メタデータ
| 項目 |
値 |
| Designation |
C/1999 A1 (Tilbrook) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1999-01-29T15:46:41.666880Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:57Z |
| Obs used |
68 |
| NEO |
- |
| M1 |
14.300 |
| K1 |
10.000 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
1999-01-20.0000000 |
| e |
0.99589489 |
| q (au) |
0.730741 |
| a (au) |
178.007719 |
| i (deg) |
89.481788 |
| Ω (om, deg) |
259.123002 |
| ω (w, deg) |
232.669862 |
| M (ma, deg) |
359.995992 |
等級
散乱 + 全体線形
$$
M_a = (13.200 + 2.643\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
13.200 |
| n |
2.643 |
| gf |
0.800 |
| 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
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
17:29:18.31 |
+17:02:59.4 |
HIP 85458 |
22.13 |
| 2026-05-12 12:00 |
17:29:16.16 |
+17:03:14.1 |
HIP 85458 |
21.71 |
| 2026-05-13 00:00 |
17:29:14.01 |
+17:03:28.8 |
HIP 85458 |
21.29 |
| 2026-05-13 12:00 |
17:29:11.84 |
+17:03:43.2 |
HIP 85458 |
20.87 |
| 2026-05-14 00:00 |
17:29:09.66 |
+17:03:57.5 |
HIP 85458 |
20.46 |
| 2026-05-14 12:00 |
17:29:07.48 |
+17:04:11.6 |
HIP 85458 |
20.05 |
| 2026-05-15 00:00 |
17:29:05.28 |
+17:04:25.6 |
HIP 85458 |
19.65 |
| 2026-05-15 12:00 |
17:29:03.07 |
+17:04:39.3 |
HIP 85458 |
19.25 |
| 2026-05-16 00:00 |
17:29:00.84 |
+17:04:52.9 |
HIP 85458 |
18.86 |
| 2026-05-16 12:00 |
17:28:58.61 |
+17:05:06.4 |
HIP 85458 |
18.48 |
| 2026-05-17 00:00 |
17:28:56.37 |
+17:05:19.6 |
HIP 85458 |
18.10 |
| 2026-05-17 12:00 |
17:28:54.12 |
+17:05:32.7 |
HIP 85458 |
17.72 |
| 2026-05-18 00:00 |
17:28:51.86 |
+17:05:45.6 |
HIP 85458 |
17.36 |
| 2026-05-18 12:00 |
17:28:49.59 |
+17:05:58.3 |
HIP 85458 |
17.01 |
| 2026-05-19 00:00 |
17:28:47.30 |
+17:06:10.9 |
HIP 85458 |
16.66 |
| 2026-05-19 12:00 |
17:28:45.01 |
+17:06:23.3 |
HIP 85458 |
16.32 |
| 2026-05-20 00:00 |
17:28:42.71 |
+17:06:35.5 |
HIP 85458 |
16.00 |
| 2026-05-20 12:00 |
17:28:40.41 |
+17:06:47.5 |
HIP 85458 |
15.68 |
| 2026-05-21 00:00 |
17:28:38.09 |
+17:06:59.3 |
HIP 85458 |
15.38 |
| 2026-05-21 12:00 |
17:28:35.76 |
+17:07:10.9 |
HIP 85458 |
15.10 |
| 2026-05-22 00:00 |
17:28:33.43 |
+17:07:22.4 |
HIP 85458 |
14.82 |
| 2026-05-22 12:00 |
17:28:31.09 |
+17:07:33.7 |
HIP 85458 |
14.56 |
| 2026-05-23 00:00 |
17:28:28.74 |
+17:07:44.8 |
HIP 85458 |
14.32 |
| 2026-05-23 12:00 |
17:28:26.38 |
+17:07:55.7 |
HIP 85458 |
14.10 |
| 2026-05-24 00:00 |
17:28:24.01 |
+17:08:06.4 |
HIP 85458 |
13.89 |
| 2026-05-24 12:00 |
17:28:21.64 |
+17:08:17.0 |
HIP 85458 |
13.70 |
| 2026-05-25 00:00 |
17:28:19.26 |
+17:08:27.3 |
HIP 85458 |
13.54 |
| 2026-05-25 12:00 |
17:28:16.87 |
+17:08:37.5 |
HIP 85458 |
13.39 |
| 2026-05-26 00:00 |
17:28:14.47 |
+17:08:47.5 |
HIP 85458 |
13.26 |
| 2026-05-26 12:00 |
17:28:12.07 |
+17:08:57.3 |
HIP 85458 |
13.16 |
| 2026-05-27 00:00 |
17:28:09.66 |
+17:09:06.9 |
HIP 85458 |
13.08 |
| 2026-05-27 12:00 |
17:28:07.25 |
+17:09:16.3 |
HIP 85458 |
13.02 |
| 2026-05-28 00:00 |
17:28:04.83 |
+17:09:25.5 |
HIP 85458 |
12.99 |
| 2026-05-28 12:00 |
17:28:02.40 |
+17:09:34.6 |
HIP 85458 |
12.98 |
| 2026-05-29 00:00 |
17:27:59.97 |
+17:09:43.4 |
HIP 85458 |
13.00 |
| 2026-05-29 12:00 |
17:27:57.53 |
+17:09:52.1 |
HIP 85458 |
13.04 |
| 2026-05-30 00:00 |
17:27:55.09 |
+17:10:00.6 |
HIP 85458 |
13.10 |
| 2026-05-30 12:00 |
17:27:52.64 |
+17:10:08.8 |
HIP 85458 |
13.19 |
| 2026-05-31 00:00 |
17:27:50.19 |
+17:10:16.9 |
HIP 85458 |
13.30 |
| 2026-05-31 12:00 |
17:27:47.73 |
+17:10:24.8 |
HIP 85458 |
13.43 |
| 2026-06-01 00:00 |
17:27:45.26 |
+17:10:32.5 |
HIP 85458 |
13.59 |
| 2026-06-01 12:00 |
17:27:42.79 |
+17:10:40.0 |
HIP 85458 |
13.77 |
| 2026-06-02 00:00 |
17:27:40.32 |
+17:10:47.3 |
HIP 85458 |
13.97 |