C/2017 S7 (Lemmon)
メタデータ
| 項目 |
値 |
| Designation |
C/2017 S7 (Lemmon) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2017-05-27T21:16:49.696320Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:36Z |
| Obs used |
157 |
| NEO |
- |
| M1 |
6.700 |
| K1 |
10.000 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2017-11-16.0000000 |
| e |
1.00249982 |
| q (au) |
7.614408 |
| a (au) |
-3045.987574 |
| i (deg) |
124.224743 |
| Ω (om, deg) |
262.788416 |
| ω (w, deg) |
187.747383 |
| M (ma, deg) |
0.001009 |
等級
散乱 + 全体線形
$$
M_a = (1.282 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
1.282 |
| n |
6.000 |
| gf |
0.998 |
| gb |
-0.721 |
| 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
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-02-03 00:00 |
23:23:17.48 |
-59:16:24.1 |
HIP 115517 |
15.94 |
| 2026-02-03 12:00 |
23:23:24.01 |
-59:15:27.0 |
HIP 115517 |
16.58 |
| 2026-02-04 00:00 |
23:23:30.59 |
-59:14:30.4 |
HIP 115517 |
17.29 |
| 2026-02-04 12:00 |
23:23:37.22 |
-59:13:34.2 |
HIP 115517 |
18.04 |
| 2026-02-05 00:00 |
23:23:43.90 |
-59:12:38.4 |
HIP 115380 |
18.68 |
| 2026-02-05 12:00 |
23:23:50.62 |
-59:11:43.0 |
HIP 115380 |
18.43 |
| 2026-02-06 00:00 |
23:23:57.39 |
-59:10:48.1 |
HIP 115380 |
18.28 |
| 2026-02-06 12:00 |
23:24:04.21 |
-59:09:53.6 |
HIP 115380 |
18.22 |
| 2026-02-07 00:00 |
23:24:11.06 |
-59:08:59.6 |
HIP 115380 |
18.25 |
| 2026-02-07 12:00 |
23:24:17.96 |
-59:08:06.0 |
HIP 115380 |
18.39 |
| 2026-02-08 00:00 |
23:24:24.91 |
-59:07:12.8 |
HIP 115380 |
18.61 |
| 2026-02-08 12:00 |
23:24:31.89 |
-59:06:20.1 |
HIP 115380 |
18.93 |
| 2026-02-09 00:00 |
23:24:38.92 |
-59:05:27.9 |
HIP 115380 |
19.33 |
| 2026-02-09 12:00 |
23:24:45.99 |
-59:04:36.1 |
HIP 115380 |
19.82 |
| 2026-02-10 00:00 |
23:24:53.10 |
-59:03:44.8 |
HIP 115380 |
20.37 |
| 2026-02-10 12:00 |
23:25:00.24 |
-59:02:53.9 |
HIP 115380 |
21.00 |
| 2026-02-11 00:00 |
23:25:07.43 |
-59:02:03.5 |
HIP 115380 |
21.68 |
| 2026-02-11 12:00 |
23:25:14.66 |
-59:01:13.6 |
HIP 115380 |
22.42 |
| 2026-02-12 00:00 |
23:25:21.92 |
-59:00:24.1 |
HIP 115380 |
23.22 |
| 2026-02-12 12:00 |
23:25:29.22 |
-58:59:35.2 |
HIP 115380 |
24.05 |
| 2026-02-13 00:00 |
23:25:36.56 |
-58:58:46.7 |
HIP 115380 |
24.93 |
| 2026-02-13 12:00 |
23:25:43.93 |
-58:57:58.7 |
HIP 115380 |
25.84 |
| 2026-02-14 00:00 |
23:25:51.34 |
-58:57:11.2 |
HIP 115380 |
26.79 |
| 2026-02-14 12:00 |
23:25:58.78 |
-58:56:24.2 |
HIP 115380 |
27.76 |
| 2026-02-15 00:00 |
23:26:06.25 |
-58:55:37.7 |
HIP 115769 |
28.48 |
| 2026-02-15 12:00 |
23:26:13.76 |
-58:54:51.7 |
HIP 115769 |
27.46 |
| 2026-02-16 00:00 |
23:26:21.30 |
-58:54:06.2 |
HIP 115769 |
26.46 |
| 2026-02-16 12:00 |
23:26:28.88 |
-58:53:21.1 |
HIP 115769 |
25.49 |
| 2026-02-17 00:00 |
23:26:36.48 |
-58:52:36.6 |
HIP 115769 |
24.55 |
| 2026-02-17 12:00 |
23:26:44.11 |
-58:51:52.7 |
HIP 115769 |
23.64 |
| 2026-02-18 00:00 |
23:26:51.78 |
-58:51:09.2 |
HIP 115769 |
22.78 |
| 2026-02-18 12:00 |
23:26:59.47 |
-58:50:26.2 |
HIP 115769 |
21.95 |
| 2026-02-19 00:00 |
23:27:07.19 |
-58:49:43.8 |
HIP 115769 |
21.18 |
| 2026-02-19 12:00 |
23:27:14.94 |
-58:49:01.9 |
HIP 115769 |
20.45 |
| 2026-02-20 00:00 |
23:27:22.71 |
-58:48:20.5 |
HIP 115769 |
19.79 |
| 2026-02-20 12:00 |
23:27:30.51 |
-58:47:39.7 |
HIP 115769 |
19.19 |
| 2026-02-21 00:00 |
23:27:38.34 |
-58:46:59.3 |
HIP 115769 |
18.66 |
| 2026-02-21 12:00 |
23:27:46.19 |
-58:46:19.5 |
HIP 115769 |
18.21 |
| 2026-02-22 00:00 |
23:27:54.06 |
-58:45:40.3 |
HIP 115769 |
17.84 |
| 2026-02-22 12:00 |
23:28:01.96 |
-58:45:01.6 |
HIP 115769 |
17.55 |
| 2026-02-23 00:00 |
23:28:09.88 |
-58:44:23.4 |
HIP 115769 |
17.36 |
| 2026-02-23 12:00 |
23:28:17.82 |
-58:43:45.8 |
HIP 115769 |
17.25 |
| 2026-02-24 00:00 |
23:28:25.78 |
-58:43:08.7 |
HIP 115769 |
17.25 |