メタデータ
| 項目 |
値 |
| Designation |
C/1968 Y1 (Thomas) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1969-01-12T06:16:18.609600Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:19Z |
| Obs used |
43 |
| NEO |
- |
| M1 |
5.800 |
| K1 |
10.500 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
1969-02-14.0000000 |
| e |
0.99530224 |
| q (au) |
3.316098 |
| a (au) |
705.888695 |
| i (deg) |
45.229346 |
| Ω (om, deg) |
16.110035 |
| ω (w, deg) |
82.582846 |
| M (ma, deg) |
0.001721 |
等級
散乱 + 全体線形
$$
M_a = (6.454 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
6.454 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.800 |
| 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
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
15:36:44.26 |
-58:39:29.1 |
HIP 76394 |
9.80 |
| 2026-03-26 12:00 |
15:36:42.60 |
-58:39:38.3 |
HIP 76394 |
9.56 |
| 2026-03-27 00:00 |
15:36:40.92 |
-58:39:47.5 |
HIP 76394 |
9.33 |
| 2026-03-27 12:00 |
15:36:39.22 |
-58:39:56.6 |
HIP 76394 |
9.10 |
| 2026-03-28 00:00 |
15:36:37.50 |
-58:40:05.5 |
HIP 76394 |
8.88 |
| 2026-03-28 12:00 |
15:36:35.76 |
-58:40:14.4 |
HIP 76394 |
8.66 |
| 2026-03-29 00:00 |
15:36:34.00 |
-58:40:23.1 |
HIP 76394 |
8.44 |
| 2026-03-29 12:00 |
15:36:32.23 |
-58:40:31.8 |
HIP 76394 |
8.22 |
| 2026-03-30 00:00 |
15:36:30.43 |
-58:40:40.3 |
HIP 76394 |
8.01 |
| 2026-03-30 12:00 |
15:36:28.62 |
-58:40:48.7 |
HIP 76394 |
7.80 |
| 2026-03-31 00:00 |
15:36:26.79 |
-58:40:57.0 |
HIP 76394 |
7.60 |
| 2026-03-31 12:00 |
15:36:24.94 |
-58:41:05.2 |
HIP 76394 |
7.41 |
| 2026-04-01 00:00 |
15:36:23.08 |
-58:41:13.3 |
HIP 76394 |
7.22 |
| 2026-04-01 12:00 |
15:36:21.20 |
-58:41:21.2 |
HIP 76394 |
7.04 |
| 2026-04-02 00:00 |
15:36:19.30 |
-58:41:29.1 |
HIP 76394 |
6.87 |
| 2026-04-02 12:00 |
15:36:17.38 |
-58:41:36.9 |
HIP 76394 |
6.70 |
| 2026-04-03 00:00 |
15:36:15.44 |
-58:41:44.5 |
HIP 76394 |
6.55 |
| 2026-04-03 12:00 |
15:36:13.49 |
-58:41:52.0 |
HIP 76394 |
6.40 |
| 2026-04-04 00:00 |
15:36:11.52 |
-58:41:59.4 |
HIP 76394 |
6.27 |
| 2026-04-04 12:00 |
15:36:09.54 |
-58:42:06.7 |
HIP 76394 |
6.15 |
| 2026-04-05 00:00 |
15:36:07.54 |
-58:42:13.9 |
HIP 76394 |
6.04 |
| 2026-04-05 12:00 |
15:36:05.52 |
-58:42:20.9 |
HIP 76394 |
5.95 |
| 2026-04-06 00:00 |
15:36:03.48 |
-58:42:27.9 |
HIP 76394 |
5.87 |
| 2026-04-06 12:00 |
15:36:01.43 |
-58:42:34.7 |
HIP 76394 |
5.80 |
| 2026-04-07 00:00 |
15:35:59.36 |
-58:42:41.4 |
HIP 76394 |
5.76 |
| 2026-04-07 12:00 |
15:35:57.28 |
-58:42:48.0 |
HIP 76394 |
5.73 |
| 2026-04-08 00:00 |
15:35:55.18 |
-58:42:54.5 |
HIP 76394 |
5.71 |
| 2026-04-08 12:00 |
15:35:53.07 |
-58:43:00.8 |
HIP 76394 |
5.72 |
| 2026-04-09 00:00 |
15:35:50.94 |
-58:43:07.1 |
HIP 76394 |
5.74 |
| 2026-04-09 12:00 |
15:35:48.80 |
-58:43:13.2 |
HIP 76394 |
5.78 |
| 2026-04-10 00:00 |
15:35:46.64 |
-58:43:19.2 |
HIP 76394 |
5.84 |
| 2026-04-10 12:00 |
15:35:44.46 |
-58:43:25.1 |
HIP 76394 |
5.91 |
| 2026-04-11 00:00 |
15:35:42.27 |
-58:43:30.8 |
HIP 76394 |
6.00 |
| 2026-04-11 12:00 |
15:35:40.07 |
-58:43:36.4 |
HIP 76394 |
6.11 |
| 2026-04-12 00:00 |
15:35:37.85 |
-58:43:41.9 |
HIP 76394 |
6.23 |
| 2026-04-12 12:00 |
15:35:35.62 |
-58:43:47.3 |
HIP 76394 |
6.37 |
| 2026-04-13 00:00 |
15:35:33.37 |
-58:43:52.6 |
HIP 76394 |
6.52 |
| 2026-04-13 12:00 |
15:35:31.11 |
-58:43:57.7 |
HIP 76394 |
6.69 |
| 2026-04-14 00:00 |
15:35:28.84 |
-58:44:02.7 |
HIP 76394 |
6.86 |
| 2026-04-14 12:00 |
15:35:26.55 |
-58:44:07.6 |
HIP 76394 |
7.05 |
| 2026-04-15 00:00 |
15:35:24.25 |
-58:44:12.4 |
HIP 76394 |
7.25 |
| 2026-04-15 12:00 |
15:35:21.94 |
-58:44:17.0 |
HIP 76394 |
7.46 |
| 2026-04-16 00:00 |
15:35:19.61 |
-58:44:21.5 |
HIP 76394 |
7.68 |