メタデータ
| 項目 |
値 |
| Designation |
C/2013 G9 (Tenagra) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2015-01-14T14:39:54.149760Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:34Z |
| Obs used |
496 |
| NEO |
- |
| M1 |
6.500 |
| 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) |
2014-06-28.0000000 |
| e |
1.00127209 |
| q (au) |
5.337621 |
| a (au) |
-4195.948868 |
| i (deg) |
146.233595 |
| Ω (om, deg) |
35.688660 |
| ω (w, deg) |
204.930440 |
| M (ma, deg) |
-0.000727 |
等級
散乱 + 全体線形
$$
M_a = (1.736 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
1.736 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.953 |
| 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 |
| 2013-04-09 |
2015-01-12 |
+0.8615 |
-0.712 |
| 2015-01-17 |
2016-04-06 |
+15.2777 |
-11.324 |
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 |
04:20:33.62 |
+05:07:32.9 |
HIP 20361 |
22.51 |
| 2026-07-29 12:00 |
04:20:35.35 |
+05:07:24.6 |
HIP 20361 |
22.31 |
| 2026-07-30 00:00 |
04:20:37.04 |
+05:07:16.2 |
HIP 20361 |
22.12 |
| 2026-07-30 12:00 |
04:20:38.70 |
+05:07:07.6 |
HIP 20361 |
21.94 |
| 2026-07-31 00:00 |
04:20:40.33 |
+05:06:58.9 |
HIP 20361 |
21.78 |
| 2026-07-31 12:00 |
04:20:41.93 |
+05:06:49.9 |
HIP 20361 |
21.63 |
| 2026-08-01 00:00 |
04:20:43.49 |
+05:06:40.8 |
HIP 20361 |
21.50 |
| 2026-08-01 12:00 |
04:20:45.02 |
+05:06:31.6 |
HIP 20361 |
21.38 |
| 2026-08-02 00:00 |
04:20:46.51 |
+05:06:22.1 |
HIP 20361 |
21.28 |
| 2026-08-02 12:00 |
04:20:47.97 |
+05:06:12.5 |
HIP 20361 |
21.19 |
| 2026-08-03 00:00 |
04:20:49.39 |
+05:06:02.8 |
HIP 20361 |
21.12 |
| 2026-08-03 12:00 |
04:20:50.79 |
+05:05:52.9 |
HIP 20361 |
21.06 |
| 2026-08-04 00:00 |
04:20:52.14 |
+05:05:42.8 |
HIP 20361 |
21.02 |
| 2026-08-04 12:00 |
04:20:53.46 |
+05:05:32.5 |
HIP 20361 |
20.98 |
| 2026-08-05 00:00 |
04:20:54.75 |
+05:05:22.1 |
HIP 20361 |
20.96 |
| 2026-08-05 12:00 |
04:20:56.00 |
+05:05:11.5 |
HIP 20361 |
20.96 |
| 2026-08-06 00:00 |
04:20:57.22 |
+05:05:00.8 |
HIP 20361 |
20.97 |
| 2026-08-06 12:00 |
04:20:58.40 |
+05:04:49.8 |
HIP 20361 |
20.98 |
| 2026-08-07 00:00 |
04:20:59.55 |
+05:04:38.8 |
HIP 20361 |
21.02 |
| 2026-08-07 12:00 |
04:21:00.66 |
+05:04:27.6 |
HIP 20361 |
21.06 |
| 2026-08-08 00:00 |
04:21:01.73 |
+05:04:16.2 |
HIP 20361 |
21.11 |
| 2026-08-08 12:00 |
04:21:02.77 |
+05:04:04.6 |
HIP 20361 |
21.18 |
| 2026-08-09 00:00 |
04:21:03.77 |
+05:03:52.9 |
HIP 20361 |
21.26 |
| 2026-08-09 12:00 |
04:21:04.74 |
+05:03:41.1 |
HIP 20361 |
21.34 |
| 2026-08-10 00:00 |
04:21:05.67 |
+05:03:29.0 |
HIP 20361 |
21.44 |
| 2026-08-10 12:00 |
04:21:06.56 |
+05:03:16.9 |
HIP 20361 |
21.55 |
| 2026-08-11 00:00 |
04:21:07.41 |
+05:03:04.6 |
HIP 20361 |
21.66 |
| 2026-08-11 12:00 |
04:21:08.23 |
+05:02:52.1 |
HIP 20361 |
21.79 |
| 2026-08-12 00:00 |
04:21:09.01 |
+05:02:39.5 |
HIP 20361 |
21.92 |
| 2026-08-12 12:00 |
04:21:09.76 |
+05:02:26.7 |
HIP 20361 |
22.06 |
| 2026-08-13 00:00 |
04:21:10.46 |
+05:02:13.7 |
HIP 20361 |
22.21 |
| 2026-08-13 12:00 |
04:21:11.13 |
+05:02:00.7 |
HIP 20361 |
22.37 |
| 2026-08-14 00:00 |
04:21:11.76 |
+05:01:47.4 |
HIP 20361 |
22.53 |
| 2026-08-14 12:00 |
04:21:12.35 |
+05:01:34.1 |
HIP 20361 |
22.70 |
| 2026-08-15 00:00 |
04:21:12.90 |
+05:01:20.6 |
HIP 20361 |
22.88 |
| 2026-08-15 12:00 |
04:21:13.42 |
+05:01:06.9 |
HIP 20361 |
23.07 |
| 2026-08-16 00:00 |
04:21:13.90 |
+05:00:53.1 |
HIP 20361 |
23.26 |
| 2026-08-16 12:00 |
04:21:14.33 |
+05:00:39.1 |
HIP 20361 |
23.45 |
| 2026-08-17 00:00 |
04:21:14.73 |
+05:00:25.1 |
HIP 20361 |
23.66 |
| 2026-08-17 12:00 |
04:21:15.10 |
+05:00:10.8 |
HIP 20361 |
23.86 |
| 2026-08-18 00:00 |
04:21:15.42 |
+04:59:56.5 |
HIP 20361 |
24.08 |
| 2026-08-18 12:00 |
04:21:15.70 |
+04:59:42.0 |
HIP 20361 |
24.30 |
| 2026-08-19 00:00 |
04:21:15.95 |
+04:59:27.3 |
HIP 20361 |
24.52 |