メタデータ
| 項目 |
値 |
| Designation |
C/2025 A1 (Lemmon) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2027-03-12T14:41:15.616320Z |
| Orbit solution date (soln_date, UTC) |
2026-05-08T13:42:12Z |
| Obs used |
454 |
| NEO |
- |
| M1 |
5.700 |
| K1 |
11.750 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2025-01-02T06:39:55.180800Z |
| Discovery magnitude (MPC) |
20.50 G |
| Discovery observatory (MPC) |
G96 · Mt. Lemmon Survey |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2025-08-01.0000000 |
| e |
1.00249964 |
| q (au) |
5.345608 |
| a (au) |
-2138.552808 |
| i (deg) |
33.424314 |
| Ω (om, deg) |
101.331000 |
| ω (w, deg) |
68.039415 |
| M (ma, deg) |
-0.005866 |
等級
散乱 + 全体線形
$$
M_a = (3.552 + 5.357\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
3.552 |
| n |
5.357 |
| gf |
0.900 |
| gb |
-0.974 |
| k |
1.000 |
| δ90 |
9.662 |
| 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) |
| 2026-05-12 00:00 |
08:37:13.92 |
+37:04:53.5 |
HIP 42364 |
13.22 |
| 2026-05-12 12:00 |
08:37:31.87 |
+37:03:54.6 |
HIP 42364 |
9.50 |
| 2026-05-13 00:00 |
08:37:49.98 |
+37:02:55.2 |
HIP 42364 |
5.76 |
| 2026-05-13 12:00 |
08:38:08.23 |
+37:01:55.4 |
HIP 42364 |
1.99 |
| 2026-05-14 00:00 |
08:38:26.64 |
+37:00:55.2 |
HIP 42364 |
1.84 |
| 2026-05-14 12:00 |
08:38:45.20 |
+36:59:54.5 |
HIP 42364 |
5.67 |
| 2026-05-15 00:00 |
08:39:03.91 |
+36:58:53.4 |
HIP 42364 |
9.54 |
| 2026-05-15 12:00 |
08:39:22.76 |
+36:57:51.9 |
HIP 42364 |
13.45 |
| 2026-05-16 00:00 |
08:39:41.77 |
+36:56:49.9 |
HIP 42364 |
17.38 |
| 2026-05-16 12:00 |
08:40:00.92 |
+36:55:47.5 |
HIP 42364 |
21.35 |
| 2026-05-17 00:00 |
08:40:20.22 |
+36:54:44.8 |
HIP 42364 |
25.34 |
| 2026-05-17 12:00 |
08:40:39.66 |
+36:53:41.6 |
HIP 42730 |
22.10 |
| 2026-05-18 00:00 |
08:40:59.24 |
+36:52:38.0 |
HIP 42730 |
18.41 |
| 2026-05-18 12:00 |
08:41:18.97 |
+36:51:34.0 |
HIP 42730 |
14.90 |
| 2026-05-19 00:00 |
08:41:38.84 |
+36:50:29.6 |
HIP 42730 |
11.73 |
| 2026-05-19 12:00 |
08:41:58.85 |
+36:49:24.8 |
HIP 42730 |
9.33 |
| 2026-05-20 00:00 |
08:42:19.01 |
+36:48:19.6 |
HIP 42730 |
8.41 |
| 2026-05-20 12:00 |
08:42:39.30 |
+36:47:14.0 |
HIP 42730 |
9.45 |
| 2026-05-21 00:00 |
08:42:59.72 |
+36:46:08.1 |
HIP 42824 |
7.57 |
| 2026-05-21 12:00 |
08:43:20.29 |
+36:45:01.7 |
HIP 42824 |
3.46 |
| 2026-05-22 00:00 |
08:43:40.99 |
+36:43:55.0 |
HIP 42824 |
1.75 |
| 2026-05-22 12:00 |
08:44:01.82 |
+36:42:47.9 |
HIP 42824 |
5.60 |
| 2026-05-23 00:00 |
08:44:22.79 |
+36:41:40.5 |
HIP 42824 |
9.88 |
| 2026-05-23 12:00 |
08:44:43.89 |
+36:40:32.7 |
HIP 42824 |
14.23 |
| 2026-05-24 00:00 |
08:45:05.13 |
+36:39:24.5 |
HIP 42824 |
18.62 |
| 2026-05-24 12:00 |
08:45:26.49 |
+36:38:16.0 |
HIP 42871 |
22.75 |
| 2026-05-25 00:00 |
08:45:47.98 |
+36:37:07.1 |
HIP 43155 |
21.52 |
| 2026-05-25 12:00 |
08:46:09.60 |
+36:35:57.8 |
HIP 43155 |
17.15 |
| 2026-05-26 00:00 |
08:46:31.35 |
+36:34:48.2 |
HIP 43155 |
12.85 |
| 2026-05-26 12:00 |
08:46:53.23 |
+36:33:38.3 |
HIP 43155 |
8.73 |
| 2026-05-27 00:00 |
08:47:15.23 |
+36:32:28.0 |
HIP 43155 |
5.35 |
| 2026-05-27 12:00 |
08:47:37.36 |
+36:31:17.4 |
HIP 43155 |
4.79 |
| 2026-05-28 00:00 |
08:47:59.61 |
+36:30:06.4 |
HIP 43155 |
7.74 |
| 2026-05-28 12:00 |
08:48:21.98 |
+36:28:55.1 |
HIP 43296 |
10.36 |
| 2026-05-29 00:00 |
08:48:44.47 |
+36:27:43.5 |
HIP 43296 |
6.69 |
| 2026-05-29 12:00 |
08:49:07.09 |
+36:26:31.5 |
HIP 43296 |
5.10 |
| 2026-05-30 00:00 |
08:49:29.83 |
+36:25:19.2 |
HIP 43296 |
7.19 |
| 2026-05-30 12:00 |
08:49:52.68 |
+36:24:06.5 |
HIP 43296 |
11.07 |
| 2026-05-31 00:00 |
08:50:15.66 |
+36:22:53.6 |
HIP 43296 |
15.47 |
| 2026-05-31 12:00 |
08:50:38.75 |
+36:21:40.3 |
HIP 43296 |
20.07 |
| 2026-06-01 00:00 |
08:51:01.96 |
+36:20:26.7 |
HIP 43296 |
24.77 |
| 2026-06-01 12:00 |
08:51:25.29 |
+36:19:12.8 |
HIP 43296 |
29.53 |
| 2026-06-02 00:00 |
08:51:48.73 |
+36:17:58.5 |
HIP 43296 |
34.35 |