メタデータ
| 項目 |
値 |
| Designation |
C/1971 E1 (Toba) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1971-04-17T05:58:54.240960Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:19Z |
| Obs used |
137 |
| NEO |
- |
| M1 |
4.900 |
| K1 |
24.750 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
1971-05-08.0000000 |
| e |
1.00097756 |
| q (au) |
1.233346 |
| a (au) |
-1261.660970 |
| i (deg) |
109.684237 |
| Ω (om, deg) |
104.077477 |
| ω (w, deg) |
152.361820 |
| M (ma, deg) |
0.000456 |
等級
散乱 + 全体線形
$$
M_a = (5.808 + 5.913\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
5.808 |
| n |
5.913 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.984 |
| 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 |
| 1971-04-18 |
1971-06-28 |
+16.5114 |
-2.215 |
| 1971-06-28 |
1971-09-09 |
-10.7727 |
+3.319 |
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 |
07:40:18.91 |
-17:49:07.8 |
HIP 37313 |
10.27 |
| 2026-07-29 12:00 |
07:40:20.35 |
-17:49:13.1 |
HIP 37313 |
10.57 |
| 2026-07-30 00:00 |
07:40:21.78 |
-17:49:18.6 |
HIP 37313 |
10.87 |
| 2026-07-30 12:00 |
07:40:23.21 |
-17:49:24.2 |
HIP 37313 |
11.17 |
| 2026-07-31 00:00 |
07:40:24.64 |
-17:49:29.9 |
HIP 37313 |
11.48 |
| 2026-07-31 12:00 |
07:40:26.06 |
-17:49:35.7 |
HIP 37313 |
11.78 |
| 2026-08-01 00:00 |
07:40:27.48 |
-17:49:41.6 |
HIP 37313 |
12.09 |
| 2026-08-01 12:00 |
07:40:28.90 |
-17:49:47.6 |
HIP 37313 |
12.40 |
| 2026-08-02 00:00 |
07:40:30.31 |
-17:49:53.7 |
HIP 37313 |
12.71 |
| 2026-08-02 12:00 |
07:40:31.72 |
-17:49:59.9 |
HIP 37313 |
13.02 |
| 2026-08-03 00:00 |
07:40:33.13 |
-17:50:06.2 |
HIP 37313 |
13.33 |
| 2026-08-03 12:00 |
07:40:34.53 |
-17:50:12.6 |
HIP 37313 |
13.65 |
| 2026-08-04 00:00 |
07:40:35.93 |
-17:50:19.1 |
HIP 37313 |
13.96 |
| 2026-08-04 12:00 |
07:40:37.33 |
-17:50:25.7 |
HIP 37313 |
14.27 |
| 2026-08-05 00:00 |
07:40:38.72 |
-17:50:32.5 |
HIP 37313 |
14.59 |
| 2026-08-05 12:00 |
07:40:40.10 |
-17:50:39.3 |
HIP 37313 |
14.90 |
| 2026-08-06 00:00 |
07:40:41.49 |
-17:50:46.2 |
HIP 37313 |
15.22 |
| 2026-08-06 12:00 |
07:40:42.87 |
-17:50:53.2 |
HIP 37313 |
15.53 |
| 2026-08-07 00:00 |
07:40:44.24 |
-17:51:00.3 |
HIP 37313 |
15.85 |
| 2026-08-07 12:00 |
07:40:45.61 |
-17:51:07.6 |
HIP 37313 |
16.17 |
| 2026-08-08 00:00 |
07:40:46.98 |
-17:51:14.9 |
HIP 37313 |
16.48 |
| 2026-08-08 12:00 |
07:40:48.34 |
-17:51:22.3 |
HIP 37313 |
16.80 |
| 2026-08-09 00:00 |
07:40:49.70 |
-17:51:29.8 |
HIP 37313 |
17.11 |
| 2026-08-09 12:00 |
07:40:51.05 |
-17:51:37.4 |
HIP 37313 |
17.43 |
| 2026-08-10 00:00 |
07:40:52.40 |
-17:51:45.1 |
HIP 37313 |
17.75 |
| 2026-08-10 12:00 |
07:40:53.74 |
-17:51:52.9 |
HIP 37313 |
18.06 |
| 2026-08-11 00:00 |
07:40:55.08 |
-17:52:00.8 |
HIP 37313 |
18.38 |
| 2026-08-11 12:00 |
07:40:56.41 |
-17:52:08.8 |
HIP 37313 |
18.69 |
| 2026-08-12 00:00 |
07:40:57.74 |
-17:52:16.9 |
HIP 37313 |
19.01 |
| 2026-08-12 12:00 |
07:40:59.06 |
-17:52:25.1 |
HIP 37313 |
19.32 |
| 2026-08-13 00:00 |
07:41:00.38 |
-17:52:33.4 |
HIP 37313 |
19.64 |
| 2026-08-13 12:00 |
07:41:01.69 |
-17:52:41.7 |
HIP 37313 |
19.95 |
| 2026-08-14 00:00 |
07:41:02.99 |
-17:52:50.2 |
HIP 37313 |
20.26 |
| 2026-08-14 12:00 |
07:41:04.29 |
-17:52:58.8 |
HIP 37313 |
20.58 |
| 2026-08-15 00:00 |
07:41:05.58 |
-17:53:07.4 |
HIP 37313 |
20.89 |
| 2026-08-15 12:00 |
07:41:06.87 |
-17:53:16.1 |
HIP 37313 |
21.20 |
| 2026-08-16 00:00 |
07:41:08.15 |
-17:53:25.0 |
HIP 37313 |
21.51 |
| 2026-08-16 12:00 |
07:41:09.43 |
-17:53:33.9 |
HIP 37313 |
21.82 |
| 2026-08-17 00:00 |
07:41:10.70 |
-17:53:42.9 |
HIP 37313 |
22.13 |
| 2026-08-17 12:00 |
07:41:11.96 |
-17:53:52.0 |
HIP 37313 |
22.44 |
| 2026-08-18 00:00 |
07:41:13.21 |
-17:54:01.1 |
HIP 37526 |
22.62 |
| 2026-08-18 12:00 |
07:41:14.46 |
-17:54:10.4 |
HIP 37526 |
22.32 |
| 2026-08-19 00:00 |
07:41:15.71 |
-17:54:19.7 |
HIP 37526 |
22.03 |