メタデータ
| 項目 |
値 |
| Designation |
C/2021 T1 (Lemmon) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2021-10-14T01:40:49.874880Z |
| Orbit solution date (soln_date, UTC) |
2022-07-31T01:43:17Z |
| Obs used |
114 |
| NEO |
- |
| M1 |
11.500 |
| K1 |
13.250 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2021-10-02T04:59:50.640000Z |
| Discovery magnitude (MPC) |
20.04 G |
| Discovery observatory (MPC) |
G96 · University of Arizona Mt. Lemmon Survey |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2021-12-07.0000000 |
| e |
0.99796291 |
| q (au) |
3.058012 |
| a (au) |
1501.163873 |
| i (deg) |
140.350038 |
| Ω (om, deg) |
56.816270 |
| ω (w, deg) |
51.501528 |
| M (ma, deg) |
0.000914 |
等級
散乱 + 全体線形
$$
M_a = (10.107 + 5.998\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
10.107 |
| n |
5.998 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.999 |
| 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) |
| 2026-09-20 00:00 |
15:39:52.22 |
-16:45:47.3 |
HIP 76787 |
11.57 |
| 2026-09-20 12:00 |
15:39:55.28 |
-16:46:17.1 |
HIP 76787 |
10.87 |
| 2026-09-21 00:00 |
15:39:58.39 |
-16:46:47.1 |
HIP 76787 |
10.18 |
| 2026-09-21 12:00 |
15:40:01.57 |
-16:47:17.1 |
HIP 76787 |
9.52 |
| 2026-09-22 00:00 |
15:40:04.80 |
-16:47:47.4 |
HIP 76787 |
8.89 |
| 2026-09-22 12:00 |
15:40:08.08 |
-16:48:17.7 |
HIP 76787 |
8.30 |
| 2026-09-23 00:00 |
15:40:11.42 |
-16:48:48.2 |
HIP 76787 |
7.78 |
| 2026-09-23 12:00 |
15:40:14.82 |
-16:49:18.9 |
HIP 76787 |
7.32 |
| 2026-09-24 00:00 |
15:40:18.27 |
-16:49:49.6 |
HIP 76787 |
6.96 |
| 2026-09-24 12:00 |
15:40:21.78 |
-16:50:20.5 |
HIP 76787 |
6.72 |
| 2026-09-25 00:00 |
15:40:25.34 |
-16:50:51.5 |
HIP 76787 |
6.61 |
| 2026-09-25 12:00 |
15:40:28.96 |
-16:51:22.6 |
HIP 76787 |
6.64 |
| 2026-09-26 00:00 |
15:40:32.63 |
-16:51:53.8 |
HIP 76787 |
6.82 |
| 2026-09-26 12:00 |
15:40:36.35 |
-16:52:25.2 |
HIP 76787 |
7.15 |
| 2026-09-27 00:00 |
15:40:40.13 |
-16:52:56.7 |
HIP 76787 |
7.61 |
| 2026-09-27 12:00 |
15:40:43.95 |
-16:53:28.2 |
HIP 76787 |
8.17 |
| 2026-09-28 00:00 |
15:40:47.83 |
-16:54:00.0 |
HIP 76787 |
8.84 |
| 2026-09-28 12:00 |
15:40:51.76 |
-16:54:31.8 |
HIP 76787 |
9.58 |
| 2026-09-29 00:00 |
15:40:55.75 |
-16:55:03.7 |
HIP 76787 |
10.39 |
| 2026-09-29 12:00 |
15:40:59.78 |
-16:55:35.7 |
HIP 76787 |
11.25 |
| 2026-09-30 00:00 |
15:41:03.86 |
-16:56:07.9 |
HIP 76787 |
12.16 |
| 2026-09-30 12:00 |
15:41:08.00 |
-16:56:40.1 |
HIP 76879 |
11.76 |
| 2026-10-01 00:00 |
15:41:12.18 |
-16:57:12.5 |
HIP 76879 |
10.87 |
| 2026-10-01 12:00 |
15:41:16.42 |
-16:57:45.0 |
HIP 76879 |
10.03 |
| 2026-10-02 00:00 |
15:41:20.70 |
-16:58:17.5 |
HIP 76879 |
9.24 |
| 2026-10-02 12:00 |
15:41:25.03 |
-16:58:50.2 |
HIP 76879 |
8.52 |
| 2026-10-03 00:00 |
15:41:29.41 |
-16:59:23.0 |
HIP 76879 |
7.90 |
| 2026-10-03 12:00 |
15:41:33.84 |
-16:59:55.8 |
HIP 76879 |
7.42 |
| 2026-10-04 00:00 |
15:41:38.31 |
-17:00:28.8 |
HIP 76879 |
7.10 |
| 2026-10-04 12:00 |
15:41:42.84 |
-17:01:01.8 |
HIP 76879 |
6.97 |
| 2026-10-05 00:00 |
15:41:47.41 |
-17:01:35.0 |
HIP 76879 |
7.05 |
| 2026-10-05 12:00 |
15:41:52.02 |
-17:02:08.2 |
HIP 76879 |
7.34 |
| 2026-10-06 00:00 |
15:41:56.68 |
-17:02:41.6 |
HIP 76879 |
7.81 |
| 2026-10-06 12:00 |
15:42:01.39 |
-17:03:15.0 |
HIP 76879 |
8.44 |
| 2026-10-07 00:00 |
15:42:06.14 |
-17:03:48.5 |
HIP 76879 |
9.21 |
| 2026-10-07 12:00 |
15:42:10.94 |
-17:04:22.1 |
HIP 76879 |
10.09 |
| 2026-10-08 00:00 |
15:42:15.78 |
-17:04:55.7 |
HIP 76879 |
11.04 |
| 2026-10-08 12:00 |
15:42:20.67 |
-17:05:29.5 |
HIP 76879 |
12.07 |
| 2026-10-09 00:00 |
15:42:25.59 |
-17:06:03.3 |
HIP 76879 |
13.15 |
| 2026-10-09 12:00 |
15:42:30.57 |
-17:06:37.2 |
HIP 76879 |
14.27 |
| 2026-10-10 00:00 |
15:42:35.58 |
-17:07:11.2 |
HIP 76879 |
15.44 |
| 2026-10-10 12:00 |
15:42:40.64 |
-17:07:45.3 |
HIP 76879 |
16.63 |
| 2026-10-11 00:00 |
15:42:45.73 |
-17:08:19.4 |
HIP 76879 |
17.85 |