C/2015 H2 (PANSTARRS)

メタデータ

項目
Designation C/2015 H2 (PANSTARRS)
Type C
Perihelion (tp_cal, UTC) 2016-09-13T06:35:06.138240Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:33:09Z
Obs used 204
NEO -
M1 11.300
K1 5.000
PC -
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 2017-02-24.0000000
e 1.00351211
q (au) 4.967122
a (au) -1414.285460
i (deg) 33.705314
Ω (om, deg) 350.691893
ω (w, deg) 287.907632
M (ma, deg) 0.003034

等級

C/2015 H2 (PANSTARRS) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (8.727 + 2.871\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 8.727
n 2.871
gf 1.000
gb -0.966
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

残差 (区間線形)

$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$

開始日 (UTC) 終了日 (UTC) a b
2014-05-19 2016-09-08 +5.0679 -3.734
2016-11-03 2018-08-10 +6.2905 -4.906
2018-08-10 2019-10-22 -4.7741 +4.167

log10 r = log10(太陽距離/AU)、Δ = 地球距離(AU)

天体暦

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-06-01 00:00 01:42:50.19 +37:00:03.0 HIP 8072 11.62
2026-06-01 12:00 01:42:55.29 +37:00:52.8 HIP 8072 10.35
2026-06-02 00:00 01:43:00.36 +37:01:42.8 HIP 8072 9.11
2026-06-02 12:00 01:43:05.39 +37:02:32.8 HIP 8072 7.88
2026-06-03 00:00 01:43:10.40 +37:03:22.8 HIP 8072 6.70
2026-06-03 12:00 01:43:15.37 +37:04:12.9 HIP 8072 5.57
2026-06-04 00:00 01:43:20.30 +37:05:03.1 HIP 8072 4.55
2026-06-04 12:00 01:43:25.21 +37:05:53.3 HIP 8072 3.70
2026-06-05 00:00 01:43:30.07 +37:06:43.6 HIP 8072 3.17
2026-06-05 12:00 01:43:34.91 +37:07:33.9 HIP 8072 3.12
2026-06-06 00:00 01:43:39.71 +37:08:24.3 HIP 8072 3.56
2026-06-06 12:00 01:43:44.48 +37:09:14.7 HIP 8072 4.35
2026-06-07 00:00 01:43:49.21 +37:10:05.2 HIP 8072 5.32
2026-06-07 12:00 01:43:53.91 +37:10:55.7 HIP 8072 6.40
2026-06-08 00:00 01:43:58.57 +37:11:46.2 HIP 8072 7.52
2026-06-08 12:00 01:44:03.19 +37:12:36.8 HIP 8072 8.69
2026-06-09 00:00 01:44:07.78 +37:13:27.4 HIP 8072 9.86
2026-06-09 12:00 01:44:12.33 +37:14:18.1 HIP 8072 11.05
2026-06-10 00:00 01:44:16.85 +37:15:08.7 HIP 8072 12.25
2026-06-10 12:00 01:44:21.33 +37:15:59.4 HIP 8072 13.45
2026-06-11 00:00 01:44:25.77 +37:16:50.2 HIP 8072 14.65
2026-06-11 12:00 01:44:30.17 +37:17:40.9 HIP 8072 15.85
2026-06-12 00:00 01:44:34.54 +37:18:31.7 HIP 8072 17.04
2026-06-12 12:00 01:44:38.86 +37:19:22.4 HIP 8072 18.24
2026-06-13 00:00 01:44:43.15 +37:20:13.2 HIP 8072 19.43
2026-06-13 12:00 01:44:47.40 +37:21:04.0 HIP 8123 19.64
2026-06-14 00:00 01:44:51.61 +37:21:54.8 HIP 8123 19.05
2026-06-14 12:00 01:44:55.78 +37:22:45.6 HIP 8123 18.51
2026-06-15 00:00 01:44:59.92 +37:23:36.4 HIP 8123 18.03
2026-06-15 12:00 01:45:04.01 +37:24:27.3 HIP 8123 17.62
2026-06-16 00:00 01:45:08.06 +37:25:18.1 HIP 8123 17.27
2026-06-16 12:00 01:45:12.07 +37:26:08.9 HIP 8123 16.99
2026-06-17 00:00 01:45:16.04 +37:26:59.7 HIP 8123 16.78
2026-06-17 12:00 01:45:19.97 +37:27:50.4 HIP 8123 16.65
2026-06-18 00:00 01:45:23.86 +37:28:41.2 HIP 8123 16.58
2026-06-18 12:00 01:45:27.70 +37:29:32.0 HIP 8123 16.59
2026-06-19 00:00 01:45:31.51 +37:30:22.7 HIP 8123 16.67
2026-06-19 12:00 01:45:35.27 +37:31:13.4 HIP 8123 16.82
2026-06-20 00:00 01:45:38.99 +37:32:04.1 HIP 8123 17.03
2026-06-20 12:00 01:45:42.67 +37:32:54.8 HIP 8123 17.31
2026-06-21 00:00 01:45:46.30 +37:33:45.4 HIP 8123 17.65
2026-06-21 12:00 01:45:49.89 +37:34:36.0 HIP 8123 18.04
2026-06-22 00:00 01:45:53.44 +37:35:26.6 HIP 8123 18.47