メタデータ
| 項目 |
値 |
| Designation |
305P/Skiff |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2014-11-14T20:47:51.241920Z |
| Orbit solution date (soln_date, UTC) |
2025-03-12T14:12:24Z |
| Obs used |
1263 |
| NEO |
- |
| M1 |
17.000 |
| K1 |
6.750 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2019-06-23.0000000 |
| e |
0.69233211 |
| q (au) |
1.429531 |
| a (au) |
4.646345 |
| i (deg) |
11.636720 |
| Ω (om, deg) |
240.147035 |
| ω (w, deg) |
147.273501 |
| M (ma, deg) |
165.439476 |
等級
散乱 + 全体線形
$$
M_a = (15.192 + 5.556\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
15.192 |
| n |
5.556 |
| 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
残差 (区間線形)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| 開始日 (UTC) |
終了日 (UTC) |
a |
b |
| 2024-08-05 |
2025-02-16 |
-9.7820 |
+1.600 |
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) |
| 2026-03-26 00:00 |
10:02:59.69 |
-03:12:58.0 |
HIP 49287 |
18.61 |
| 2026-03-26 12:00 |
10:02:46.65 |
-03:10:30.0 |
HIP 49287 |
22.46 |
| 2026-03-27 00:00 |
10:02:33.82 |
-03:08:02.5 |
HIP 49126 |
19.77 |
| 2026-03-27 12:00 |
10:02:21.19 |
-03:05:35.5 |
HIP 49126 |
15.80 |
| 2026-03-28 00:00 |
10:02:08.77 |
-03:03:09.1 |
HIP 49126 |
11.89 |
| 2026-03-28 12:00 |
10:01:56.56 |
-03:00:43.3 |
HIP 49126 |
8.05 |
| 2026-03-29 00:00 |
10:01:44.55 |
-02:58:18.0 |
HIP 49126 |
4.36 |
| 2026-03-29 12:00 |
10:01:32.75 |
-02:55:53.3 |
HIP 49126 |
1.70 |
| 2026-03-30 00:00 |
10:01:21.16 |
-02:53:29.3 |
HIP 49126 |
3.91 |
| 2026-03-30 12:00 |
10:01:09.78 |
-02:51:05.9 |
HIP 49126 |
7.43 |
| 2026-03-31 00:00 |
10:00:58.61 |
-02:48:43.1 |
HIP 49126 |
11.02 |
| 2026-03-31 12:00 |
10:00:47.65 |
-02:46:21.0 |
HIP 49126 |
14.60 |
| 2026-04-01 00:00 |
10:00:36.90 |
-02:43:59.6 |
HIP 49126 |
18.15 |
| 2026-04-01 12:00 |
10:00:26.37 |
-02:41:38.9 |
HIP 49126 |
21.66 |
| 2026-04-02 00:00 |
10:00:16.05 |
-02:39:18.9 |
HIP 49126 |
25.12 |
| 2026-04-02 12:00 |
10:00:05.94 |
-02:36:59.7 |
HIP 49126 |
28.53 |
| 2026-04-03 00:00 |
09:59:56.05 |
-02:34:41.2 |
HIP 48935 |
29.85 |
| 2026-04-03 12:00 |
09:59:46.37 |
-02:32:23.4 |
HIP 48935 |
30.97 |
| 2026-04-04 00:00 |
09:59:36.91 |
-02:30:06.4 |
HIP 48935 |
32.39 |
| 2026-04-04 12:00 |
09:59:27.67 |
-02:27:50.3 |
HIP 48935 |
34.07 |
| 2026-04-05 00:00 |
09:59:18.64 |
-02:25:34.9 |
HIP 48935 |
35.96 |
| 2026-04-05 12:00 |
09:59:09.82 |
-02:23:20.4 |
HIP 48847 |
33.38 |
| 2026-04-06 00:00 |
09:59:01.23 |
-02:21:06.6 |
HIP 48847 |
30.31 |
| 2026-04-06 12:00 |
09:58:52.85 |
-02:18:53.8 |
HIP 48847 |
27.28 |
| 2026-04-07 00:00 |
09:58:44.69 |
-02:16:41.8 |
HIP 48847 |
24.31 |
| 2026-04-07 12:00 |
09:58:36.75 |
-02:14:30.7 |
HIP 48847 |
21.38 |
| 2026-04-08 00:00 |
09:58:29.02 |
-02:12:20.4 |
HIP 48847 |
18.50 |
| 2026-04-08 12:00 |
09:58:21.52 |
-02:10:11.1 |
HIP 48847 |
15.68 |
| 2026-04-09 00:00 |
09:58:14.23 |
-02:08:02.7 |
HIP 48847 |
12.91 |
| 2026-04-09 12:00 |
09:58:07.16 |
-02:05:55.2 |
HIP 48847 |
10.20 |
| 2026-04-10 00:00 |
09:58:00.31 |
-02:03:48.6 |
HIP 48847 |
7.57 |
| 2026-04-10 12:00 |
09:57:53.68 |
-02:01:43.0 |
HIP 48847 |
5.05 |
| 2026-04-11 00:00 |
09:57:47.27 |
-01:59:38.4 |
HIP 48847 |
2.83 |
| 2026-04-11 12:00 |
09:57:41.08 |
-01:57:34.7 |
HIP 48839 |
1.28 |
| 2026-04-12 00:00 |
09:57:35.11 |
-01:55:32.0 |
HIP 48839 |
2.40 |
| 2026-04-12 12:00 |
09:57:29.36 |
-01:53:30.3 |
HIP 48839 |
4.71 |
| 2026-04-13 00:00 |
09:57:23.83 |
-01:51:29.7 |
HIP 48839 |
7.09 |
| 2026-04-13 12:00 |
09:57:18.51 |
-01:49:30.0 |
HIP 48839 |
9.45 |
| 2026-04-14 00:00 |
09:57:13.42 |
-01:47:31.4 |
HIP 48839 |
11.78 |
| 2026-04-14 12:00 |
09:57:08.55 |
-01:45:33.8 |
HIP 48839 |
14.06 |
| 2026-04-15 00:00 |
09:57:03.89 |
-01:43:37.3 |
HIP 48839 |
16.31 |
| 2026-04-15 12:00 |
09:56:59.46 |
-01:41:41.8 |
HIP 48839 |
18.51 |
| 2026-04-16 00:00 |
09:56:55.24 |
-01:39:47.5 |
HIP 48839 |
20.67 |