メタデータ
| 項目 |
値 |
| Designation |
C/1998 U5 (LINEAR) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1998-12-21T18:14:25.114560Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:57Z |
| Obs used |
406 |
| NEO |
- |
| M1 |
11.000 |
| K1 |
15.500 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
1998-12-01.0000000 |
| e |
0.98797943 |
| q (au) |
1.236453 |
| a (au) |
102.861449 |
| i (deg) |
131.764750 |
| Ω (om, deg) |
66.650605 |
| ω (w, deg) |
51.134275 |
| M (ma, deg) |
359.980387 |
等級
散乱 + 全体線形
$$
M_a = (8.137 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
8.137 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.500 |
| k |
1.000 |
| 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 |
| 1998-10-30 |
1998-12-21 |
+23.4645 |
-2.542 |
| 1998-12-21 |
1999-05-11 |
-3.5652 |
+0.381 |
| 1999-05-11 |
1999-12-09 |
-44.9953 |
+16.194 |
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 |
14:01:56.95 |
-39:45:44.5 |
HIP 68499 |
8.74 |
| 2026-03-26 12:00 |
14:01:54.10 |
-39:45:43.0 |
HIP 68499 |
8.31 |
| 2026-03-27 00:00 |
14:01:51.23 |
-39:45:41.2 |
HIP 68499 |
7.88 |
| 2026-03-27 12:00 |
14:01:48.35 |
-39:45:39.3 |
HIP 68499 |
7.47 |
| 2026-03-28 00:00 |
14:01:45.46 |
-39:45:37.3 |
HIP 68499 |
7.08 |
| 2026-03-28 12:00 |
14:01:42.56 |
-39:45:35.0 |
HIP 68499 |
6.71 |
| 2026-03-29 00:00 |
14:01:39.64 |
-39:45:32.5 |
HIP 68499 |
6.35 |
| 2026-03-29 12:00 |
14:01:36.71 |
-39:45:29.9 |
HIP 68499 |
6.03 |
| 2026-03-30 00:00 |
14:01:33.77 |
-39:45:27.1 |
HIP 68499 |
5.74 |
| 2026-03-30 12:00 |
14:01:30.83 |
-39:45:24.1 |
HIP 68499 |
5.49 |
| 2026-03-31 00:00 |
14:01:27.87 |
-39:45:20.9 |
HIP 68499 |
5.29 |
| 2026-03-31 12:00 |
14:01:24.90 |
-39:45:17.5 |
HIP 68499 |
5.14 |
| 2026-04-01 00:00 |
14:01:21.92 |
-39:45:14.0 |
HIP 68499 |
5.05 |
| 2026-04-01 12:00 |
14:01:18.92 |
-39:45:10.2 |
HIP 68499 |
5.02 |
| 2026-04-02 00:00 |
14:01:15.92 |
-39:45:06.3 |
HIP 68499 |
5.05 |
| 2026-04-02 12:00 |
14:01:12.91 |
-39:45:02.2 |
HIP 68499 |
5.15 |
| 2026-04-03 00:00 |
14:01:09.89 |
-39:44:57.9 |
HIP 68499 |
5.31 |
| 2026-04-03 12:00 |
14:01:06.87 |
-39:44:53.5 |
HIP 68499 |
5.52 |
| 2026-04-04 00:00 |
14:01:03.83 |
-39:44:48.8 |
HIP 68499 |
5.79 |
| 2026-04-04 12:00 |
14:01:00.78 |
-39:44:44.0 |
HIP 68499 |
6.10 |
| 2026-04-05 00:00 |
14:00:57.73 |
-39:44:39.0 |
HIP 68499 |
6.44 |
| 2026-04-05 12:00 |
14:00:54.66 |
-39:44:33.8 |
HIP 68499 |
6.82 |
| 2026-04-06 00:00 |
14:00:51.59 |
-39:44:28.4 |
HIP 68499 |
7.23 |
| 2026-04-06 12:00 |
14:00:48.51 |
-39:44:22.9 |
HIP 68499 |
7.67 |
| 2026-04-07 00:00 |
14:00:45.43 |
-39:44:17.2 |
HIP 68499 |
8.12 |
| 2026-04-07 12:00 |
14:00:42.33 |
-39:44:11.3 |
HIP 68499 |
8.60 |
| 2026-04-08 00:00 |
14:00:39.23 |
-39:44:05.2 |
HIP 68499 |
9.08 |
| 2026-04-08 12:00 |
14:00:36.12 |
-39:43:59.0 |
HIP 68499 |
9.58 |
| 2026-04-09 00:00 |
14:00:33.01 |
-39:43:52.5 |
HIP 68499 |
10.10 |
| 2026-04-09 12:00 |
14:00:29.89 |
-39:43:45.9 |
HIP 68499 |
10.62 |
| 2026-04-10 00:00 |
14:00:26.76 |
-39:43:39.1 |
HIP 68499 |
11.15 |
| 2026-04-10 12:00 |
14:00:23.63 |
-39:43:32.2 |
HIP 68499 |
11.69 |
| 2026-04-11 00:00 |
14:00:20.49 |
-39:43:25.0 |
HIP 68499 |
12.24 |
| 2026-04-11 12:00 |
14:00:17.35 |
-39:43:17.7 |
HIP 68499 |
12.80 |
| 2026-04-12 00:00 |
14:00:14.20 |
-39:43:10.3 |
HIP 68499 |
13.36 |
| 2026-04-12 12:00 |
14:00:11.04 |
-39:43:02.6 |
HIP 68499 |
13.92 |
| 2026-04-13 00:00 |
14:00:07.88 |
-39:42:54.8 |
HIP 68499 |
14.49 |
| 2026-04-13 12:00 |
14:00:04.72 |
-39:42:46.8 |
HIP 68499 |
15.07 |
| 2026-04-14 00:00 |
14:00:01.55 |
-39:42:38.6 |
HIP 68499 |
15.65 |
| 2026-04-14 12:00 |
13:59:58.38 |
-39:42:30.3 |
HIP 68499 |
16.23 |
| 2026-04-15 00:00 |
13:59:55.20 |
-39:42:21.7 |
HIP 68499 |
16.82 |
| 2026-04-15 12:00 |
13:59:52.02 |
-39:42:13.1 |
HIP 68499 |
17.41 |
| 2026-04-16 00:00 |
13:59:48.84 |
-39:42:04.2 |
HIP 68499 |
18.00 |