メタデータ
| 項目 |
値 |
| Designation |
318P/McNaught-Hartley |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2015-10-21T00:27:13.642560Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:28:23Z |
| Obs used |
442 |
| NEO |
- |
| M1 |
9.600 |
| K1 |
13.500 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2012-04-13.0000000 |
| e |
0.67524420 |
| q (au) |
2.445459 |
| a (au) |
7.530148 |
| i (deg) |
17.894853 |
| Ω (om, deg) |
35.754310 |
| ω (w, deg) |
313.177220 |
| M (ma, deg) |
298.659661 |
等級
散乱 + 全体線形
$$
M_a = (10.986 + 4.792\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
10.986 |
| n |
4.792 |
| gf |
1.000 |
| gb |
-0.500 |
| k |
0.800 |
| δ90 |
2.293 |
| 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) |
| 2026-05-12 00:00 |
11:34:23.33 |
+17:05:55.0 |
HIP 56476 |
6.63 |
| 2026-05-12 12:00 |
11:34:19.64 |
+17:05:41.0 |
HIP 56476 |
7.17 |
| 2026-05-13 00:00 |
11:34:16.03 |
+17:05:26.4 |
HIP 56476 |
7.76 |
| 2026-05-13 12:00 |
11:34:12.50 |
+17:05:11.3 |
HIP 56476 |
8.39 |
| 2026-05-14 00:00 |
11:34:09.03 |
+17:04:55.6 |
HIP 56476 |
9.04 |
| 2026-05-14 12:00 |
11:34:05.64 |
+17:04:39.4 |
HIP 56476 |
9.70 |
| 2026-05-15 00:00 |
11:34:02.32 |
+17:04:22.6 |
HIP 56476 |
10.38 |
| 2026-05-15 12:00 |
11:33:59.08 |
+17:04:05.3 |
HIP 56476 |
11.05 |
| 2026-05-16 00:00 |
11:33:55.90 |
+17:03:47.4 |
HIP 56476 |
11.73 |
| 2026-05-16 12:00 |
11:33:52.80 |
+17:03:29.0 |
HIP 56476 |
12.41 |
| 2026-05-17 00:00 |
11:33:49.78 |
+17:03:10.0 |
HIP 56476 |
13.08 |
| 2026-05-17 12:00 |
11:33:46.83 |
+17:02:50.6 |
HIP 56476 |
13.74 |
| 2026-05-18 00:00 |
11:33:43.95 |
+17:02:30.5 |
HIP 56476 |
14.40 |
| 2026-05-18 12:00 |
11:33:41.15 |
+17:02:10.0 |
HIP 56476 |
15.05 |
| 2026-05-19 00:00 |
11:33:38.42 |
+17:01:48.9 |
HIP 56476 |
15.69 |
| 2026-05-19 12:00 |
11:33:35.77 |
+17:01:27.3 |
HIP 56476 |
16.32 |
| 2026-05-20 00:00 |
11:33:33.20 |
+17:01:05.2 |
HIP 56476 |
16.94 |
| 2026-05-20 12:00 |
11:33:30.69 |
+17:00:42.5 |
HIP 56476 |
17.55 |
| 2026-05-21 00:00 |
11:33:28.27 |
+17:00:19.3 |
HIP 56476 |
18.15 |
| 2026-05-21 12:00 |
11:33:25.91 |
+16:59:55.6 |
HIP 56476 |
18.74 |
| 2026-05-22 00:00 |
11:33:23.64 |
+16:59:31.4 |
HIP 56476 |
19.32 |
| 2026-05-22 12:00 |
11:33:21.44 |
+16:59:06.6 |
HIP 56476 |
19.89 |
| 2026-05-23 00:00 |
11:33:19.31 |
+16:58:41.4 |
HIP 56476 |
20.45 |
| 2026-05-23 12:00 |
11:33:17.26 |
+16:58:15.6 |
HIP 56476 |
21.00 |
| 2026-05-24 00:00 |
11:33:15.29 |
+16:57:49.4 |
HIP 56476 |
21.54 |
| 2026-05-24 12:00 |
11:33:13.39 |
+16:57:22.6 |
HIP 56476 |
22.07 |
| 2026-05-25 00:00 |
11:33:11.56 |
+16:56:55.3 |
HIP 56476 |
22.58 |
| 2026-05-25 12:00 |
11:33:09.82 |
+16:56:27.5 |
HIP 56476 |
23.09 |
| 2026-05-26 00:00 |
11:33:08.14 |
+16:55:59.3 |
HIP 56476 |
23.59 |
| 2026-05-26 12:00 |
11:33:06.55 |
+16:55:30.5 |
HIP 56476 |
24.07 |
| 2026-05-27 00:00 |
11:33:05.02 |
+16:55:01.3 |
HIP 56473 |
24.41 |
| 2026-05-27 12:00 |
11:33:03.58 |
+16:54:31.5 |
HIP 56473 |
24.60 |
| 2026-05-28 00:00 |
11:33:02.21 |
+16:54:01.3 |
HIP 56473 |
24.79 |
| 2026-05-28 12:00 |
11:33:00.91 |
+16:53:30.6 |
HIP 56473 |
24.96 |
| 2026-05-29 00:00 |
11:32:59.69 |
+16:52:59.4 |
HIP 56473 |
25.14 |
| 2026-05-29 12:00 |
11:32:58.55 |
+16:52:27.8 |
HIP 56473 |
25.30 |
| 2026-05-30 00:00 |
11:32:57.48 |
+16:51:55.6 |
HIP 56473 |
25.46 |
| 2026-05-30 12:00 |
11:32:56.49 |
+16:51:23.0 |
HIP 56473 |
25.62 |
| 2026-05-31 00:00 |
11:32:55.57 |
+16:50:49.9 |
HIP 56473 |
25.76 |
| 2026-05-31 12:00 |
11:32:54.73 |
+16:50:16.4 |
HIP 56473 |
25.91 |
| 2026-06-01 00:00 |
11:32:53.96 |
+16:49:42.4 |
HIP 56473 |
26.04 |
| 2026-06-01 12:00 |
11:32:53.27 |
+16:49:07.9 |
HIP 56473 |
26.17 |
| 2026-06-02 00:00 |
11:32:52.66 |
+16:48:33.0 |
HIP 56473 |
26.30 |