メタデータ
| 項目 |
値 |
| Designation |
C/1999 F2 (Dalcanton) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1998-08-23T16:33:57.314880Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:57Z |
| Obs used |
137 |
| NEO |
- |
| M1 |
7.800 |
| K1 |
7.750 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
1999-09-29.0000000 |
| e |
0.99821105 |
| q (au) |
4.718078 |
| a (au) |
2637.338054 |
| i (deg) |
56.427410 |
| Ω (om, deg) |
210.297746 |
| ω (w, deg) |
352.352637 |
| M (ma, deg) |
0.002920 |
等級
散乱 + 全体線形
$$
M_a = (5.004 + 5.237\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
5.004 |
| n |
5.237 |
| gf |
1.000 |
| gb |
-0.608 |
| 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
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
23:06:31.34 |
+33:47:36.9 |
HIP 113991 |
25.11 |
| 2026-07-29 12:00 |
23:06:29.39 |
+33:47:42.4 |
HIP 113991 |
24.76 |
| 2026-07-30 00:00 |
23:06:27.42 |
+33:47:47.7 |
HIP 113991 |
24.42 |
| 2026-07-30 12:00 |
23:06:25.44 |
+33:47:52.8 |
HIP 113991 |
24.07 |
| 2026-07-31 00:00 |
23:06:23.45 |
+33:47:57.6 |
HIP 113991 |
23.73 |
| 2026-07-31 12:00 |
23:06:21.43 |
+33:48:02.2 |
HIP 113991 |
23.39 |
| 2026-08-01 00:00 |
23:06:19.41 |
+33:48:06.7 |
HIP 113991 |
23.05 |
| 2026-08-01 12:00 |
23:06:17.37 |
+33:48:10.8 |
HIP 113991 |
22.72 |
| 2026-08-02 00:00 |
23:06:15.31 |
+33:48:14.8 |
HIP 113991 |
22.39 |
| 2026-08-02 12:00 |
23:06:13.24 |
+33:48:18.6 |
HIP 113991 |
22.07 |
| 2026-08-03 00:00 |
23:06:11.16 |
+33:48:22.1 |
HIP 113991 |
21.75 |
| 2026-08-03 12:00 |
23:06:09.07 |
+33:48:25.4 |
HIP 113991 |
21.44 |
| 2026-08-04 00:00 |
23:06:06.96 |
+33:48:28.5 |
HIP 113991 |
21.13 |
| 2026-08-04 12:00 |
23:06:04.83 |
+33:48:31.4 |
HIP 113991 |
20.83 |
| 2026-08-05 00:00 |
23:06:02.69 |
+33:48:34.1 |
HIP 113991 |
20.54 |
| 2026-08-05 12:00 |
23:06:00.54 |
+33:48:36.5 |
HIP 113991 |
20.25 |
| 2026-08-06 00:00 |
23:05:58.38 |
+33:48:38.7 |
HIP 113991 |
19.97 |
| 2026-08-06 12:00 |
23:05:56.20 |
+33:48:40.7 |
HIP 113991 |
19.70 |
| 2026-08-07 00:00 |
23:05:54.02 |
+33:48:42.5 |
HIP 113991 |
19.43 |
| 2026-08-07 12:00 |
23:05:51.81 |
+33:48:44.0 |
HIP 113991 |
19.18 |
| 2026-08-08 00:00 |
23:05:49.60 |
+33:48:45.3 |
HIP 113991 |
18.93 |
| 2026-08-08 12:00 |
23:05:47.37 |
+33:48:46.4 |
HIP 113991 |
18.70 |
| 2026-08-09 00:00 |
23:05:45.14 |
+33:48:47.3 |
HIP 113991 |
18.47 |
| 2026-08-09 12:00 |
23:05:42.88 |
+33:48:47.9 |
HIP 113991 |
18.26 |
| 2026-08-10 00:00 |
23:05:40.62 |
+33:48:48.4 |
HIP 113991 |
18.06 |
| 2026-08-10 12:00 |
23:05:38.35 |
+33:48:48.6 |
HIP 113991 |
17.87 |
| 2026-08-11 00:00 |
23:05:36.06 |
+33:48:48.5 |
HIP 113991 |
17.70 |
| 2026-08-11 12:00 |
23:05:33.77 |
+33:48:48.3 |
HIP 113991 |
17.54 |
| 2026-08-12 00:00 |
23:05:31.46 |
+33:48:47.8 |
HIP 113991 |
17.39 |
| 2026-08-12 12:00 |
23:05:29.14 |
+33:48:47.0 |
HIP 113991 |
17.26 |
| 2026-08-13 00:00 |
23:05:26.82 |
+33:48:46.1 |
HIP 113991 |
17.15 |
| 2026-08-13 12:00 |
23:05:24.48 |
+33:48:44.9 |
HIP 113991 |
17.05 |
| 2026-08-14 00:00 |
23:05:22.13 |
+33:48:43.5 |
HIP 113991 |
16.96 |
| 2026-08-14 12:00 |
23:05:19.77 |
+33:48:41.9 |
HIP 113991 |
16.90 |
| 2026-08-15 00:00 |
23:05:17.40 |
+33:48:40.0 |
HIP 113991 |
16.85 |
| 2026-08-15 12:00 |
23:05:15.02 |
+33:48:38.0 |
HIP 113991 |
16.82 |
| 2026-08-16 00:00 |
23:05:12.64 |
+33:48:35.6 |
HIP 113991 |
16.81 |
| 2026-08-16 12:00 |
23:05:10.24 |
+33:48:33.1 |
HIP 113991 |
16.81 |
| 2026-08-17 00:00 |
23:05:07.83 |
+33:48:30.3 |
HIP 113991 |
16.84 |
| 2026-08-17 12:00 |
23:05:05.42 |
+33:48:27.3 |
HIP 113991 |
16.88 |
| 2026-08-18 00:00 |
23:05:03.00 |
+33:48:24.1 |
HIP 113991 |
16.94 |
| 2026-08-18 12:00 |
23:05:00.57 |
+33:48:20.7 |
HIP 113991 |
17.02 |
| 2026-08-19 00:00 |
23:04:58.13 |
+33:48:17.0 |
HIP 113991 |
17.12 |