メタデータ
| 項目 |
値 |
| Designation |
C/1917 F1 (Mellish) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1917-04-11T04:12:43.113600Z |
| Orbit solution date (soln_date, UTC) |
2025-09-09T12:42:30Z |
| Obs used |
12 |
| NEO |
Yes |
| M1 |
10.900 |
| K1 |
15.750 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
1917-04-17.0000000 |
| e |
0.99302944 |
| q (au) |
0.190197 |
| a (au) |
27.285690 |
| i (deg) |
32.686283 |
| Ω (om, deg) |
88.675684 |
| ω (w, deg) |
121.313996 |
| M (ma, deg) |
0.040277 |
等級
散乱 + 全体線形
$$
M_a = (9.401 + 5.430\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
9.401 |
| n |
5.430 |
| gf |
0.800 |
| gb |
-1.000 |
| k |
1.000 |
| 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
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-06-01 00:00 |
02:58:23.11 |
-10:03:41.2 |
HIP 13883 |
18.11 |
| 2026-06-01 12:00 |
02:58:25.50 |
-10:03:38.6 |
HIP 13883 |
17.88 |
| 2026-06-02 00:00 |
02:58:27.89 |
-10:03:36.1 |
HIP 13883 |
17.67 |
| 2026-06-02 12:00 |
02:58:30.27 |
-10:03:33.8 |
HIP 13883 |
17.49 |
| 2026-06-03 00:00 |
02:58:32.64 |
-10:03:31.7 |
HIP 13883 |
17.32 |
| 2026-06-03 12:00 |
02:58:35.00 |
-10:03:29.7 |
HIP 13883 |
17.18 |
| 2026-06-04 00:00 |
02:58:37.35 |
-10:03:28.0 |
HIP 13883 |
17.06 |
| 2026-06-04 12:00 |
02:58:39.70 |
-10:03:26.4 |
HIP 13883 |
16.96 |
| 2026-06-05 00:00 |
02:58:42.03 |
-10:03:24.9 |
HIP 13883 |
16.88 |
| 2026-06-05 12:00 |
02:58:44.36 |
-10:03:23.7 |
HIP 13883 |
16.82 |
| 2026-06-06 00:00 |
02:58:46.68 |
-10:03:22.6 |
HIP 13883 |
16.79 |
| 2026-06-06 12:00 |
02:58:48.98 |
-10:03:21.6 |
HIP 13883 |
16.78 |
| 2026-06-07 00:00 |
02:58:51.28 |
-10:03:20.9 |
HIP 13883 |
16.79 |
| 2026-06-07 12:00 |
02:58:53.57 |
-10:03:20.3 |
HIP 13883 |
16.82 |
| 2026-06-08 00:00 |
02:58:55.85 |
-10:03:19.9 |
HIP 13883 |
16.88 |
| 2026-06-08 12:00 |
02:58:58.11 |
-10:03:19.7 |
HIP 13883 |
16.95 |
| 2026-06-09 00:00 |
02:59:00.37 |
-10:03:19.6 |
HIP 13883 |
17.05 |
| 2026-06-09 12:00 |
02:59:02.62 |
-10:03:19.8 |
HIP 13883 |
17.16 |
| 2026-06-10 00:00 |
02:59:04.85 |
-10:03:20.0 |
HIP 13883 |
17.29 |
| 2026-06-10 12:00 |
02:59:07.08 |
-10:03:20.5 |
HIP 13883 |
17.45 |
| 2026-06-11 00:00 |
02:59:09.29 |
-10:03:21.1 |
HIP 13883 |
17.62 |
| 2026-06-11 12:00 |
02:59:11.50 |
-10:03:22.0 |
HIP 13883 |
17.80 |
| 2026-06-12 00:00 |
02:59:13.69 |
-10:03:22.9 |
HIP 13883 |
18.01 |
| 2026-06-12 12:00 |
02:59:15.87 |
-10:03:24.1 |
HIP 13883 |
18.23 |
| 2026-06-13 00:00 |
02:59:18.04 |
-10:03:25.4 |
HIP 13883 |
18.46 |
| 2026-06-13 12:00 |
02:59:20.20 |
-10:03:26.9 |
HIP 13883 |
18.71 |
| 2026-06-14 00:00 |
02:59:22.35 |
-10:03:28.6 |
HIP 13883 |
18.97 |
| 2026-06-14 12:00 |
02:59:24.48 |
-10:03:30.5 |
HIP 13883 |
19.24 |
| 2026-06-15 00:00 |
02:59:26.60 |
-10:03:32.5 |
HIP 13883 |
19.52 |
| 2026-06-15 12:00 |
02:59:28.71 |
-10:03:34.7 |
HIP 13883 |
19.82 |
| 2026-06-16 00:00 |
02:59:30.81 |
-10:03:37.1 |
HIP 13883 |
20.12 |
| 2026-06-16 12:00 |
02:59:32.89 |
-10:03:39.6 |
HIP 14050 |
20.09 |
| 2026-06-17 00:00 |
02:59:34.96 |
-10:03:42.4 |
HIP 14050 |
19.58 |
| 2026-06-17 12:00 |
02:59:37.02 |
-10:03:45.3 |
HIP 14050 |
19.08 |
| 2026-06-18 00:00 |
02:59:39.07 |
-10:03:48.3 |
HIP 14050 |
18.58 |
| 2026-06-18 12:00 |
02:59:41.10 |
-10:03:51.6 |
HIP 14050 |
18.09 |
| 2026-06-19 00:00 |
02:59:43.12 |
-10:03:55.0 |
HIP 14050 |
17.60 |
| 2026-06-19 12:00 |
02:59:45.12 |
-10:03:58.6 |
HIP 14050 |
17.12 |
| 2026-06-20 00:00 |
02:59:47.11 |
-10:04:02.3 |
HIP 14050 |
16.64 |
| 2026-06-20 12:00 |
02:59:49.09 |
-10:04:06.2 |
HIP 14050 |
16.16 |
| 2026-06-21 00:00 |
02:59:51.06 |
-10:04:10.3 |
HIP 14050 |
15.69 |
| 2026-06-21 12:00 |
02:59:53.01 |
-10:04:14.6 |
HIP 14050 |
15.23 |
| 2026-06-22 00:00 |
02:59:54.94 |
-10:04:19.0 |
HIP 14050 |
14.76 |