メタデータ
| 項目 |
値 |
| Designation |
C/1998 Y1 (LINEAR) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1998-11-21T13:57:33.661440Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:57Z |
| Obs used |
131 |
| NEO |
- |
| M1 |
14.000 |
| K1 |
10.000 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
1999-01-13.0000000 |
| e |
0.92389938 |
| q (au) |
1.746990 |
| a (au) |
22.956311 |
| i (deg) |
28.108156 |
| Ω (om, deg) |
98.858723 |
| ω (w, deg) |
339.843627 |
| M (ma, deg) |
0.469715 |
等級
散乱 + 全体線形
$$
M_a = (13.201 + 5.443\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
13.201 |
| n |
5.443 |
| gf |
0.906 |
| gb |
-0.901 |
| k |
1.000 |
| δ90 |
5.356 |
| 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 |
16:41:48.41 |
-08:00:16.0 |
HIP 81744 |
5.76 |
| 2026-07-29 12:00 |
16:41:46.68 |
-08:00:23.3 |
HIP 81744 |
5.90 |
| 2026-07-30 00:00 |
16:41:44.97 |
-08:00:30.7 |
HIP 81744 |
6.07 |
| 2026-07-30 12:00 |
16:41:43.28 |
-08:00:38.2 |
HIP 81744 |
6.27 |
| 2026-07-31 00:00 |
16:41:41.62 |
-08:00:45.7 |
HIP 81744 |
6.49 |
| 2026-07-31 12:00 |
16:41:39.98 |
-08:00:53.4 |
HIP 81744 |
6.73 |
| 2026-08-01 00:00 |
16:41:38.36 |
-08:01:01.1 |
HIP 81744 |
6.99 |
| 2026-08-01 12:00 |
16:41:36.76 |
-08:01:09.0 |
HIP 81744 |
7.26 |
| 2026-08-02 00:00 |
16:41:35.19 |
-08:01:17.0 |
HIP 81744 |
7.55 |
| 2026-08-02 12:00 |
16:41:33.64 |
-08:01:25.0 |
HIP 81744 |
7.84 |
| 2026-08-03 00:00 |
16:41:32.12 |
-08:01:33.1 |
HIP 81744 |
8.14 |
| 2026-08-03 12:00 |
16:41:30.62 |
-08:01:41.4 |
HIP 81744 |
8.45 |
| 2026-08-04 00:00 |
16:41:29.14 |
-08:01:49.7 |
HIP 81744 |
8.77 |
| 2026-08-04 12:00 |
16:41:27.69 |
-08:01:58.1 |
HIP 81744 |
9.08 |
| 2026-08-05 00:00 |
16:41:26.26 |
-08:02:06.6 |
HIP 81744 |
9.40 |
| 2026-08-05 12:00 |
16:41:24.85 |
-08:02:15.2 |
HIP 81744 |
9.73 |
| 2026-08-06 00:00 |
16:41:23.47 |
-08:02:23.9 |
HIP 81744 |
10.05 |
| 2026-08-06 12:00 |
16:41:22.12 |
-08:02:32.7 |
HIP 81744 |
10.38 |
| 2026-08-07 00:00 |
16:41:20.78 |
-08:02:41.6 |
HIP 81744 |
10.70 |
| 2026-08-07 12:00 |
16:41:19.48 |
-08:02:50.5 |
HIP 81744 |
11.02 |
| 2026-08-08 00:00 |
16:41:18.19 |
-08:02:59.6 |
HIP 81744 |
11.35 |
| 2026-08-08 12:00 |
16:41:16.93 |
-08:03:08.7 |
HIP 81744 |
11.67 |
| 2026-08-09 00:00 |
16:41:15.70 |
-08:03:17.9 |
HIP 81744 |
11.99 |
| 2026-08-09 12:00 |
16:41:14.49 |
-08:03:27.3 |
HIP 81744 |
12.31 |
| 2026-08-10 00:00 |
16:41:13.31 |
-08:03:36.7 |
HIP 81744 |
12.62 |
| 2026-08-10 12:00 |
16:41:12.15 |
-08:03:46.1 |
HIP 81744 |
12.93 |
| 2026-08-11 00:00 |
16:41:11.02 |
-08:03:55.7 |
HIP 81744 |
13.24 |
| 2026-08-11 12:00 |
16:41:09.91 |
-08:04:05.4 |
HIP 81744 |
13.55 |
| 2026-08-12 00:00 |
16:41:08.83 |
-08:04:15.1 |
HIP 81744 |
13.86 |
| 2026-08-12 12:00 |
16:41:07.78 |
-08:04:24.9 |
HIP 81744 |
14.16 |
| 2026-08-13 00:00 |
16:41:06.75 |
-08:04:34.8 |
HIP 81663 |
14.23 |
| 2026-08-13 12:00 |
16:41:05.74 |
-08:04:44.8 |
HIP 81663 |
14.02 |
| 2026-08-14 00:00 |
16:41:04.76 |
-08:04:54.9 |
HIP 81663 |
13.82 |
| 2026-08-14 12:00 |
16:41:03.81 |
-08:05:05.1 |
HIP 81663 |
13.62 |
| 2026-08-15 00:00 |
16:41:02.89 |
-08:05:15.3 |
HIP 81663 |
13.42 |
| 2026-08-15 12:00 |
16:41:01.99 |
-08:05:25.6 |
HIP 81663 |
13.22 |
| 2026-08-16 00:00 |
16:41:01.11 |
-08:05:36.0 |
HIP 81663 |
13.03 |
| 2026-08-16 12:00 |
16:41:00.26 |
-08:05:46.4 |
HIP 81663 |
12.84 |
| 2026-08-17 00:00 |
16:40:59.44 |
-08:05:57.0 |
HIP 81663 |
12.65 |
| 2026-08-17 12:00 |
16:40:58.65 |
-08:06:07.6 |
HIP 81663 |
12.46 |
| 2026-08-18 00:00 |
16:40:57.88 |
-08:06:18.3 |
HIP 81663 |
12.28 |
| 2026-08-18 12:00 |
16:40:57.13 |
-08:06:29.0 |
HIP 81663 |
12.09 |
| 2026-08-19 00:00 |
16:40:56.42 |
-08:06:39.9 |
HIP 81663 |
11.91 |