メタデータ
| 項目 |
値 |
| Designation |
27P/Crommelin |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2011-08-02T13:37:41.877120Z |
| Orbit solution date (soln_date, UTC) |
2023-05-12T09:58:07Z |
| Obs used |
455 |
| NEO |
Yes |
| M1 |
12.700 |
| K1 |
27.750 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2002-08-03.0000000 |
| e |
0.91925987 |
| q (au) |
0.734210 |
| a (au) |
9.093497 |
| i (deg) |
29.221115 |
| Ω (om, deg) |
250.959353 |
| ω (w, deg) |
195.955445 |
| M (ma, deg) |
241.872697 |
等級
散乱 + 全体線形
$$
M_a = (15.302 + 5.211\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
15.302 |
| n |
5.211 |
| gf |
0.998 |
| gb |
-1.000 |
| k |
0.842 |
| δ90 |
9.969 |
| 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
残差 (区間線形)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| 開始日 (UTC) |
終了日 (UTC) |
a |
b |
| 2011-05-12 |
2011-07-25 |
+11.1741 |
-1.084 |
log10 r = log10(太陽距離/AU)、Δ = 地球距離(AU)
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-09-20 00:00 |
17:30:29.84 |
-14:45:15.6 |
HIP 85679 |
1.23 |
| 2026-09-20 12:00 |
17:30:30.82 |
-14:45:27.9 |
HIP 85679 |
0.95 |
| 2026-09-21 00:00 |
17:30:31.86 |
-14:45:40.1 |
HIP 85679 |
0.69 |
| 2026-09-21 12:00 |
17:30:32.95 |
-14:45:52.4 |
HIP 85679 |
0.52 |
| 2026-09-22 00:00 |
17:30:34.10 |
-14:46:04.7 |
HIP 85679 |
0.55 |
| 2026-09-22 12:00 |
17:30:35.31 |
-14:46:17.1 |
HIP 85679 |
0.77 |
| 2026-09-23 00:00 |
17:30:36.57 |
-14:46:29.4 |
HIP 85679 |
1.08 |
| 2026-09-23 12:00 |
17:30:37.90 |
-14:46:41.7 |
HIP 85679 |
1.43 |
| 2026-09-24 00:00 |
17:30:39.28 |
-14:46:54.1 |
HIP 85679 |
1.81 |
| 2026-09-24 12:00 |
17:30:40.72 |
-14:47:06.5 |
HIP 85679 |
2.20 |
| 2026-09-25 00:00 |
17:30:42.21 |
-14:47:18.9 |
HIP 85679 |
2.62 |
| 2026-09-25 12:00 |
17:30:43.76 |
-14:47:31.3 |
HIP 85679 |
3.04 |
| 2026-09-26 00:00 |
17:30:45.37 |
-14:47:43.7 |
HIP 85679 |
3.48 |
| 2026-09-26 12:00 |
17:30:47.04 |
-14:47:56.2 |
HIP 85679 |
3.93 |
| 2026-09-27 00:00 |
17:30:48.76 |
-14:48:08.6 |
HIP 85679 |
4.40 |
| 2026-09-27 12:00 |
17:30:50.53 |
-14:48:21.0 |
HIP 85679 |
4.87 |
| 2026-09-28 00:00 |
17:30:52.37 |
-14:48:33.5 |
HIP 85679 |
5.36 |
| 2026-09-28 12:00 |
17:30:54.26 |
-14:48:45.9 |
HIP 85679 |
5.86 |
| 2026-09-29 00:00 |
17:30:56.20 |
-14:48:58.4 |
HIP 85679 |
6.38 |
| 2026-09-29 12:00 |
17:30:58.21 |
-14:49:10.9 |
HIP 85679 |
6.90 |
| 2026-09-30 00:00 |
17:31:00.26 |
-14:49:23.3 |
HIP 85679 |
7.44 |
| 2026-09-30 12:00 |
17:31:02.38 |
-14:49:35.8 |
HIP 85679 |
7.99 |
| 2026-10-01 00:00 |
17:31:04.54 |
-14:49:48.3 |
HIP 85679 |
8.56 |
| 2026-10-01 12:00 |
17:31:06.77 |
-14:50:00.8 |
HIP 85679 |
9.13 |
| 2026-10-02 00:00 |
17:31:09.05 |
-14:50:13.2 |
HIP 85679 |
9.72 |
| 2026-10-02 12:00 |
17:31:11.38 |
-14:50:25.7 |
HIP 85679 |
10.32 |
| 2026-10-03 00:00 |
17:31:13.77 |
-14:50:38.2 |
HIP 85679 |
10.93 |
| 2026-10-03 12:00 |
17:31:16.21 |
-14:50:50.6 |
HIP 85679 |
11.56 |
| 2026-10-04 00:00 |
17:31:18.71 |
-14:51:03.1 |
HIP 85679 |
12.19 |
| 2026-10-04 12:00 |
17:31:21.26 |
-14:51:15.5 |
HIP 85679 |
12.84 |
| 2026-10-05 00:00 |
17:31:23.87 |
-14:51:27.9 |
HIP 85679 |
13.50 |
| 2026-10-05 12:00 |
17:31:26.53 |
-14:51:40.3 |
HIP 85679 |
14.18 |
| 2026-10-06 00:00 |
17:31:29.24 |
-14:51:52.8 |
HIP 85679 |
14.86 |
| 2026-10-06 12:00 |
17:31:32.01 |
-14:52:05.1 |
HIP 85679 |
15.56 |
| 2026-10-07 00:00 |
17:31:34.83 |
-14:52:17.5 |
HIP 85679 |
16.27 |
| 2026-10-07 12:00 |
17:31:37.70 |
-14:52:29.9 |
HIP 85679 |
16.99 |
| 2026-10-08 00:00 |
17:31:40.63 |
-14:52:42.2 |
HIP 85866 |
17.25 |
| 2026-10-08 12:00 |
17:31:43.61 |
-14:52:54.6 |
HIP 85866 |
16.63 |
| 2026-10-09 00:00 |
17:31:46.65 |
-14:53:06.9 |
HIP 85866 |
16.01 |
| 2026-10-09 12:00 |
17:31:49.73 |
-14:53:19.2 |
HIP 85866 |
15.39 |
| 2026-10-10 00:00 |
17:31:52.87 |
-14:53:31.4 |
HIP 85866 |
14.77 |
| 2026-10-10 12:00 |
17:31:56.06 |
-14:53:43.7 |
HIP 85866 |
14.16 |
| 2026-10-11 00:00 |
17:31:59.30 |
-14:53:55.9 |
HIP 85866 |
13.55 |