27P/Crommelin
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
$$
M_a = (15.356 + 5.575\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
15.356 |
| n |
5.575 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.800 |
| 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
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 |
+10.3055 |
-0.893 |
| 2011-12-27 |
2012-01-26 |
+23.2929 |
-10.145 |
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) |
| 2026-02-03 00:00 |
17:50:23.45 |
-15:36:30.7 |
HIP 87333 |
33.06 |
| 2026-02-03 12:00 |
17:50:28.61 |
-15:36:19.3 |
HIP 87333 |
33.10 |
| 2026-02-04 00:00 |
17:50:33.74 |
-15:36:07.7 |
HIP 87333 |
33.20 |
| 2026-02-04 12:00 |
17:50:38.83 |
-15:35:56.1 |
HIP 87333 |
33.34 |
| 2026-02-05 00:00 |
17:50:43.87 |
-15:35:44.3 |
HIP 87333 |
33.52 |
| 2026-02-05 12:00 |
17:50:48.88 |
-15:35:32.5 |
HIP 87333 |
33.75 |
| 2026-02-06 00:00 |
17:50:53.85 |
-15:35:20.5 |
HIP 87333 |
34.03 |
| 2026-02-06 12:00 |
17:50:58.77 |
-15:35:08.4 |
HIP 87333 |
34.34 |
| 2026-02-07 00:00 |
17:51:03.65 |
-15:34:56.3 |
HIP 87333 |
34.70 |
| 2026-02-07 12:00 |
17:51:08.49 |
-15:34:44.0 |
HIP 87574 |
33.60 |
| 2026-02-08 00:00 |
17:51:13.29 |
-15:34:31.6 |
HIP 87574 |
32.49 |
| 2026-02-08 12:00 |
17:51:18.05 |
-15:34:19.1 |
HIP 87574 |
31.39 |
| 2026-02-09 00:00 |
17:51:22.76 |
-15:34:06.6 |
HIP 87574 |
30.31 |
| 2026-02-09 12:00 |
17:51:27.43 |
-15:33:53.9 |
HIP 87574 |
29.24 |
| 2026-02-10 00:00 |
17:51:32.05 |
-15:33:41.1 |
HIP 87574 |
28.19 |
| 2026-02-10 12:00 |
17:51:36.63 |
-15:33:28.2 |
HIP 87574 |
27.16 |
| 2026-02-11 00:00 |
17:51:41.17 |
-15:33:15.3 |
HIP 87574 |
26.14 |
| 2026-02-11 12:00 |
17:51:45.66 |
-15:33:02.2 |
HIP 87574 |
25.15 |
| 2026-02-12 00:00 |
17:51:50.11 |
-15:32:49.0 |
HIP 87574 |
24.17 |
| 2026-02-12 12:00 |
17:51:54.51 |
-15:32:35.8 |
HIP 87574 |
23.22 |
| 2026-02-13 00:00 |
17:51:58.87 |
-15:32:22.4 |
HIP 87574 |
22.29 |
| 2026-02-13 12:00 |
17:52:03.18 |
-15:32:09.0 |
HIP 87574 |
21.38 |
| 2026-02-14 00:00 |
17:52:07.44 |
-15:31:55.5 |
HIP 87574 |
20.50 |
| 2026-02-14 12:00 |
17:52:11.66 |
-15:31:41.8 |
HIP 87574 |
19.65 |
| 2026-02-15 00:00 |
17:52:15.83 |
-15:31:28.1 |
HIP 87574 |
18.83 |
| 2026-02-15 12:00 |
17:52:19.95 |
-15:31:14.3 |
HIP 87574 |
18.03 |
| 2026-02-16 00:00 |
17:52:24.02 |
-15:31:00.4 |
HIP 87574 |
17.28 |
| 2026-02-16 12:00 |
17:52:28.05 |
-15:30:46.4 |
HIP 87574 |
16.56 |
| 2026-02-17 00:00 |
17:52:32.03 |
-15:30:32.4 |
HIP 87574 |
15.88 |
| 2026-02-17 12:00 |
17:52:35.96 |
-15:30:18.2 |
HIP 87574 |
15.24 |
| 2026-02-18 00:00 |
17:52:39.84 |
-15:30:04.0 |
HIP 87574 |
14.66 |
| 2026-02-18 12:00 |
17:52:43.67 |
-15:29:49.6 |
HIP 87574 |
14.12 |
| 2026-02-19 00:00 |
17:52:47.45 |
-15:29:35.2 |
HIP 87574 |
13.64 |
| 2026-02-19 12:00 |
17:52:51.18 |
-15:29:20.7 |
HIP 87574 |
13.22 |
| 2026-02-20 00:00 |
17:52:54.86 |
-15:29:06.2 |
HIP 87574 |
12.86 |
| 2026-02-20 12:00 |
17:52:58.49 |
-15:28:51.5 |
HIP 87574 |
12.56 |
| 2026-02-21 00:00 |
17:53:02.07 |
-15:28:36.8 |
HIP 87574 |
12.33 |
| 2026-02-21 12:00 |
17:53:05.60 |
-15:28:22.0 |
HIP 87574 |
12.17 |
| 2026-02-22 00:00 |
17:53:09.07 |
-15:28:07.1 |
HIP 87574 |
12.07 |
| 2026-02-22 12:00 |
17:53:12.50 |
-15:27:52.1 |
HIP 87574 |
12.05 |
| 2026-02-23 00:00 |
17:53:15.87 |
-15:27:37.1 |
HIP 87574 |
12.09 |
| 2026-02-23 12:00 |
17:53:19.19 |
-15:27:21.9 |
HIP 87574 |
12.19 |
| 2026-02-24 00:00 |
17:53:22.46 |
-15:27:06.7 |
HIP 87574 |
12.35 |