メタデータ
| 項目 |
値 |
| Designation |
195P/Hill |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2025-07-30T07:20:09.395520Z |
| Orbit solution date (soln_date, UTC) |
2026-05-08T13:42:12Z |
| Obs used |
1221 |
| NEO |
- |
| M1 |
6.900 |
| K1 |
12.500 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2020-01-01.0000000 |
| e |
0.31339822 |
| q (au) |
4.460369 |
| a (au) |
6.496297 |
| i (deg) |
36.342162 |
| Ω (om, deg) |
243.092944 |
| ω (w, deg) |
249.537667 |
| M (ma, deg) |
238.727735 |
等級
散乱 + 全体線形
$$
M_a = (4.207 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
4.207 |
| n |
6.000 |
| gf |
0.992 |
| gb |
-0.500 |
| k |
1.000 |
| δ90 |
9.999 |
| 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 |
| 2021-09-13 |
2022-11-27 |
-11.3967 |
+9.275 |
| 2022-11-27 |
2023-10-30 |
-4.2313 |
+3.570 |
| 2023-10-30 |
2025-05-13 |
+7.0564 |
-4.823 |
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 |
09:27:47.61 |
-25:32:25.2 |
HIP 46469 |
13.21 |
| 2026-05-12 12:00 |
09:28:02.72 |
-25:29:26.3 |
HIP 46469 |
8.83 |
| 2026-05-13 00:00 |
09:28:18.01 |
-25:26:28.6 |
HIP 46469 |
4.71 |
| 2026-05-13 12:00 |
09:28:33.49 |
-25:23:32.2 |
HIP 46469 |
2.75 |
| 2026-05-14 00:00 |
09:28:49.15 |
-25:20:37.1 |
HIP 46469 |
5.88 |
| 2026-05-14 12:00 |
09:29:04.99 |
-25:17:43.4 |
HIP 46469 |
10.19 |
| 2026-05-15 00:00 |
09:29:21.01 |
-25:14:50.9 |
HIP 46469 |
14.69 |
| 2026-05-15 12:00 |
09:29:37.22 |
-25:11:59.9 |
HIP 46469 |
19.26 |
| 2026-05-16 00:00 |
09:29:53.60 |
-25:09:10.1 |
HIP 46685 |
15.74 |
| 2026-05-16 12:00 |
09:30:10.15 |
-25:06:21.8 |
HIP 46685 |
11.85 |
| 2026-05-17 00:00 |
09:30:26.89 |
-25:03:34.8 |
HIP 46685 |
8.71 |
| 2026-05-17 12:00 |
09:30:43.79 |
-25:00:49.2 |
HIP 46685 |
7.41 |
| 2026-05-18 00:00 |
09:31:00.88 |
-24:58:05.1 |
HIP 46691 |
7.78 |
| 2026-05-18 12:00 |
09:31:18.13 |
-24:55:22.3 |
HIP 46691 |
5.63 |
| 2026-05-19 00:00 |
09:31:35.55 |
-24:52:40.9 |
HIP 46691 |
7.00 |
| 2026-05-19 12:00 |
09:31:53.15 |
-24:50:01.0 |
HIP 46691 |
10.62 |
| 2026-05-20 00:00 |
09:32:10.91 |
-24:47:22.5 |
HIP 46691 |
14.95 |
| 2026-05-20 12:00 |
09:32:28.84 |
-24:44:45.5 |
HIP 46691 |
19.55 |
| 2026-05-21 00:00 |
09:32:46.94 |
-24:42:09.9 |
HIP 46691 |
24.27 |
| 2026-05-21 12:00 |
09:33:05.20 |
-24:39:35.7 |
HIP 46975 |
20.17 |
| 2026-05-22 00:00 |
09:33:23.62 |
-24:37:03.0 |
HIP 46975 |
15.37 |
| 2026-05-22 12:00 |
09:33:42.20 |
-24:34:31.8 |
HIP 46975 |
10.62 |
| 2026-05-23 00:00 |
09:34:00.95 |
-24:32:02.1 |
HIP 46975 |
6.10 |
| 2026-05-23 12:00 |
09:34:19.85 |
-24:29:33.8 |
HIP 46975 |
3.18 |
| 2026-05-24 00:00 |
09:34:38.91 |
-24:27:07.1 |
HIP 46975 |
5.68 |
| 2026-05-24 12:00 |
09:34:58.13 |
-24:24:41.8 |
HIP 46975 |
10.20 |
| 2026-05-25 00:00 |
09:35:17.50 |
-24:22:18.0 |
HIP 47002 |
12.92 |
| 2026-05-25 12:00 |
09:35:37.03 |
-24:19:55.7 |
HIP 47154 |
13.77 |
| 2026-05-26 00:00 |
09:35:56.71 |
-24:17:34.9 |
HIP 47154 |
8.72 |
| 2026-05-26 12:00 |
09:36:16.54 |
-24:15:15.6 |
HIP 47154 |
3.64 |
| 2026-05-27 00:00 |
09:36:36.52 |
-24:12:57.8 |
HIP 47154 |
1.48 |
| 2026-05-27 12:00 |
09:36:56.65 |
-24:10:41.5 |
HIP 47154 |
6.59 |
| 2026-05-28 00:00 |
09:37:16.92 |
-24:08:26.8 |
HIP 47154 |
11.73 |
| 2026-05-28 12:00 |
09:37:37.35 |
-24:06:13.5 |
HIP 47154 |
16.89 |
| 2026-05-29 00:00 |
09:37:57.91 |
-24:04:01.8 |
HIP 47365 |
15.22 |
| 2026-05-29 12:00 |
09:38:18.62 |
-24:01:51.6 |
HIP 47365 |
10.14 |
| 2026-05-30 00:00 |
09:38:39.48 |
-23:59:42.9 |
HIP 47365 |
5.28 |
| 2026-05-30 12:00 |
09:39:00.47 |
-23:57:35.7 |
HIP 47365 |
2.68 |
| 2026-05-31 00:00 |
09:39:21.61 |
-23:55:30.1 |
HIP 47365 |
6.45 |
| 2026-05-31 12:00 |
09:39:42.89 |
-23:53:26.0 |
HIP 47365 |
11.47 |
| 2026-06-01 00:00 |
09:40:04.30 |
-23:51:23.4 |
HIP 47365 |
16.67 |
| 2026-06-01 12:00 |
09:40:25.85 |
-23:49:22.4 |
HIP 47522 |
18.16 |
| 2026-06-02 00:00 |
09:40:47.54 |
-23:47:22.9 |
HIP 47522 |
13.67 |