メタデータ
| 項目 |
値 |
| Designation |
18D/Perrine-Mrkos |
| Type |
D |
| Perihelion (tp_cal, UTC) |
1968-11-01T13:00:40.325760Z |
| Orbit solution date (soln_date, UTC) |
2002-02-22T17:02:43Z |
| Obs used |
16 |
| NEO |
Yes |
| M1 |
11.500 |
| K1 |
20.000 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
1969-01-19.0000000 |
| e |
0.64258098 |
| q (au) |
1.272248 |
| a (au) |
3.559542 |
| i (deg) |
17.758983 |
| Ω (om, deg) |
240.875547 |
| ω (w, deg) |
166.050417 |
| M (ma, deg) |
11.514613 |
等級
散乱 + 全体線形
$$
M_a = (12.123 + 4.437\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
12.123 |
| n |
4.437 |
| 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
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-09-20 00:00 |
11:28:20.32 |
-10:00:03.2 |
HIP 56077 |
19.42 |
| 2026-09-20 12:00 |
11:28:46.18 |
-10:02:40.2 |
HIP 56077 |
12.74 |
| 2026-09-21 00:00 |
11:29:12.02 |
-10:05:17.5 |
HIP 56077 |
6.52 |
| 2026-09-21 12:00 |
11:29:37.83 |
-10:07:55.1 |
HIP 56077 |
4.16 |
| 2026-09-22 00:00 |
11:30:03.61 |
-10:10:32.9 |
HIP 56077 |
9.31 |
| 2026-09-22 12:00 |
11:30:29.36 |
-10:13:11.0 |
HIP 56213 |
13.95 |
| 2026-09-23 00:00 |
11:30:55.08 |
-10:15:49.4 |
HIP 56213 |
7.30 |
| 2026-09-23 12:00 |
11:31:20.78 |
-10:18:28.0 |
HIP 56213 |
2.45 |
| 2026-09-24 00:00 |
11:31:46.44 |
-10:21:06.8 |
HIP 56213 |
7.25 |
| 2026-09-24 12:00 |
11:32:12.08 |
-10:23:45.9 |
HIP 56254 |
12.59 |
| 2026-09-25 00:00 |
11:32:37.69 |
-10:26:25.3 |
HIP 56254 |
14.45 |
| 2026-09-25 12:00 |
11:33:03.26 |
-10:29:04.8 |
HIP 56254 |
18.76 |
| 2026-09-26 00:00 |
11:33:28.81 |
-10:31:44.6 |
HIP 56254 |
24.25 |
| 2026-09-26 12:00 |
11:33:54.32 |
-10:34:24.6 |
HIP 56254 |
30.28 |
| 2026-09-27 00:00 |
11:34:19.80 |
-10:37:04.9 |
HIP 56611 |
32.68 |
| 2026-09-27 12:00 |
11:34:45.25 |
-10:39:45.4 |
HIP 56611 |
28.06 |
| 2026-09-28 00:00 |
11:35:10.67 |
-10:42:26.0 |
HIP 56611 |
24.50 |
| 2026-09-28 12:00 |
11:35:36.05 |
-10:45:06.9 |
HIP 56611 |
22.48 |
| 2026-09-29 00:00 |
11:36:01.40 |
-10:47:48.0 |
HIP 56611 |
22.43 |
| 2026-09-29 12:00 |
11:36:26.72 |
-10:50:29.4 |
HIP 56611 |
24.35 |
| 2026-09-30 00:00 |
11:36:52.00 |
-10:53:10.9 |
HIP 56778 |
23.50 |
| 2026-09-30 12:00 |
11:37:17.25 |
-10:55:52.6 |
HIP 56778 |
17.16 |
| 2026-10-01 00:00 |
11:37:42.46 |
-10:58:34.5 |
HIP 56778 |
11.30 |
| 2026-10-01 12:00 |
11:38:07.63 |
-11:01:16.6 |
HIP 56778 |
7.25 |
| 2026-10-02 00:00 |
11:38:32.77 |
-11:03:58.8 |
HIP 56778 |
8.27 |
| 2026-10-02 12:00 |
11:38:57.87 |
-11:06:41.3 |
HIP 56798 |
9.06 |
| 2026-10-03 00:00 |
11:39:22.94 |
-11:09:23.9 |
HIP 56798 |
12.04 |
| 2026-10-03 12:00 |
11:39:47.96 |
-11:12:06.8 |
HIP 56798 |
17.26 |
| 2026-10-04 00:00 |
11:40:12.95 |
-11:14:49.7 |
HIP 56798 |
23.24 |
| 2026-10-04 12:00 |
11:40:37.90 |
-11:17:32.9 |
HIP 56798 |
29.52 |
| 2026-10-05 00:00 |
11:41:02.80 |
-11:20:16.2 |
HIP 57105 |
22.86 |
| 2026-10-05 12:00 |
11:41:27.67 |
-11:22:59.6 |
HIP 57105 |
16.21 |
| 2026-10-06 00:00 |
11:41:52.49 |
-11:25:43.2 |
HIP 57105 |
9.60 |
| 2026-10-06 12:00 |
11:42:17.28 |
-11:28:27.0 |
HIP 57105 |
3.24 |
| 2026-10-07 00:00 |
11:42:42.02 |
-11:31:10.9 |
HIP 57105 |
4.16 |
| 2026-10-07 12:00 |
11:43:06.71 |
-11:33:54.9 |
HIP 57105 |
10.60 |
| 2026-10-08 00:00 |
11:43:31.37 |
-11:36:39.1 |
HIP 57105 |
17.18 |
| 2026-10-08 12:00 |
11:43:55.98 |
-11:39:23.4 |
HIP 57281 |
16.34 |
| 2026-10-09 00:00 |
11:44:20.54 |
-11:42:07.8 |
HIP 57281 |
15.09 |
| 2026-10-09 12:00 |
11:44:45.06 |
-11:44:52.3 |
HIP 57281 |
16.60 |
| 2026-10-10 00:00 |
11:45:09.53 |
-11:47:36.9 |
HIP 57281 |
20.26 |
| 2026-10-10 12:00 |
11:45:33.95 |
-11:50:21.6 |
HIP 57414 |
14.98 |
| 2026-10-11 00:00 |
11:45:58.32 |
-11:53:06.4 |
HIP 57414 |
9.33 |