メタデータ
| 項目 |
値 |
| Designation |
C/2015 XY1 (Lemmon) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2018-04-29T23:09:25.130880Z |
| Orbit solution date (soln_date, UTC) |
2022-07-31T01:42:27Z |
| Obs used |
741 |
| NEO |
- |
| M1 |
6.400 |
| K1 |
8.250 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2018-03-20.0000000 |
| e |
1.00401907 |
| q (au) |
7.927954 |
| a (au) |
-1972.582314 |
| i (deg) |
148.846771 |
| Ω (om, deg) |
281.616004 |
| ω (w, deg) |
196.354336 |
| M (ma, deg) |
-0.000461 |
等級
散乱 + 全体線形
$$
M_a = (-0.855 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
-0.855 |
| n |
6.000 |
| gf |
0.882 |
| gb |
-0.939 |
| k |
1.000 |
| δ90 |
3.868 |
| 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) |
| 2026-06-01 00:00 |
00:07:30.47 |
-30:12:32.5 |
HIP 653 |
12.62 |
| 2026-06-01 12:00 |
00:07:31.35 |
-30:13:12.4 |
HIP 653 |
13.09 |
| 2026-06-02 00:00 |
00:07:32.17 |
-30:13:52.8 |
HIP 653 |
13.59 |
| 2026-06-02 12:00 |
00:07:32.94 |
-30:14:33.6 |
HIP 653 |
14.12 |
| 2026-06-03 00:00 |
00:07:33.66 |
-30:15:14.9 |
HIP 653 |
14.68 |
| 2026-06-03 12:00 |
00:07:34.32 |
-30:15:56.5 |
HIP 653 |
15.25 |
| 2026-06-04 00:00 |
00:07:34.93 |
-30:16:38.6 |
HIP 653 |
15.85 |
| 2026-06-04 12:00 |
00:07:35.49 |
-30:17:21.2 |
HIP 653 |
16.47 |
| 2026-06-05 00:00 |
00:07:35.99 |
-30:18:04.1 |
HIP 585 |
16.77 |
| 2026-06-05 12:00 |
00:07:36.43 |
-30:18:47.5 |
HIP 585 |
16.13 |
| 2026-06-06 00:00 |
00:07:36.83 |
-30:19:31.3 |
HIP 585 |
15.49 |
| 2026-06-06 12:00 |
00:07:37.16 |
-30:20:15.5 |
HIP 585 |
14.85 |
| 2026-06-07 00:00 |
00:07:37.45 |
-30:21:00.1 |
HIP 585 |
14.21 |
| 2026-06-07 12:00 |
00:07:37.67 |
-30:21:45.2 |
HIP 585 |
13.57 |
| 2026-06-08 00:00 |
00:07:37.84 |
-30:22:30.6 |
HIP 585 |
12.92 |
| 2026-06-08 12:00 |
00:07:37.96 |
-30:23:16.5 |
HIP 585 |
12.28 |
| 2026-06-09 00:00 |
00:07:38.02 |
-30:24:02.7 |
HIP 585 |
11.64 |
| 2026-06-09 12:00 |
00:07:38.02 |
-30:24:49.4 |
HIP 585 |
11.00 |
| 2026-06-10 00:00 |
00:07:37.97 |
-30:25:36.5 |
HIP 585 |
10.37 |
| 2026-06-10 12:00 |
00:07:37.86 |
-30:26:23.9 |
HIP 585 |
9.75 |
| 2026-06-11 00:00 |
00:07:37.69 |
-30:27:11.8 |
HIP 585 |
9.15 |
| 2026-06-11 12:00 |
00:07:37.46 |
-30:28:00.1 |
HIP 585 |
8.56 |
| 2026-06-12 00:00 |
00:07:37.18 |
-30:28:48.7 |
HIP 585 |
7.99 |
| 2026-06-12 12:00 |
00:07:36.84 |
-30:29:37.8 |
HIP 585 |
7.46 |
| 2026-06-13 00:00 |
00:07:36.44 |
-30:30:27.2 |
HIP 585 |
6.97 |
| 2026-06-13 12:00 |
00:07:35.99 |
-30:31:17.0 |
HIP 585 |
6.53 |
| 2026-06-14 00:00 |
00:07:35.48 |
-30:32:07.3 |
HIP 585 |
6.16 |
| 2026-06-14 12:00 |
00:07:34.90 |
-30:32:57.8 |
HIP 585 |
5.88 |
| 2026-06-15 00:00 |
00:07:34.27 |
-30:33:48.8 |
HIP 585 |
5.70 |
| 2026-06-15 12:00 |
00:07:33.59 |
-30:34:40.1 |
HIP 585 |
5.64 |
| 2026-06-16 00:00 |
00:07:32.84 |
-30:35:31.8 |
HIP 585 |
5.69 |
| 2026-06-16 12:00 |
00:07:32.03 |
-30:36:23.9 |
HIP 585 |
5.88 |
| 2026-06-17 00:00 |
00:07:31.17 |
-30:37:16.3 |
HIP 585 |
6.17 |
| 2026-06-17 12:00 |
00:07:30.24 |
-30:38:09.1 |
HIP 585 |
6.57 |
| 2026-06-18 00:00 |
00:07:29.26 |
-30:39:02.2 |
HIP 585 |
7.06 |
| 2026-06-18 12:00 |
00:07:28.21 |
-30:39:55.7 |
HIP 585 |
7.63 |
| 2026-06-19 00:00 |
00:07:27.11 |
-30:40:49.5 |
HIP 570 |
8.07 |
| 2026-06-19 12:00 |
00:07:25.95 |
-30:41:43.7 |
HIP 570 |
8.39 |
| 2026-06-20 00:00 |
00:07:24.72 |
-30:42:38.2 |
HIP 570 |
8.79 |
| 2026-06-20 12:00 |
00:07:23.44 |
-30:43:33.1 |
HIP 570 |
9.27 |
| 2026-06-21 00:00 |
00:07:22.10 |
-30:44:28.3 |
HIP 570 |
9.82 |
| 2026-06-21 12:00 |
00:07:20.70 |
-30:45:23.8 |
HIP 570 |
10.42 |
| 2026-06-22 00:00 |
00:07:19.24 |
-30:46:19.6 |
HIP 570 |
11.08 |