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) |
| 2026-09-20 00:00 |
07:42:17.83 |
-18:06:42.3 |
HIP 37526 |
6.29 |
| 2026-09-20 12:00 |
07:42:18.47 |
-18:06:55.6 |
HIP 37526 |
6.15 |
| 2026-09-21 00:00 |
07:42:19.10 |
-18:07:08.9 |
HIP 37526 |
6.01 |
| 2026-09-21 12:00 |
07:42:19.73 |
-18:07:22.3 |
HIP 37526 |
5.88 |
| 2026-09-22 00:00 |
07:42:20.34 |
-18:07:35.7 |
HIP 37526 |
5.76 |
| 2026-09-22 12:00 |
07:42:20.94 |
-18:07:49.1 |
HIP 37526 |
5.65 |
| 2026-09-23 00:00 |
07:42:21.52 |
-18:08:02.5 |
HIP 37526 |
5.54 |
| 2026-09-23 12:00 |
07:42:22.10 |
-18:08:15.9 |
HIP 37526 |
5.45 |
| 2026-09-24 00:00 |
07:42:22.66 |
-18:08:29.4 |
HIP 37526 |
5.36 |
| 2026-09-24 12:00 |
07:42:23.22 |
-18:08:42.9 |
HIP 37526 |
5.28 |
| 2026-09-25 00:00 |
07:42:23.76 |
-18:08:56.5 |
HIP 37526 |
5.21 |
| 2026-09-25 12:00 |
07:42:24.29 |
-18:09:10.0 |
HIP 37526 |
5.15 |
| 2026-09-26 00:00 |
07:42:24.80 |
-18:09:23.6 |
HIP 37526 |
5.10 |
| 2026-09-26 12:00 |
07:42:25.31 |
-18:09:37.2 |
HIP 37526 |
5.07 |
| 2026-09-27 00:00 |
07:42:25.80 |
-18:09:50.8 |
HIP 37526 |
5.04 |
| 2026-09-27 12:00 |
07:42:26.28 |
-18:10:04.4 |
HIP 37526 |
5.02 |
| 2026-09-28 00:00 |
07:42:26.75 |
-18:10:18.1 |
HIP 37526 |
5.01 |
| 2026-09-28 12:00 |
07:42:27.21 |
-18:10:31.8 |
HIP 37526 |
5.01 |
| 2026-09-29 00:00 |
07:42:27.66 |
-18:10:45.4 |
HIP 37526 |
5.03 |
| 2026-09-29 12:00 |
07:42:28.09 |
-18:10:59.1 |
HIP 37526 |
5.05 |
| 2026-09-30 00:00 |
07:42:28.51 |
-18:11:12.9 |
HIP 37526 |
5.08 |
| 2026-09-30 12:00 |
07:42:28.92 |
-18:11:26.6 |
HIP 37526 |
5.12 |
| 2026-10-01 00:00 |
07:42:29.31 |
-18:11:40.3 |
HIP 37526 |
5.17 |
| 2026-10-01 12:00 |
07:42:29.70 |
-18:11:54.1 |
HIP 37526 |
5.22 |
| 2026-10-02 00:00 |
07:42:30.07 |
-18:12:07.9 |
HIP 37526 |
5.29 |
| 2026-10-02 12:00 |
07:42:30.43 |
-18:12:21.6 |
HIP 37526 |
5.36 |
| 2026-10-03 00:00 |
07:42:30.77 |
-18:12:35.4 |
HIP 37526 |
5.44 |
| 2026-10-03 12:00 |
07:42:31.11 |
-18:12:49.2 |
HIP 37526 |
5.53 |
| 2026-10-04 00:00 |
07:42:31.43 |
-18:13:03.0 |
HIP 37526 |
5.62 |
| 2026-10-04 12:00 |
07:42:31.74 |
-18:13:16.8 |
HIP 37526 |
5.72 |
| 2026-10-05 00:00 |
07:42:32.04 |
-18:13:30.6 |
HIP 37526 |
5.82 |
| 2026-10-05 12:00 |
07:42:32.32 |
-18:13:44.4 |
HIP 37526 |
5.93 |
| 2026-10-06 00:00 |
07:42:32.59 |
-18:13:58.3 |
HIP 37526 |
6.05 |
| 2026-10-06 12:00 |
07:42:32.85 |
-18:14:12.1 |
HIP 37526 |
6.16 |
| 2026-10-07 00:00 |
07:42:33.10 |
-18:14:25.9 |
HIP 37526 |
6.29 |
| 2026-10-07 12:00 |
07:42:33.33 |
-18:14:39.7 |
HIP 37526 |
6.41 |
| 2026-10-08 00:00 |
07:42:33.55 |
-18:14:53.5 |
HIP 37526 |
6.54 |
| 2026-10-08 12:00 |
07:42:33.76 |
-18:15:07.3 |
HIP 37526 |
6.67 |
| 2026-10-09 00:00 |
07:42:33.95 |
-18:15:21.2 |
HIP 37526 |
6.81 |
| 2026-10-09 12:00 |
07:42:34.13 |
-18:15:35.0 |
HIP 37526 |
6.94 |
| 2026-10-10 00:00 |
07:42:34.30 |
-18:15:48.8 |
HIP 37526 |
7.08 |
| 2026-10-10 12:00 |
07:42:34.45 |
-18:16:02.5 |
HIP 37526 |
7.22 |
| 2026-10-11 00:00 |
07:42:34.60 |
-18:16:16.3 |
HIP 37526 |
7.37 |