-09-22 00:00 12:58:07.66 +51:12:25.1 HIP 63164 16.90
2026-09-22 12:00 12:58:16.10 +51:11:48.9 HIP 63164 17.85
2026-09-23 00:00 12:58:24.56 +51:11:13.3 HIP 63164 18.87
2026-09-23 12:00 12:58:33.04 +51:10:38.4 HIP 63164 19.95
2026-09-24 00:00 12:58:41.54 +51:10:04.0 HIP 63164 21.08
2026-09-24 12:00 12:58:50.05 +51:09:30.2 HIP 63164 22.25
2026-09-25 00:00 12:58:58.58 +51:08:57.1 HIP 63498 22.18
2026-09-25 12:00 12:59:07.13 +51:08:24.5 HIP 63498 21.65
2026-09-26 00:00 12:59:15.69 +51:07:52.6 HIP 63498 21.18
2026-09-26 12:00 12:59:24.27 +51:07:21.3 HIP 63498 20.80
2026-09-27 00:00 12:59:32.86 +51:06:50.6 HIP 63498 20.51
2026-09-27 12:00 12:59:41.47 +51:06:20.5 HIP 63498 20.30
2026-09-28 00:00 12:59:50.09 +51:05:51.1 HIP 63498 20.17
2026-09-28 12:00 12:59:58.72 +51:05:22.3 HIP 63498 20.15
2026-09-29 00:00 13:00:07.37 +51:04:54.1 HIP 63498 20.21
2026-09-29 12:00 13:00:16.03 +51:04:26.5 HIP 63498 20.36
2026-09-30 00:00 13:00:24.70 +51:03:59.6 HIP 63498 20.60
2026-09-30 12:00 13:00:33.39 +51:03:33.3 HIP 63498 20.92
2026-10-01 00:00 13:00:42.08 +51:03:07.7 HIP 63666 20.76
2026-10-01 12:00 13:00:50.79 +51:02:42.7 HIP 63666 19.38
2026-10-02 00:00 13:00:59.50 +51:02:18.4 HIP 63666 18.01
2026-10-02 12:00 13:01:08.23 +51:01:54.7 HIP 63666 16.64
2026-10-03 00:00 13:01:16.96 +51:01:31.6 HIP 63666 15.29
2026-10-03 12:00 13:01:25.70 +51:01:09.2 HIP 63666 13.94
2026-10-04 00:00 13:01:34.45 +51:00:47.4 HIP 63666 12.61
2026-10-04 12:00 13:01:43.21 +51:00:26.3 HIP 63666 11.30
2026-10-05 00:00 13:01:51.97 +51:00:05.9 HIP 63666 10.02
2026-10-05 12:00 13:02:00.74 +50:59:46.2 HIP 63666 8.77
2026-10-06 00:00 13:02:09.52 +50:59:27.0 HIP 63666 7.58
2026-10-06 12:00 13:02:18.30 +50:59:08.6 HIP 63666 6.47
2026-10-07 00:00 13:02:27.09 +50:58:50.9 HIP 63666 5.50
2026-10-07 12:00 13:02:35.87 +50:58:33.8 HIP 63666 4.74
2026-10-08 00:00 13:02:44.67 +50:58:17.3 HIP 63666 4.32
2026-10-08 12:00 13:02:53.46 +50:58:01.6 HIP 63666 4.32
2026-10-09 00:00 13:03:02.26 +50:57:46.6 HIP 63666 4.75
2026-10-09 12:00 13:03:11.06 +50:57:32.2 HIP 63666 5.51
2026-10-10 00:00 13:03:19.86 +50:57:18.5 HIP 63666 6.47
2026-10-10 12:00 13:03:28.66 +50:57:05.5 HIP 63666 7.57
2026-10-11 00:00 13:03:37.46 +50:56:53.2 HIP 63666 8.75