メタデータ
| 項目 |
値 |
| Designation |
C/2017 C2 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2017-01-21T14:49:52.703040Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:30Z |
| Obs used |
97 |
| NEO |
- |
| M1 |
12.400 |
| K1 |
13.000 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2017-03-11.0000000 |
| e |
0.97530974 |
| q (au) |
2.430997 |
| a (au) |
98.459722 |
| i (deg) |
118.583896 |
| Ω (om, deg) |
249.819140 |
| ω (w, deg) |
138.775813 |
| M (ma, deg) |
0.048809 |
等級
散乱 + 全体線形
$$
M_a = (10.786 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
10.786 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.999 |
| 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) |
| 2026-03-26 00:00 |
00:11:37.50 |
-65:56:21.6 |
HIP 1084 |
11.52 |
| 2026-03-26 12:00 |
00:11:48.41 |
-65:56:15.7 |
HIP 1084 |
10.41 |
| 2026-03-27 00:00 |
00:11:59.31 |
-65:56:10.4 |
HIP 1084 |
9.30 |
| 2026-03-27 12:00 |
00:12:10.21 |
-65:56:05.7 |
HIP 1084 |
8.20 |
| 2026-03-28 00:00 |
00:12:21.10 |
-65:56:01.7 |
HIP 1084 |
7.10 |
| 2026-03-28 12:00 |
00:12:31.98 |
-65:55:58.2 |
HIP 1084 |
6.00 |
| 2026-03-29 00:00 |
00:12:42.85 |
-65:55:55.3 |
HIP 1084 |
4.91 |
| 2026-03-29 12:00 |
00:12:53.72 |
-65:55:53.0 |
HIP 1084 |
3.83 |
| 2026-03-30 00:00 |
00:13:04.58 |
-65:55:51.3 |
HIP 1084 |
2.76 |
| 2026-03-30 12:00 |
00:13:15.43 |
-65:55:50.1 |
HIP 1084 |
1.74 |
| 2026-03-31 00:00 |
00:13:26.27 |
-65:55:49.6 |
HIP 1084 |
0.94 |
| 2026-03-31 12:00 |
00:13:37.10 |
-65:55:49.7 |
HIP 1084 |
1.08 |
| 2026-04-01 00:00 |
00:13:47.92 |
-65:55:50.4 |
HIP 1084 |
1.96 |
| 2026-04-01 12:00 |
00:13:58.72 |
-65:55:51.6 |
HIP 1084 |
2.99 |
| 2026-04-02 00:00 |
00:14:09.52 |
-65:55:53.5 |
HIP 1084 |
4.06 |
| 2026-04-02 12:00 |
00:14:20.30 |
-65:55:55.9 |
HIP 1084 |
5.13 |
| 2026-04-03 00:00 |
00:14:31.07 |
-65:55:59.0 |
HIP 1084 |
6.22 |
| 2026-04-03 12:00 |
00:14:41.82 |
-65:56:02.6 |
HIP 1084 |
7.30 |
| 2026-04-04 00:00 |
00:14:52.56 |
-65:56:06.9 |
HIP 1084 |
8.39 |
| 2026-04-04 12:00 |
00:15:03.29 |
-65:56:11.7 |
HIP 1084 |
9.47 |
| 2026-04-05 00:00 |
00:15:14.00 |
-65:56:17.2 |
HIP 1084 |
10.56 |
| 2026-04-05 12:00 |
00:15:24.69 |
-65:56:23.2 |
HIP 1084 |
11.65 |
| 2026-04-06 00:00 |
00:15:35.37 |
-65:56:29.8 |
HIP 1084 |
12.73 |
| 2026-04-06 12:00 |
00:15:46.03 |
-65:56:37.0 |
HIP 1084 |
13.82 |
| 2026-04-07 00:00 |
00:15:56.67 |
-65:56:44.9 |
HIP 1084 |
14.90 |
| 2026-04-07 12:00 |
00:16:07.29 |
-65:56:53.3 |
HIP 1084 |
15.98 |
| 2026-04-08 00:00 |
00:16:17.90 |
-65:57:02.3 |
HIP 1084 |
17.07 |
| 2026-04-08 12:00 |
00:16:28.48 |
-65:57:11.9 |
HIP 1084 |
18.15 |
| 2026-04-09 00:00 |
00:16:39.04 |
-65:57:22.1 |
HIP 1396 |
18.39 |
| 2026-04-09 12:00 |
00:16:49.58 |
-65:57:32.9 |
HIP 1396 |
18.30 |
| 2026-04-10 00:00 |
00:17:00.11 |
-65:57:44.4 |
HIP 1396 |
18.29 |
| 2026-04-10 12:00 |
00:17:10.60 |
-65:57:56.4 |
HIP 1396 |
18.35 |
| 2026-04-11 00:00 |
00:17:21.08 |
-65:58:09.0 |
HIP 1396 |
18.48 |
| 2026-04-11 12:00 |
00:17:31.53 |
-65:58:22.2 |
HIP 1396 |
18.69 |
| 2026-04-12 00:00 |
00:17:41.96 |
-65:58:36.0 |
HIP 1396 |
18.97 |
| 2026-04-12 12:00 |
00:17:52.36 |
-65:58:50.4 |
HIP 1396 |
19.32 |
| 2026-04-13 00:00 |
00:18:02.74 |
-65:59:05.4 |
HIP 1396 |
19.73 |
| 2026-04-13 12:00 |
00:18:13.09 |
-65:59:21.0 |
HIP 1396 |
20.20 |
| 2026-04-14 00:00 |
00:18:23.41 |
-65:59:37.2 |
HIP 1396 |
20.73 |
| 2026-04-14 12:00 |
00:18:33.71 |
-65:59:54.0 |
HIP 1396 |
21.30 |
| 2026-04-15 00:00 |
00:18:43.98 |
-66:00:11.4 |
HIP 1396 |
21.93 |
| 2026-04-15 12:00 |
00:18:54.22 |
-66:00:29.4 |
HIP 1419 |
22.11 |
| 2026-04-16 00:00 |
00:19:04.43 |
-66:00:48.0 |
HIP 1707 |
21.69 |