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) |
| 2026-03-26 00:00 |
09:50:38.54 |
-09:25:47.3 |
HIP 48431 |
29.32 |
| 2026-03-26 12:00 |
09:50:26.58 |
-09:22:27.0 |
HIP 48431 |
30.96 |
| 2026-03-27 00:00 |
09:50:14.88 |
-09:19:07.0 |
HIP 48184 |
32.31 |
| 2026-03-27 12:00 |
09:50:03.43 |
-09:15:47.3 |
HIP 48184 |
28.10 |
| 2026-03-28 00:00 |
09:49:52.24 |
-09:12:28.1 |
HIP 48184 |
23.97 |
| 2026-03-28 12:00 |
09:49:41.30 |
-09:09:09.3 |
HIP 48184 |
19.95 |
| 2026-03-29 00:00 |
09:49:30.61 |
-09:05:51.0 |
HIP 48184 |
16.09 |
| 2026-03-29 12:00 |
09:49:20.17 |
-09:02:33.1 |
HIP 48184 |
12.47 |
| 2026-03-30 00:00 |
09:49:10.00 |
-08:59:15.8 |
HIP 48184 |
9.33 |
| 2026-03-30 12:00 |
09:49:00.07 |
-08:55:59.0 |
HIP 48184 |
7.25 |
| 2026-03-31 00:00 |
09:48:50.41 |
-08:52:42.8 |
HIP 48184 |
7.13 |
| 2026-03-31 12:00 |
09:48:41.00 |
-08:49:27.2 |
HIP 48184 |
8.98 |
| 2026-04-01 00:00 |
09:48:31.84 |
-08:46:12.3 |
HIP 48184 |
11.88 |
| 2026-04-01 12:00 |
09:48:22.95 |
-08:42:57.9 |
HIP 48184 |
15.20 |
| 2026-04-02 00:00 |
09:48:14.31 |
-08:39:44.3 |
HIP 48062 |
11.65 |
| 2026-04-02 12:00 |
09:48:05.93 |
-08:36:31.3 |
HIP 48062 |
7.83 |
| 2026-04-03 00:00 |
09:47:57.80 |
-08:33:19.1 |
HIP 48062 |
4.07 |
| 2026-04-03 12:00 |
09:47:49.94 |
-08:30:07.6 |
HIP 48062 |
0.64 |
| 2026-04-04 00:00 |
09:47:42.33 |
-08:26:56.9 |
HIP 48062 |
3.43 |
| 2026-04-04 12:00 |
09:47:34.98 |
-08:23:47.0 |
HIP 48062 |
7.06 |
| 2026-04-05 00:00 |
09:47:27.89 |
-08:20:37.9 |
HIP 48062 |
10.65 |
| 2026-04-05 12:00 |
09:47:21.05 |
-08:17:29.6 |
HIP 48076 |
12.90 |
| 2026-04-06 00:00 |
09:47:14.48 |
-08:14:22.2 |
HIP 48076 |
12.93 |
| 2026-04-06 12:00 |
09:47:08.16 |
-08:11:15.7 |
HIP 48076 |
13.83 |
| 2026-04-07 00:00 |
09:47:02.10 |
-08:08:10.0 |
HIP 48076 |
15.40 |
| 2026-04-07 12:00 |
09:46:56.30 |
-08:05:05.3 |
HIP 48076 |
17.45 |
| 2026-04-08 00:00 |
09:46:50.76 |
-08:02:01.6 |
HIP 48076 |
19.81 |
| 2026-04-08 12:00 |
09:46:45.47 |
-07:58:58.8 |
HIP 48076 |
22.37 |
| 2026-04-09 00:00 |
09:46:40.44 |
-07:55:57.0 |
HIP 48076 |
25.04 |
| 2026-04-09 12:00 |
09:46:35.67 |
-07:52:56.2 |
HIP 48076 |
27.78 |
| 2026-04-10 00:00 |
09:46:31.16 |
-07:49:56.4 |
HIP 48076 |
30.55 |
| 2026-04-10 12:00 |
09:46:26.91 |
-07:46:57.7 |
HIP 48076 |
33.35 |
| 2026-04-11 00:00 |
09:46:22.91 |
-07:44:00.0 |
HIP 48076 |
36.15 |
| 2026-04-11 12:00 |
09:46:19.16 |
-07:41:03.4 |
HIP 47977 |
34.10 |
| 2026-04-12 00:00 |
09:46:15.68 |
-07:38:07.9 |
HIP 47977 |
31.43 |
| 2026-04-12 12:00 |
09:46:12.45 |
-07:35:13.5 |
HIP 47977 |
28.83 |
| 2026-04-13 00:00 |
09:46:09.47 |
-07:32:20.3 |
HIP 47977 |
26.32 |
| 2026-04-13 12:00 |
09:46:06.75 |
-07:29:28.2 |
HIP 47977 |
23.91 |
| 2026-04-14 00:00 |
09:46:04.28 |
-07:26:37.2 |
HIP 47977 |
21.62 |
| 2026-04-14 12:00 |
09:46:02.07 |
-07:23:47.5 |
HIP 47977 |
19.47 |
| 2026-04-15 00:00 |
09:46:00.11 |
-07:20:59.0 |
HIP 47977 |
17.52 |
| 2026-04-15 12:00 |
09:45:58.41 |
-07:18:11.6 |
HIP 47977 |
15.80 |
| 2026-04-16 00:00 |
09:45:56.95 |
-07:15:25.6 |
HIP 47977 |
14.39 |