メタデータ
| 項目 |
値 |
| Designation |
C/2014 S2 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2015-12-09T19:08:29.909760Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:00Z |
| Obs used |
2941 |
| NEO |
- |
| M1 |
6.000 |
| K1 |
13.250 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2016-01-10.0000000 |
| e |
0.98762625 |
| q (au) |
2.100643 |
| a (au) |
169.766118 |
| i (deg) |
64.670381 |
| Ω (om, deg) |
8.122248 |
| ω (w, deg) |
87.806610 |
| M (ma, deg) |
0.013903 |
等級
散乱 + 全体線形
$$
M_a = (5.333 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
5.333 |
| n |
6.000 |
| gf |
0.802 |
| gb |
-0.500 |
| k |
0.936 |
| 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
残差 (区間線形)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| 開始日 (UTC) |
終了日 (UTC) |
a |
b |
| 2014-04-28 |
2015-04-25 |
-24.2188 |
+17.742 |
| 2015-04-25 |
2015-12-09 |
+33.0276 |
-11.675 |
| 2015-12-09 |
2017-04-01 |
+2.8013 |
-2.446 |
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) |
| 2026-05-12 00:00 |
12:32:47.53 |
-58:50:16.5 |
HIP 61312 |
17.78 |
| 2026-05-12 12:00 |
12:32:41.08 |
-58:49:29.7 |
HIP 61312 |
18.82 |
| 2026-05-13 00:00 |
12:32:34.70 |
-58:48:42.7 |
HIP 61312 |
19.88 |
| 2026-05-13 12:00 |
12:32:28.36 |
-58:47:55.3 |
HIP 61312 |
20.94 |
| 2026-05-14 00:00 |
12:32:22.09 |
-58:47:07.7 |
HIP 61312 |
22.01 |
| 2026-05-14 12:00 |
12:32:15.87 |
-58:46:19.8 |
HIP 60949 |
22.66 |
| 2026-05-15 00:00 |
12:32:09.72 |
-58:45:31.6 |
HIP 60949 |
21.60 |
| 2026-05-15 12:00 |
12:32:03.62 |
-58:44:43.2 |
HIP 60949 |
20.55 |
| 2026-05-16 00:00 |
12:31:57.58 |
-58:43:54.5 |
HIP 60949 |
19.52 |
| 2026-05-16 12:00 |
12:31:51.60 |
-58:43:05.5 |
HIP 60949 |
18.50 |
| 2026-05-17 00:00 |
12:31:45.69 |
-58:42:16.3 |
HIP 60949 |
17.50 |
| 2026-05-17 12:00 |
12:31:39.83 |
-58:41:26.8 |
HIP 60949 |
16.52 |
| 2026-05-18 00:00 |
12:31:34.03 |
-58:40:37.1 |
HIP 60949 |
15.57 |
| 2026-05-18 12:00 |
12:31:28.30 |
-58:39:47.1 |
HIP 60949 |
14.64 |
| 2026-05-19 00:00 |
12:31:22.63 |
-58:38:56.9 |
HIP 60949 |
13.76 |
| 2026-05-19 12:00 |
12:31:17.02 |
-58:38:06.5 |
HIP 60949 |
12.91 |
| 2026-05-20 00:00 |
12:31:11.47 |
-58:37:15.9 |
HIP 60949 |
12.12 |
| 2026-05-20 12:00 |
12:31:05.99 |
-58:36:25.0 |
HIP 60949 |
11.38 |
| 2026-05-21 00:00 |
12:31:00.57 |
-58:35:34.0 |
HIP 60949 |
10.72 |
| 2026-05-21 12:00 |
12:30:55.22 |
-58:34:42.7 |
HIP 60949 |
10.15 |
| 2026-05-22 00:00 |
12:30:49.92 |
-58:33:51.2 |
HIP 60949 |
9.68 |
| 2026-05-22 12:00 |
12:30:44.70 |
-58:32:59.5 |
HIP 60949 |
9.32 |
| 2026-05-23 00:00 |
12:30:39.54 |
-58:32:07.7 |
HIP 60949 |
9.09 |
| 2026-05-23 12:00 |
12:30:34.44 |
-58:31:15.6 |
HIP 60949 |
8.99 |
| 2026-05-24 00:00 |
12:30:29.41 |
-58:30:23.4 |
HIP 60949 |
9.04 |
| 2026-05-24 12:00 |
12:30:24.44 |
-58:29:31.0 |
HIP 60949 |
9.22 |
| 2026-05-25 00:00 |
12:30:19.54 |
-58:28:38.4 |
HIP 60949 |
9.53 |
| 2026-05-25 12:00 |
12:30:14.70 |
-58:27:45.7 |
HIP 60949 |
9.96 |
| 2026-05-26 00:00 |
12:30:09.93 |
-58:26:52.8 |
HIP 60949 |
10.49 |
| 2026-05-26 12:00 |
12:30:05.23 |
-58:25:59.8 |
HIP 60949 |
11.10 |
| 2026-05-27 00:00 |
12:30:00.60 |
-58:25:06.6 |
HIP 60949 |
11.78 |
| 2026-05-27 12:00 |
12:29:56.03 |
-58:24:13.2 |
HIP 60949 |
12.52 |
| 2026-05-28 00:00 |
12:29:51.52 |
-58:23:19.8 |
HIP 60949 |
13.31 |
| 2026-05-28 12:00 |
12:29:47.09 |
-58:22:26.1 |
HIP 61049 |
13.61 |
| 2026-05-29 00:00 |
12:29:42.72 |
-58:21:32.4 |
HIP 61049 |
13.24 |
| 2026-05-29 12:00 |
12:29:38.42 |
-58:20:38.5 |
HIP 60884 |
12.36 |
| 2026-05-30 00:00 |
12:29:34.19 |
-58:19:44.5 |
HIP 60884 |
11.31 |
| 2026-05-30 12:00 |
12:29:30.02 |
-58:18:50.4 |
HIP 60884 |
10.27 |
| 2026-05-31 00:00 |
12:29:25.92 |
-58:17:56.2 |
HIP 60884 |
9.23 |
| 2026-05-31 12:00 |
12:29:21.89 |
-58:17:01.9 |
HIP 60884 |
8.21 |
| 2026-06-01 00:00 |
12:29:17.93 |
-58:16:07.4 |
HIP 60884 |
7.19 |
| 2026-06-01 12:00 |
12:29:14.04 |
-58:15:12.9 |
HIP 60884 |
6.19 |
| 2026-06-02 00:00 |
12:29:10.22 |
-58:14:18.3 |
HIP 60884 |
5.21 |