メタデータ
| 項目 |
値 |
| Designation |
C/2012 L2 (LINEAR) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2013-05-09T08:04:55.027200Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:14Z |
| Obs used |
2119 |
| NEO |
- |
| M1 |
11.300 |
| K1 |
6.250 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2012-12-18.0000000 |
| e |
0.99733350 |
| q (au) |
1.508545 |
| a (au) |
565.739557 |
| i (deg) |
70.980594 |
| Ω (om, deg) |
270.302116 |
| ω (w, deg) |
205.786395 |
| M (ma, deg) |
359.989575 |
等級
散乱 + 全体線形
$$
M_a = (11.171 + 4.614\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
11.171 |
| n |
4.614 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.874 |
| 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 |
| 2003-04-13 |
2012-06-17 |
-24.5614 |
+15.420 |
| 2012-06-17 |
2012-12-17 |
-0.8759 |
+0.427 |
| 2012-12-17 |
2013-05-09 |
+6.2793 |
-2.140 |
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 |
17:56:34.03 |
-23:17:11.6 |
HIP 87893 |
12.30 |
| 2026-07-29 12:00 |
17:56:30.64 |
-23:17:08.0 |
HIP 87893 |
12.84 |
| 2026-07-30 00:00 |
17:56:27.27 |
-23:17:04.4 |
HIP 87774 |
12.60 |
| 2026-07-30 12:00 |
17:56:23.93 |
-23:17:00.9 |
HIP 87774 |
12.05 |
| 2026-07-31 00:00 |
17:56:20.61 |
-23:16:57.3 |
HIP 87774 |
11.53 |
| 2026-07-31 12:00 |
17:56:17.32 |
-23:16:53.7 |
HIP 87774 |
11.03 |
| 2026-08-01 00:00 |
17:56:14.05 |
-23:16:50.2 |
HIP 87774 |
10.57 |
| 2026-08-01 12:00 |
17:56:10.81 |
-23:16:46.6 |
HIP 87774 |
10.15 |
| 2026-08-02 00:00 |
17:56:07.59 |
-23:16:43.0 |
HIP 87774 |
9.77 |
| 2026-08-02 12:00 |
17:56:04.39 |
-23:16:39.5 |
HIP 87774 |
9.44 |
| 2026-08-03 00:00 |
17:56:01.23 |
-23:16:35.9 |
HIP 87774 |
9.15 |
| 2026-08-03 12:00 |
17:55:58.08 |
-23:16:32.3 |
HIP 87774 |
8.92 |
| 2026-08-04 00:00 |
17:55:54.97 |
-23:16:28.8 |
HIP 87774 |
8.74 |
| 2026-08-04 12:00 |
17:55:51.88 |
-23:16:25.2 |
HIP 87774 |
8.62 |
| 2026-08-05 00:00 |
17:55:48.82 |
-23:16:21.7 |
HIP 87774 |
8.56 |
| 2026-08-05 12:00 |
17:55:45.78 |
-23:16:18.1 |
HIP 87774 |
8.55 |
| 2026-08-06 00:00 |
17:55:42.77 |
-23:16:14.6 |
HIP 87774 |
8.60 |
| 2026-08-06 12:00 |
17:55:39.79 |
-23:16:11.0 |
HIP 87774 |
8.70 |
| 2026-08-07 00:00 |
17:55:36.84 |
-23:16:07.5 |
HIP 87774 |
8.85 |
| 2026-08-07 12:00 |
17:55:33.91 |
-23:16:03.9 |
HIP 87774 |
9.05 |
| 2026-08-08 00:00 |
17:55:31.01 |
-23:16:00.4 |
HIP 87774 |
9.29 |
| 2026-08-08 12:00 |
17:55:28.14 |
-23:15:56.8 |
HIP 87774 |
9.57 |
| 2026-08-09 00:00 |
17:55:25.30 |
-23:15:53.3 |
HIP 87774 |
9.88 |
| 2026-08-09 12:00 |
17:55:22.49 |
-23:15:49.8 |
HIP 87774 |
10.22 |
| 2026-08-10 00:00 |
17:55:19.71 |
-23:15:46.2 |
HIP 87774 |
10.59 |
| 2026-08-10 12:00 |
17:55:16.95 |
-23:15:42.7 |
HIP 87774 |
10.97 |
| 2026-08-11 00:00 |
17:55:14.23 |
-23:15:39.2 |
HIP 87668 |
11.15 |
| 2026-08-11 12:00 |
17:55:11.53 |
-23:15:35.7 |
HIP 87668 |
10.53 |
| 2026-08-12 00:00 |
17:55:08.87 |
-23:15:32.2 |
HIP 87668 |
9.91 |
| 2026-08-12 12:00 |
17:55:06.23 |
-23:15:28.6 |
HIP 87668 |
9.31 |
| 2026-08-13 00:00 |
17:55:03.63 |
-23:15:25.1 |
HIP 87668 |
8.70 |
| 2026-08-13 12:00 |
17:55:01.06 |
-23:15:21.6 |
HIP 87668 |
8.11 |
| 2026-08-14 00:00 |
17:54:58.51 |
-23:15:18.1 |
HIP 87668 |
7.52 |
| 2026-08-14 12:00 |
17:54:56.00 |
-23:15:14.6 |
HIP 87668 |
6.95 |
| 2026-08-15 00:00 |
17:54:53.52 |
-23:15:11.2 |
HIP 87668 |
6.37 |
| 2026-08-15 12:00 |
17:54:51.07 |
-23:15:07.7 |
HIP 87668 |
5.81 |
| 2026-08-16 00:00 |
17:54:48.65 |
-23:15:04.2 |
HIP 87668 |
5.25 |
| 2026-08-16 12:00 |
17:54:46.26 |
-23:15:00.7 |
HIP 87668 |
4.70 |
| 2026-08-17 00:00 |
17:54:43.91 |
-23:14:57.2 |
HIP 87668 |
4.16 |
| 2026-08-17 12:00 |
17:54:41.58 |
-23:14:53.8 |
HIP 87668 |
3.62 |
| 2026-08-18 00:00 |
17:54:39.29 |
-23:14:50.3 |
HIP 87668 |
3.10 |
| 2026-08-18 12:00 |
17:54:37.03 |
-23:14:46.8 |
HIP 87668 |
2.58 |
| 2026-08-19 00:00 |
17:54:34.81 |
-23:14:43.4 |
HIP 87668 |
2.07 |