C/2015 K2 (PANSTARRS)

メタデータ

項目
Designation C/2015 K2 (PANSTARRS)
Type C
Perihelion (tp_cal, UTC) 2015-06-08T19:07:06.248640Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:33:11Z
Obs used 54
NEO -
M1 20.700
K1 10.000
PC -
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 2015-05-26.0000000
e 0.99444359
q (au) 1.455282
a (au) 261.910605
i (deg) 29.110346
Ω (om, deg) 223.713883
ω (w, deg) 15.770089
M (ma, deg) 359.996792

等級

C/2015 K2 (PANSTARRS) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (20.000 + 3.100\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 20.000
n 3.100
gf 1.000
gb -0.500
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)
2026-06-01 00:00 02:05:38.56 +18:09:33.9 HIP 9824 22.66
2026-06-01 12:00 02:05:42.29 +18:09:54.5 HIP 9824 21.91
2026-06-02 00:00 02:05:45.99 +18:10:15.0 HIP 9824 21.19
2026-06-02 12:00 02:05:49.68 +18:10:35.4 HIP 9824 20.48
2026-06-03 00:00 02:05:53.34 +18:10:55.8 HIP 9824 19.80
2026-06-03 12:00 02:05:56.99 +18:11:16.1 HIP 9824 19.14
2026-06-04 00:00 02:06:00.61 +18:11:36.3 HIP 9824 18.51
2026-06-04 12:00 02:06:04.21 +18:11:56.5 HIP 9824 17.90
2026-06-05 00:00 02:06:07.79 +18:12:16.5 HIP 9824 17.33
2026-06-05 12:00 02:06:11.34 +18:12:36.5 HIP 9824 16.79
2026-06-06 00:00 02:06:14.87 +18:12:56.4 HIP 9824 16.28
2026-06-06 12:00 02:06:18.38 +18:13:16.2 HIP 9824 15.81
2026-06-07 00:00 02:06:21.87 +18:13:36.0 HIP 9824 15.38
2026-06-07 12:00 02:06:25.33 +18:13:55.6 HIP 9824 14.99
2026-06-08 00:00 02:06:28.77 +18:14:15.2 HIP 9824 14.65
2026-06-08 12:00 02:06:32.19 +18:14:34.7 HIP 9824 14.36
2026-06-09 00:00 02:06:35.58 +18:14:54.1 HIP 9824 14.11
2026-06-09 12:00 02:06:38.95 +18:15:13.4 HIP 9824 13.91
2026-06-10 00:00 02:06:42.30 +18:15:32.6 HIP 9824 13.77
2026-06-10 12:00 02:06:45.62 +18:15:51.7 HIP 9824 13.67
2026-06-11 00:00 02:06:48.91 +18:16:10.8 HIP 9824 13.63
2026-06-11 12:00 02:06:52.18 +18:16:29.7 HIP 9824 13.64
2026-06-12 00:00 02:06:55.43 +18:16:48.5 HIP 9824 13.70
2026-06-12 12:00 02:06:58.65 +18:17:07.3 HIP 9824 13.81
2026-06-13 00:00 02:07:01.84 +18:17:25.9 HIP 9824 13.96
2026-06-13 12:00 02:07:05.01 +18:17:44.5 HIP 9824 14.16
2026-06-14 00:00 02:07:08.15 +18:18:02.9 HIP 9824 14.39
2026-06-14 12:00 02:07:11.27 +18:18:21.2 HIP 9824 14.67
2026-06-15 00:00 02:07:14.36 +18:18:39.5 HIP 9824 14.98
2026-06-15 12:00 02:07:17.42 +18:18:57.6 HIP 9824 15.32
2026-06-16 00:00 02:07:20.46 +18:19:15.6 HIP 9824 15.68
2026-06-16 12:00 02:07:23.47 +18:19:33.5 HIP 9824 16.08
2026-06-17 00:00 02:07:26.45 +18:19:51.3 HIP 9824 16.49
2026-06-17 12:00 02:07:29.40 +18:20:09.0 HIP 9824 16.93
2026-06-18 00:00 02:07:32.33 +18:20:26.6 HIP 9824 17.38
2026-06-18 12:00 02:07:35.22 +18:20:44.1 HIP 9824 17.85
2026-06-19 00:00 02:07:38.09 +18:21:01.4 HIP 9824 18.33
2026-06-19 12:00 02:07:40.93 +18:21:18.7 HIP 9824 18.82
2026-06-20 00:00 02:07:43.75 +18:21:35.8 HIP 9824 19.33
2026-06-20 12:00 02:07:46.53 +18:21:52.8 HIP 9824 19.84
2026-06-21 00:00 02:07:49.29 +18:22:09.7 HIP 9824 20.35
2026-06-21 12:00 02:07:52.01 +18:22:26.5 HIP 9924 20.73
2026-06-22 00:00 02:07:54.71 +18:22:43.1 HIP 9924 21.06