メタデータ
| 項目 |
値 |
| Designation |
C/2019 U6 (Lemmon) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2020-06-18T19:43:24.988800Z |
| Orbit solution date (soln_date, UTC) |
2022-04-16T22:12:22Z |
| Obs used |
1144 |
| NEO |
- |
| M1 |
13.200 |
| K1 |
7.750 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2019-10-31T10:24:29.952000Z |
| Discovery magnitude (MPC) |
20.50 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) |
2020-04-28.0000000 |
| e |
0.99790319 |
| q (au) |
0.914264 |
| a (au) |
436.025928 |
| i (deg) |
61.001339 |
| Ω (om, deg) |
235.705755 |
| ω (w, deg) |
329.659058 |
| M (ma, deg) |
359.994390 |
等級
散乱 + 全体線形
$$
M_a = (8.998 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
8.998 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.500 |
| k |
1.000 |
| 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 |
| 2018-11-06 |
2020-01-26 |
-9.9490 |
+4.967 |
| 2020-01-26 |
2020-04-22 |
+11.1473 |
-3.130 |
| 2020-04-22 |
2020-06-18 |
-1.0370 |
-2.413 |
| 2020-06-18 |
2020-07-26 |
+16.3476 |
-0.540 |
| 2020-07-26 |
2020-11-28 |
-5.2648 |
+1.320 |
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) |
| 2026-06-01 00:00 |
23:49:25.29 |
+49:36:10.1 |
HIP 117443 |
8.84 |
| 2026-06-01 12:00 |
23:49:28.60 |
+49:37:27.7 |
HIP 117443 |
10.16 |
| 2026-06-02 00:00 |
23:49:31.85 |
+49:38:45.3 |
HIP 117443 |
11.49 |
| 2026-06-02 12:00 |
23:49:35.03 |
+49:40:02.8 |
HIP 117443 |
12.83 |
| 2026-06-03 00:00 |
23:49:38.13 |
+49:41:20.4 |
HIP 117443 |
14.17 |
| 2026-06-03 12:00 |
23:49:41.16 |
+49:42:37.9 |
HIP 117443 |
15.51 |
| 2026-06-04 00:00 |
23:49:44.12 |
+49:43:55.3 |
HIP 117402 |
15.91 |
| 2026-06-04 12:00 |
23:49:47.01 |
+49:45:12.8 |
HIP 117402 |
15.72 |
| 2026-06-05 00:00 |
23:49:49.83 |
+49:46:30.2 |
HIP 117402 |
15.64 |
| 2026-06-05 12:00 |
23:49:52.57 |
+49:47:47.6 |
HIP 117402 |
15.67 |
| 2026-06-06 00:00 |
23:49:55.24 |
+49:49:04.9 |
HIP 117402 |
15.80 |
| 2026-06-06 12:00 |
23:49:57.83 |
+49:50:22.2 |
HIP 117402 |
16.04 |
| 2026-06-07 00:00 |
23:50:00.35 |
+49:51:39.4 |
HIP 117402 |
16.37 |
| 2026-06-07 12:00 |
23:50:02.80 |
+49:52:56.6 |
HIP 117402 |
16.79 |
| 2026-06-08 00:00 |
23:50:05.18 |
+49:54:13.7 |
HIP 117402 |
17.29 |
| 2026-06-08 12:00 |
23:50:07.48 |
+49:55:30.7 |
HIP 117402 |
17.87 |
| 2026-06-09 00:00 |
23:50:09.70 |
+49:56:47.7 |
HIP 117402 |
18.52 |
| 2026-06-09 12:00 |
23:50:11.85 |
+49:58:04.5 |
HIP 117402 |
19.22 |
| 2026-06-10 00:00 |
23:50:13.92 |
+49:59:21.3 |
HIP 117692 |
19.75 |
| 2026-06-10 12:00 |
23:50:15.92 |
+50:00:38.0 |
HIP 117692 |
18.99 |
| 2026-06-11 00:00 |
23:50:17.85 |
+50:01:54.6 |
HIP 117692 |
18.31 |
| 2026-06-11 12:00 |
23:50:19.69 |
+50:03:11.1 |
HIP 117692 |
17.71 |
| 2026-06-12 00:00 |
23:50:21.46 |
+50:04:27.5 |
HIP 117692 |
17.21 |
| 2026-06-12 12:00 |
23:50:23.16 |
+50:05:43.8 |
HIP 117692 |
16.80 |
| 2026-06-13 00:00 |
23:50:24.77 |
+50:07:00.0 |
HIP 117692 |
16.50 |
| 2026-06-13 12:00 |
23:50:26.31 |
+50:08:16.0 |
HIP 117692 |
16.31 |
| 2026-06-14 00:00 |
23:50:27.78 |
+50:09:32.0 |
HIP 117692 |
16.23 |
| 2026-06-14 12:00 |
23:50:29.16 |
+50:10:47.8 |
HIP 117692 |
16.26 |
| 2026-06-15 00:00 |
23:50:30.47 |
+50:12:03.4 |
HIP 117692 |
16.41 |
| 2026-06-15 12:00 |
23:50:31.70 |
+50:13:18.9 |
HIP 117692 |
16.66 |
| 2026-06-16 00:00 |
23:50:32.85 |
+50:14:34.3 |
HIP 117692 |
17.02 |
| 2026-06-16 12:00 |
23:50:33.92 |
+50:15:49.5 |
HIP 117692 |
17.47 |
| 2026-06-17 00:00 |
23:50:34.92 |
+50:17:04.5 |
HIP 117692 |
18.01 |
| 2026-06-17 12:00 |
23:50:35.83 |
+50:18:19.4 |
HIP 117692 |
18.63 |
| 2026-06-18 00:00 |
23:50:36.67 |
+50:19:34.1 |
HIP 117692 |
19.31 |
| 2026-06-18 12:00 |
23:50:37.43 |
+50:20:48.6 |
HIP 117692 |
20.06 |
| 2026-06-19 00:00 |
23:50:38.11 |
+50:22:02.9 |
HIP 117692 |
20.86 |
| 2026-06-19 12:00 |
23:50:38.71 |
+50:23:17.1 |
HIP 117692 |
21.71 |
| 2026-06-20 00:00 |
23:50:39.24 |
+50:24:31.0 |
HIP 117692 |
22.60 |
| 2026-06-20 12:00 |
23:50:39.68 |
+50:25:44.8 |
HIP 117692 |
23.53 |
| 2026-06-21 00:00 |
23:50:40.05 |
+50:26:58.3 |
HIP 117692 |
24.49 |
| 2026-06-21 12:00 |
23:50:40.33 |
+50:28:11.7 |
HIP 117437 |
24.95 |
| 2026-06-22 00:00 |
23:50:40.54 |
+50:29:24.8 |
HIP 117437 |
24.16 |