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) |
| 2026-05-12 00:00 |
17:50:22.97 |
-14:43:57.5 |
HIP 87444 |
30.14 |
| 2026-05-12 12:00 |
17:50:17.67 |
-14:43:43.2 |
HIP 87288 |
29.90 |
| 2026-05-13 00:00 |
17:50:12.34 |
-14:43:29.1 |
HIP 87288 |
29.60 |
| 2026-05-13 12:00 |
17:50:06.96 |
-14:43:15.0 |
HIP 87288 |
29.35 |
| 2026-05-14 00:00 |
17:50:01.55 |
-14:43:01.0 |
HIP 87288 |
29.17 |
| 2026-05-14 12:00 |
17:49:56.10 |
-14:42:47.0 |
HIP 87288 |
29.04 |
| 2026-05-15 00:00 |
17:49:50.61 |
-14:42:33.2 |
HIP 87288 |
28.99 |
| 2026-05-15 12:00 |
17:49:45.08 |
-14:42:19.4 |
HIP 87288 |
28.99 |
| 2026-05-16 00:00 |
17:49:39.52 |
-14:42:05.8 |
HIP 87288 |
29.07 |
| 2026-05-16 12:00 |
17:49:33.92 |
-14:41:52.2 |
HIP 87074 |
28.37 |
| 2026-05-17 00:00 |
17:49:28.28 |
-14:41:38.7 |
HIP 87074 |
27.03 |
| 2026-05-17 12:00 |
17:49:22.61 |
-14:41:25.4 |
HIP 87074 |
25.67 |
| 2026-05-18 00:00 |
17:49:16.90 |
-14:41:12.1 |
HIP 87074 |
24.32 |
| 2026-05-18 12:00 |
17:49:11.16 |
-14:40:58.9 |
HIP 87074 |
22.96 |
| 2026-05-19 00:00 |
17:49:05.38 |
-14:40:45.8 |
HIP 87074 |
21.60 |
| 2026-05-19 12:00 |
17:48:59.57 |
-14:40:32.7 |
HIP 87074 |
20.24 |
| 2026-05-20 00:00 |
17:48:53.73 |
-14:40:19.8 |
HIP 87074 |
18.88 |
| 2026-05-20 12:00 |
17:48:47.85 |
-14:40:07.0 |
HIP 87074 |
17.52 |
| 2026-05-21 00:00 |
17:48:41.95 |
-14:39:54.3 |
HIP 87074 |
16.17 |
| 2026-05-21 12:00 |
17:48:36.01 |
-14:39:41.7 |
HIP 87074 |
14.83 |
| 2026-05-22 00:00 |
17:48:30.04 |
-14:39:29.1 |
HIP 87074 |
13.50 |
| 2026-05-22 12:00 |
17:48:24.04 |
-14:39:16.7 |
HIP 87074 |
12.20 |
| 2026-05-23 00:00 |
17:48:18.01 |
-14:39:04.4 |
HIP 87074 |
10.93 |
| 2026-05-23 12:00 |
17:48:11.96 |
-14:38:52.1 |
HIP 87074 |
9.71 |
| 2026-05-24 00:00 |
17:48:05.87 |
-14:38:40.0 |
HIP 87074 |
8.56 |
| 2026-05-24 12:00 |
17:47:59.76 |
-14:38:28.0 |
HIP 87074 |
7.53 |
| 2026-05-25 00:00 |
17:47:53.62 |
-14:38:16.0 |
HIP 87074 |
6.67 |
| 2026-05-25 12:00 |
17:47:47.45 |
-14:38:04.2 |
HIP 87074 |
6.05 |
| 2026-05-26 00:00 |
17:47:41.25 |
-14:37:52.5 |
HIP 87074 |
5.77 |
| 2026-05-26 12:00 |
17:47:35.03 |
-14:37:40.9 |
HIP 87074 |
5.88 |
| 2026-05-27 00:00 |
17:47:28.79 |
-14:37:29.4 |
HIP 87074 |
6.36 |
| 2026-05-27 12:00 |
17:47:22.52 |
-14:37:18.0 |
HIP 87074 |
7.14 |
| 2026-05-28 00:00 |
17:47:16.22 |
-14:37:06.6 |
HIP 87074 |
8.13 |
| 2026-05-28 12:00 |
17:47:09.90 |
-14:36:55.4 |
HIP 87074 |
9.28 |
| 2026-05-29 00:00 |
17:47:03.56 |
-14:36:44.4 |
HIP 87074 |
10.53 |
| 2026-05-29 12:00 |
17:46:57.20 |
-14:36:33.4 |
HIP 86988 |
10.55 |
| 2026-05-30 00:00 |
17:46:50.81 |
-14:36:22.5 |
HIP 86988 |
9.97 |
| 2026-05-30 12:00 |
17:46:44.40 |
-14:36:11.7 |
HIP 86988 |
9.60 |
| 2026-05-31 00:00 |
17:46:37.97 |
-14:36:01.0 |
HIP 86988 |
9.48 |
| 2026-05-31 12:00 |
17:46:31.52 |
-14:35:50.5 |
HIP 86988 |
9.62 |
| 2026-06-01 00:00 |
17:46:25.05 |
-14:35:40.0 |
HIP 86988 |
10.00 |
| 2026-06-01 12:00 |
17:46:18.57 |
-14:35:29.7 |
HIP 86988 |
10.60 |
| 2026-06-02 00:00 |
17:46:12.06 |
-14:35:19.5 |
HIP 86988 |
11.39 |