メタデータ
| 項目 |
値 |
| Designation |
66P/du Toit |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2018-05-20T11:15:17.081280Z |
| Orbit solution date (soln_date, UTC) |
2019-06-03T14:53:20Z |
| Obs used |
547 |
| NEO |
Yes |
| M1 |
15.700 |
| K1 |
7.000 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2014-10-31.0000000 |
| e |
0.78656817 |
| q (au) |
1.285451 |
| a (au) |
6.022773 |
| i (deg) |
18.668971 |
| Ω (om, deg) |
21.999851 |
| ω (w, deg) |
257.342734 |
| M (ma, deg) |
273.482032 |
等級
散乱 + 全体線形
$$
M_a = (13.128 + 5.614\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
13.128 |
| n |
5.614 |
| gf |
0.972 |
| gb |
-0.780 |
| k |
0.995 |
| δ90 |
9.986 |
| 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 |
| 2018-01-14 |
2018-05-20 |
+20.2696 |
-4.971 |
| 2018-05-21 |
2018-10-04 |
+19.3494 |
-5.821 |
| 2018-10-04 |
2018-11-10 |
-27.9509 |
+9.461 |
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 |
06:24:55.32 |
+41:42:59.0 |
HIP 30482 |
7.86 |
| 2026-03-26 12:00 |
06:24:57.00 |
+41:42:08.3 |
HIP 30482 |
8.71 |
| 2026-03-27 00:00 |
06:24:58.80 |
+41:41:17.5 |
HIP 30482 |
9.59 |
| 2026-03-27 12:00 |
06:25:00.72 |
+41:40:26.8 |
HIP 30482 |
10.49 |
| 2026-03-28 00:00 |
06:25:02.77 |
+41:39:36.0 |
HIP 30482 |
11.40 |
| 2026-03-28 12:00 |
06:25:04.94 |
+41:38:45.3 |
HIP 30482 |
12.32 |
| 2026-03-29 00:00 |
06:25:07.23 |
+41:37:54.7 |
HIP 30482 |
13.26 |
| 2026-03-29 12:00 |
06:25:09.64 |
+41:37:04.0 |
HIP 30482 |
14.22 |
| 2026-03-30 00:00 |
06:25:12.17 |
+41:36:13.4 |
HIP 30482 |
15.18 |
| 2026-03-30 12:00 |
06:25:14.82 |
+41:35:22.8 |
HIP 30482 |
16.16 |
| 2026-03-31 00:00 |
06:25:17.59 |
+41:34:32.3 |
HIP 30482 |
17.15 |
| 2026-03-31 12:00 |
06:25:20.48 |
+41:33:41.8 |
HIP 30482 |
18.15 |
| 2026-04-01 00:00 |
06:25:23.49 |
+41:32:51.4 |
HIP 30482 |
19.16 |
| 2026-04-01 12:00 |
06:25:26.62 |
+41:32:01.0 |
HIP 30482 |
20.18 |
| 2026-04-02 00:00 |
06:25:29.86 |
+41:31:10.7 |
HIP 30482 |
21.22 |
| 2026-04-02 12:00 |
06:25:33.22 |
+41:30:20.4 |
HIP 30482 |
22.26 |
| 2026-04-03 00:00 |
06:25:36.70 |
+41:29:30.2 |
HIP 30482 |
23.32 |
| 2026-04-03 12:00 |
06:25:40.30 |
+41:28:40.0 |
HIP 30482 |
24.39 |
| 2026-04-04 00:00 |
06:25:44.01 |
+41:27:49.9 |
HIP 30482 |
25.47 |
| 2026-04-04 12:00 |
06:25:47.83 |
+41:26:59.9 |
HIP 30482 |
26.56 |
| 2026-04-05 00:00 |
06:25:51.78 |
+41:26:09.9 |
HIP 30482 |
27.66 |
| 2026-04-05 12:00 |
06:25:55.83 |
+41:25:20.0 |
HIP 30482 |
28.78 |
| 2026-04-06 00:00 |
06:26:00.00 |
+41:24:30.2 |
HIP 30482 |
29.91 |
| 2026-04-06 12:00 |
06:26:04.28 |
+41:23:40.4 |
HIP 30810 |
29.86 |
| 2026-04-07 00:00 |
06:26:08.68 |
+41:22:50.8 |
HIP 30810 |
29.54 |
| 2026-04-07 12:00 |
06:26:13.19 |
+41:22:01.2 |
HIP 30810 |
29.24 |
| 2026-04-08 00:00 |
06:26:17.81 |
+41:21:11.7 |
HIP 30810 |
28.97 |
| 2026-04-08 12:00 |
06:26:22.54 |
+41:20:22.3 |
HIP 30810 |
28.72 |
| 2026-04-09 00:00 |
06:26:27.39 |
+41:19:32.9 |
HIP 30810 |
28.51 |
| 2026-04-09 12:00 |
06:26:32.34 |
+41:18:43.7 |
HIP 30877 |
27.64 |
| 2026-04-10 00:00 |
06:26:37.41 |
+41:17:54.5 |
HIP 30877 |
26.52 |
| 2026-04-10 12:00 |
06:26:42.58 |
+41:17:05.5 |
HIP 30877 |
25.39 |
| 2026-04-11 00:00 |
06:26:47.87 |
+41:16:16.5 |
HIP 30877 |
24.26 |
| 2026-04-11 12:00 |
06:26:53.26 |
+41:15:27.7 |
HIP 30877 |
23.12 |
| 2026-04-12 00:00 |
06:26:58.76 |
+41:14:38.9 |
HIP 30877 |
21.97 |
| 2026-04-12 12:00 |
06:27:04.37 |
+41:13:50.3 |
HIP 30877 |
20.83 |
| 2026-04-13 00:00 |
06:27:10.09 |
+41:13:01.7 |
HIP 30877 |
19.69 |
| 2026-04-13 12:00 |
06:27:15.91 |
+41:12:13.3 |
HIP 30877 |
18.56 |
| 2026-04-14 00:00 |
06:27:21.84 |
+41:11:24.9 |
HIP 30877 |
17.45 |
| 2026-04-14 12:00 |
06:27:27.88 |
+41:10:36.7 |
HIP 30877 |
16.35 |
| 2026-04-15 00:00 |
06:27:34.02 |
+41:09:48.6 |
HIP 30877 |
15.27 |
| 2026-04-15 12:00 |
06:27:40.26 |
+41:09:00.6 |
HIP 30877 |
14.24 |
| 2026-04-16 00:00 |
06:27:46.61 |
+41:08:12.8 |
HIP 30877 |
13.25 |