メタデータ
| 項目 |
値 |
| Designation |
C/1998 G1 (LINEAR) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1998-11-16T14:59:02.595840Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:53Z |
| Obs used |
161 |
| NEO |
- |
| M1 |
13.800 |
| K1 |
4.500 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
1998-04-21.0000000 |
| e |
0.82369261 |
| q (au) |
2.133379 |
| a (au) |
12.100336 |
| i (deg) |
109.714727 |
| Ω (om, deg) |
341.383665 |
| ω (w, deg) |
236.322318 |
| M (ma, deg) |
355.091490 |
等級
散乱 + 全体線形
$$
M_a = (7.797 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
7.797 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.998 |
| 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 |
| 1998-04-02 |
1998-11-16 |
+14.8291 |
-7.029 |
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) |
| 2026-07-29 00:00 |
19:18:57.93 |
+41:08:47.2 |
HIP 94972 |
10.07 |
| 2026-07-29 12:00 |
19:18:49.97 |
+41:08:22.7 |
HIP 94972 |
11.40 |
| 2026-07-30 00:00 |
19:18:42.03 |
+41:07:57.6 |
HIP 94972 |
12.79 |
| 2026-07-30 12:00 |
19:18:34.12 |
+41:07:31.9 |
HIP 94972 |
14.22 |
| 2026-07-31 00:00 |
19:18:26.22 |
+41:07:05.5 |
HIP 94972 |
15.67 |
| 2026-07-31 12:00 |
19:18:18.35 |
+41:06:38.5 |
HIP 94780 |
16.00 |
| 2026-08-01 00:00 |
19:18:10.50 |
+41:06:10.8 |
HIP 94780 |
15.11 |
| 2026-08-01 12:00 |
19:18:02.68 |
+41:05:42.6 |
HIP 94780 |
14.34 |
| 2026-08-02 00:00 |
19:17:54.88 |
+41:05:13.6 |
HIP 94780 |
13.72 |
| 2026-08-02 12:00 |
19:17:47.11 |
+41:04:44.1 |
HIP 94780 |
13.26 |
| 2026-08-03 00:00 |
19:17:39.36 |
+41:04:13.9 |
HIP 94780 |
12.99 |
| 2026-08-03 12:00 |
19:17:31.64 |
+41:03:43.0 |
HIP 94780 |
12.90 |
| 2026-08-04 00:00 |
19:17:23.94 |
+41:03:11.6 |
HIP 94780 |
13.01 |
| 2026-08-04 12:00 |
19:17:16.28 |
+41:02:39.5 |
HIP 94780 |
13.30 |
| 2026-08-05 00:00 |
19:17:08.64 |
+41:02:06.8 |
HIP 94780 |
13.78 |
| 2026-08-05 12:00 |
19:17:01.03 |
+41:01:33.5 |
HIP 94780 |
14.41 |
| 2026-08-06 00:00 |
19:16:53.45 |
+41:00:59.6 |
HIP 94780 |
15.18 |
| 2026-08-06 12:00 |
19:16:45.90 |
+41:00:25.1 |
HIP 94780 |
16.07 |
| 2026-08-07 00:00 |
19:16:38.38 |
+40:59:49.9 |
HIP 94780 |
17.06 |
| 2026-08-07 12:00 |
19:16:30.89 |
+40:59:14.2 |
HIP 94780 |
18.13 |
| 2026-08-08 00:00 |
19:16:23.43 |
+40:58:37.8 |
HIP 94780 |
19.27 |
| 2026-08-08 12:00 |
19:16:16.01 |
+40:58:00.9 |
HIP 94780 |
20.47 |
| 2026-08-09 00:00 |
19:16:08.61 |
+40:57:23.3 |
HIP 94780 |
21.72 |
| 2026-08-09 12:00 |
19:16:01.25 |
+40:56:45.2 |
HIP 94780 |
23.00 |
| 2026-08-10 00:00 |
19:15:53.93 |
+40:56:06.4 |
HIP 94780 |
24.32 |
| 2026-08-10 12:00 |
19:15:46.64 |
+40:55:27.1 |
HIP 94780 |
25.66 |
| 2026-08-11 00:00 |
19:15:39.39 |
+40:54:47.2 |
HIP 94780 |
27.02 |
| 2026-08-11 12:00 |
19:15:32.17 |
+40:54:06.7 |
HIP 94780 |
28.41 |
| 2026-08-12 00:00 |
19:15:24.99 |
+40:53:25.6 |
HIP 94780 |
29.81 |
| 2026-08-12 12:00 |
19:15:17.84 |
+40:52:44.0 |
HIP 94780 |
31.22 |
| 2026-08-13 00:00 |
19:15:10.73 |
+40:52:01.8 |
HIP 94659 |
31.07 |
| 2026-08-13 12:00 |
19:15:03.66 |
+40:51:19.0 |
HIP 94659 |
30.67 |
| 2026-08-14 00:00 |
19:14:56.63 |
+40:50:35.6 |
HIP 94659 |
30.34 |
| 2026-08-14 12:00 |
19:14:49.64 |
+40:49:51.8 |
HIP 94659 |
30.07 |
| 2026-08-15 00:00 |
19:14:42.69 |
+40:49:07.3 |
HIP 94659 |
29.86 |
| 2026-08-15 12:00 |
19:14:35.78 |
+40:48:22.3 |
HIP 94659 |
29.72 |
| 2026-08-16 00:00 |
19:14:28.91 |
+40:47:36.8 |
HIP 94659 |
29.64 |
| 2026-08-16 12:00 |
19:14:22.09 |
+40:46:50.8 |
HIP 94659 |
29.63 |
| 2026-08-17 00:00 |
19:14:15.30 |
+40:46:04.2 |
HIP 94659 |
29.68 |
| 2026-08-17 12:00 |
19:14:08.56 |
+40:45:17.0 |
HIP 94659 |
29.79 |
| 2026-08-18 00:00 |
19:14:01.86 |
+40:44:29.4 |
HIP 94659 |
29.97 |
| 2026-08-18 12:00 |
19:13:55.20 |
+40:43:41.2 |
HIP 94659 |
30.22 |
| 2026-08-19 00:00 |
19:13:48.59 |
+40:42:52.6 |
HIP 94659 |
30.52 |