メタデータ
| 項目 |
値 |
| Designation |
278P/McNaught |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2013-08-02T10:27:33.508800Z |
| Orbit solution date (soln_date, UTC) |
2021-09-20T00:13:08Z |
| Obs used |
519 |
| NEO |
- |
| M1 |
12.600 |
| K1 |
13.750 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2015-06-08.0000000 |
| e |
0.43343798 |
| q (au) |
2.096064 |
| a (au) |
3.699620 |
| i (deg) |
6.683671 |
| Ω (om, deg) |
15.492573 |
| ω (w, deg) |
237.922750 |
| M (ma, deg) |
93.431156 |
等級
散乱 + 全体線形
$$
M_a = (10.947 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
10.947 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.946 |
| 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) |
| 2026-07-29 00:00 |
09:26:13.56 |
+19:13:06.9 |
HIP 46304 |
10.73 |
| 2026-07-29 12:00 |
09:26:51.29 |
+19:09:48.6 |
HIP 46304 |
7.38 |
| 2026-07-30 00:00 |
09:27:29.06 |
+19:06:29.8 |
HIP 46304 |
13.22 |
| 2026-07-30 12:00 |
09:28:06.86 |
+19:03:10.4 |
HIP 46501 |
19.00 |
| 2026-07-31 00:00 |
09:28:44.70 |
+18:59:50.5 |
HIP 46570 |
16.62 |
| 2026-07-31 12:00 |
09:29:22.57 |
+18:56:30.0 |
HIP 46570 |
11.48 |
| 2026-08-01 00:00 |
09:30:00.48 |
+18:53:09.0 |
HIP 46570 |
13.05 |
| 2026-08-01 12:00 |
09:30:38.42 |
+18:49:47.4 |
HIP 46570 |
19.80 |
| 2026-08-02 00:00 |
09:31:16.39 |
+18:46:25.3 |
HIP 46570 |
28.26 |
| 2026-08-02 12:00 |
09:31:54.40 |
+18:43:02.7 |
HIP 46910 |
24.70 |
| 2026-08-03 00:00 |
09:32:32.44 |
+18:39:39.5 |
HIP 46910 |
16.31 |
| 2026-08-03 12:00 |
09:33:10.51 |
+18:36:15.8 |
HIP 46910 |
10.36 |
| 2026-08-04 00:00 |
09:33:48.62 |
+18:32:51.5 |
HIP 46910 |
11.58 |
| 2026-08-04 12:00 |
09:34:26.75 |
+18:29:26.7 |
HIP 46910 |
18.65 |
| 2026-08-05 00:00 |
09:35:04.92 |
+18:26:01.4 |
HIP 46900 |
24.90 |
| 2026-08-05 12:00 |
09:35:43.12 |
+18:22:35.5 |
HIP 46986 |
29.29 |
| 2026-08-06 00:00 |
09:36:21.35 |
+18:19:09.1 |
HIP 47278 |
31.59 |
| 2026-08-06 12:00 |
09:36:59.61 |
+18:15:42.1 |
HIP 47278 |
27.79 |
| 2026-08-07 00:00 |
09:37:37.90 |
+18:12:14.7 |
HIP 47278 |
27.13 |
| 2026-08-07 12:00 |
09:38:16.21 |
+18:08:46.7 |
HIP 47278 |
29.81 |
| 2026-08-08 00:00 |
09:38:54.56 |
+18:05:18.2 |
HIP 47504 |
32.52 |
| 2026-08-08 12:00 |
09:39:32.94 |
+18:01:49.1 |
HIP 47504 |
22.80 |
| 2026-08-09 00:00 |
09:40:11.34 |
+17:58:19.5 |
HIP 47504 |
13.15 |
| 2026-08-09 12:00 |
09:40:49.77 |
+17:54:49.4 |
HIP 47504 |
4.12 |
| 2026-08-10 00:00 |
09:41:28.23 |
+17:51:18.8 |
HIP 47504 |
7.27 |
| 2026-08-10 12:00 |
09:42:06.71 |
+17:47:47.7 |
HIP 47667 |
15.52 |
| 2026-08-11 00:00 |
09:42:45.22 |
+17:44:16.1 |
HIP 47667 |
6.49 |
| 2026-08-11 12:00 |
09:43:23.76 |
+17:40:43.9 |
HIP 47667 |
6.02 |
| 2026-08-12 00:00 |
09:44:02.32 |
+17:37:11.2 |
HIP 47745 |
3.24 |
| 2026-08-12 12:00 |
09:44:40.91 |
+17:33:38.1 |
HIP 47745 |
11.68 |
| 2026-08-13 00:00 |
09:45:19.52 |
+17:30:04.4 |
HIP 47745 |
21.38 |
| 2026-08-13 12:00 |
09:45:58.15 |
+17:26:30.3 |
HIP 47927 |
26.85 |
| 2026-08-14 00:00 |
09:46:36.80 |
+17:22:55.6 |
HIP 47927 |
31.59 |
| 2026-08-14 12:00 |
09:47:15.48 |
+17:19:20.4 |
HIP 47927 |
38.35 |
| 2026-08-15 00:00 |
09:47:54.18 |
+17:15:44.8 |
HIP 48220 |
38.10 |
| 2026-08-15 12:00 |
09:48:32.89 |
+17:12:08.7 |
HIP 48220 |
29.01 |
| 2026-08-16 00:00 |
09:49:11.63 |
+17:08:32.1 |
HIP 48220 |
20.71 |
| 2026-08-16 12:00 |
09:49:50.39 |
+17:04:55.0 |
HIP 48220 |
14.62 |
| 2026-08-17 00:00 |
09:50:29.17 |
+17:01:17.4 |
HIP 48220 |
14.00 |
| 2026-08-17 12:00 |
09:51:07.97 |
+16:57:39.4 |
HIP 48220 |
19.42 |
| 2026-08-18 00:00 |
09:51:46.79 |
+16:54:00.8 |
HIP 48504 |
25.10 |
| 2026-08-18 12:00 |
09:52:25.62 |
+16:50:21.9 |
HIP 48504 |
17.00 |
| 2026-08-19 00:00 |
09:53:04.47 |
+16:46:42.4 |
HIP 48504 |
12.12 |