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) |
| 2026-03-26 00:00 |
17:54:55.97 |
-15:10:16.8 |
HIP 87640 |
19.83 |
| 2026-03-26 12:00 |
17:54:55.72 |
-15:09:59.0 |
HIP 87640 |
19.56 |
| 2026-03-27 00:00 |
17:54:55.42 |
-15:09:41.2 |
HIP 87640 |
19.28 |
| 2026-03-27 12:00 |
17:54:55.05 |
-15:09:23.3 |
HIP 87640 |
18.99 |
| 2026-03-28 00:00 |
17:54:54.63 |
-15:09:05.5 |
HIP 87640 |
18.70 |
| 2026-03-28 12:00 |
17:54:54.14 |
-15:08:47.6 |
HIP 87640 |
18.39 |
| 2026-03-29 00:00 |
17:54:53.60 |
-15:08:29.8 |
HIP 87640 |
18.08 |
| 2026-03-29 12:00 |
17:54:52.99 |
-15:08:11.9 |
HIP 87640 |
17.75 |
| 2026-03-30 00:00 |
17:54:52.32 |
-15:07:54.0 |
HIP 87640 |
17.42 |
| 2026-03-30 12:00 |
17:54:51.60 |
-15:07:36.1 |
HIP 87640 |
17.08 |
| 2026-03-31 00:00 |
17:54:50.81 |
-15:07:18.3 |
HIP 87640 |
16.73 |
| 2026-03-31 12:00 |
17:54:49.96 |
-15:07:00.4 |
HIP 87640 |
16.37 |
| 2026-04-01 00:00 |
17:54:49.06 |
-15:06:42.5 |
HIP 87640 |
16.00 |
| 2026-04-01 12:00 |
17:54:48.09 |
-15:06:24.7 |
HIP 87640 |
15.62 |
| 2026-04-02 00:00 |
17:54:47.06 |
-15:06:06.8 |
HIP 87640 |
15.24 |
| 2026-04-02 12:00 |
17:54:45.98 |
-15:05:48.9 |
HIP 87640 |
14.84 |
| 2026-04-03 00:00 |
17:54:44.83 |
-15:05:31.1 |
HIP 87640 |
14.43 |
| 2026-04-03 12:00 |
17:54:43.62 |
-15:05:13.2 |
HIP 87640 |
14.02 |
| 2026-04-04 00:00 |
17:54:42.36 |
-15:04:55.3 |
HIP 87640 |
13.59 |
| 2026-04-04 12:00 |
17:54:41.03 |
-15:04:37.5 |
HIP 87640 |
13.16 |
| 2026-04-05 00:00 |
17:54:39.64 |
-15:04:19.7 |
HIP 87640 |
12.72 |
| 2026-04-05 12:00 |
17:54:38.20 |
-15:04:01.8 |
HIP 87640 |
12.27 |
| 2026-04-06 00:00 |
17:54:36.69 |
-15:03:44.0 |
HIP 87640 |
11.81 |
| 2026-04-06 12:00 |
17:54:35.13 |
-15:03:26.2 |
HIP 87640 |
11.34 |
| 2026-04-07 00:00 |
17:54:33.50 |
-15:03:08.4 |
HIP 87640 |
10.87 |
| 2026-04-07 12:00 |
17:54:31.82 |
-15:02:50.6 |
HIP 87640 |
10.39 |
| 2026-04-08 00:00 |
17:54:30.08 |
-15:02:32.9 |
HIP 87640 |
9.90 |
| 2026-04-08 12:00 |
17:54:28.28 |
-15:02:15.1 |
HIP 87640 |
9.41 |
| 2026-04-09 00:00 |
17:54:26.42 |
-15:01:57.4 |
HIP 87640 |
8.92 |
| 2026-04-09 12:00 |
17:54:24.50 |
-15:01:39.7 |
HIP 87640 |
8.42 |
| 2026-04-10 00:00 |
17:54:22.52 |
-15:01:22.0 |
HIP 87640 |
7.92 |
| 2026-04-10 12:00 |
17:54:20.48 |
-15:01:04.3 |
HIP 87640 |
7.43 |
| 2026-04-11 00:00 |
17:54:18.38 |
-15:00:46.7 |
HIP 87640 |
6.94 |
| 2026-04-11 12:00 |
17:54:16.23 |
-15:00:29.0 |
HIP 87640 |
6.47 |
| 2026-04-12 00:00 |
17:54:14.02 |
-15:00:11.4 |
HIP 87640 |
6.01 |
| 2026-04-12 12:00 |
17:54:11.74 |
-14:59:53.8 |
HIP 87640 |
5.58 |
| 2026-04-13 00:00 |
17:54:09.41 |
-14:59:36.3 |
HIP 87640 |
5.18 |
| 2026-04-13 12:00 |
17:54:07.03 |
-14:59:18.7 |
HIP 87640 |
4.84 |
| 2026-04-14 00:00 |
17:54:04.58 |
-14:59:01.2 |
HIP 87640 |
4.57 |
| 2026-04-14 12:00 |
17:54:02.08 |
-14:58:43.7 |
HIP 87640 |
4.38 |
| 2026-04-15 00:00 |
17:53:59.51 |
-14:58:26.3 |
HIP 87640 |
4.30 |
| 2026-04-15 12:00 |
17:53:56.89 |
-14:58:08.9 |
HIP 87640 |
4.33 |
| 2026-04-16 00:00 |
17:53:54.22 |
-14:57:51.5 |
HIP 87640 |
4.48 |