メタデータ
| 項目 |
値 |
| Designation |
C/2021 C6 (Lemmon) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2021-11-13T08:19:46.225920Z |
| Orbit solution date (soln_date, UTC) |
2022-12-28T10:16:54Z |
| Obs used |
199 |
| NEO |
- |
| M1 |
15.600 |
| K1 |
4.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2021-02-07T10:22:20.006400Z |
| Discovery magnitude (MPC) |
20.86 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) |
2021-09-15.0000000 |
| e |
1.00185407 |
| q (au) |
3.271189 |
| a (au) |
-1764.328257 |
| i (deg) |
164.625857 |
| Ω (om, deg) |
332.155949 |
| ω (w, deg) |
203.567737 |
| M (ma, deg) |
-0.000789 |
等級
散乱 + 全体線形
$$
M_a = (15.001 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
15.001 |
| n |
2.000 |
| gf |
0.929 |
| gb |
-0.889 |
| k |
1.000 |
| δ90 |
1.000 |
| 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 |
| 2021-01-23 |
2021-11-09 |
-4.1916 |
+2.446 |
| 2021-11-28 |
2022-12-15 |
+13.4351 |
-7.126 |
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 |
00:57:05.18 |
-03:24:19.3 |
HIP 4374 |
25.41 |
| 2026-06-01 12:00 |
00:57:07.97 |
-03:24:14.4 |
HIP 4374 |
25.91 |
| 2026-06-02 00:00 |
00:57:10.70 |
-03:24:09.9 |
HIP 4374 |
26.40 |
| 2026-06-02 12:00 |
00:57:13.37 |
-03:24:05.9 |
HIP 4374 |
26.89 |
| 2026-06-03 00:00 |
00:57:15.99 |
-03:24:02.4 |
HIP 4374 |
27.37 |
| 2026-06-03 12:00 |
00:57:18.56 |
-03:23:59.2 |
HIP 4374 |
27.84 |
| 2026-06-04 00:00 |
00:57:21.07 |
-03:23:56.6 |
HIP 4374 |
28.31 |
| 2026-06-04 12:00 |
00:57:23.52 |
-03:23:54.3 |
HIP 4374 |
28.76 |
| 2026-06-05 00:00 |
00:57:25.92 |
-03:23:52.5 |
HIP 4374 |
29.21 |
| 2026-06-05 12:00 |
00:57:28.26 |
-03:23:51.2 |
HIP 4374 |
29.65 |
| 2026-06-06 00:00 |
00:57:30.55 |
-03:23:50.3 |
HIP 4374 |
30.07 |
| 2026-06-06 12:00 |
00:57:32.78 |
-03:23:49.9 |
HIP 4374 |
30.49 |
| 2026-06-07 00:00 |
00:57:34.95 |
-03:23:49.9 |
HIP 4374 |
30.89 |
| 2026-06-07 12:00 |
00:57:37.07 |
-03:23:50.4 |
HIP 4374 |
31.28 |
| 2026-06-08 00:00 |
00:57:39.12 |
-03:23:51.4 |
HIP 4374 |
31.66 |
| 2026-06-08 12:00 |
00:57:41.12 |
-03:23:52.8 |
HIP 4374 |
32.03 |
| 2026-06-09 00:00 |
00:57:43.06 |
-03:23:54.6 |
HIP 4374 |
32.39 |
| 2026-06-09 12:00 |
00:57:44.94 |
-03:23:57.0 |
HIP 4374 |
32.73 |
| 2026-06-10 00:00 |
00:57:46.77 |
-03:23:59.7 |
HIP 4374 |
33.06 |
| 2026-06-10 12:00 |
00:57:48.53 |
-03:24:03.0 |
HIP 4374 |
33.37 |
| 2026-06-11 00:00 |
00:57:50.23 |
-03:24:06.7 |
HIP 4374 |
33.67 |
| 2026-06-11 12:00 |
00:57:51.87 |
-03:24:10.8 |
HIP 4374 |
33.96 |
| 2026-06-12 00:00 |
00:57:53.45 |
-03:24:15.5 |
HIP 4374 |
34.24 |
| 2026-06-12 12:00 |
00:57:54.98 |
-03:24:20.6 |
HIP 4374 |
34.50 |
| 2026-06-13 00:00 |
00:57:56.44 |
-03:24:26.1 |
HIP 4374 |
34.74 |
| 2026-06-13 12:00 |
00:57:57.83 |
-03:24:32.2 |
HIP 4374 |
34.97 |
| 2026-06-14 00:00 |
00:57:59.17 |
-03:24:38.7 |
HIP 4374 |
35.19 |
| 2026-06-14 12:00 |
00:58:00.44 |
-03:24:45.7 |
HIP 4374 |
35.39 |
| 2026-06-15 00:00 |
00:58:01.65 |
-03:24:53.1 |
HIP 4374 |
35.57 |
| 2026-06-15 12:00 |
00:58:02.80 |
-03:25:01.0 |
HIP 4374 |
35.74 |
| 2026-06-16 00:00 |
00:58:03.89 |
-03:25:09.4 |
HIP 4374 |
35.89 |
| 2026-06-16 12:00 |
00:58:04.91 |
-03:25:18.3 |
HIP 4374 |
36.03 |
| 2026-06-17 00:00 |
00:58:05.87 |
-03:25:27.6 |
HIP 4374 |
36.15 |
| 2026-06-17 12:00 |
00:58:06.76 |
-03:25:37.4 |
HIP 4374 |
36.26 |
| 2026-06-18 00:00 |
00:58:07.59 |
-03:25:47.6 |
HIP 4374 |
36.35 |
| 2026-06-18 12:00 |
00:58:08.35 |
-03:25:58.4 |
HIP 4374 |
36.42 |
| 2026-06-19 00:00 |
00:58:09.05 |
-03:26:09.6 |
HIP 4374 |
36.48 |
| 2026-06-19 12:00 |
00:58:09.69 |
-03:26:21.3 |
HIP 4374 |
36.52 |
| 2026-06-20 00:00 |
00:58:10.26 |
-03:26:33.4 |
HIP 4374 |
36.55 |
| 2026-06-20 12:00 |
00:58:10.76 |
-03:26:46.1 |
HIP 4374 |
36.56 |
| 2026-06-21 00:00 |
00:58:11.20 |
-03:26:59.2 |
HIP 4374 |
36.55 |
| 2026-06-21 12:00 |
00:58:11.57 |
-03:27:12.7 |
HIP 4374 |
36.52 |
| 2026-06-22 00:00 |
00:58:11.88 |
-03:27:26.8 |
HIP 4374 |
36.48 |