メタデータ
| 項目 |
値 |
| Designation |
C/2021 F1 (Lemmon-PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2022-04-06T21:01:27.013440Z |
| Orbit solution date (soln_date, UTC) |
2023-04-24T19:06:41Z |
| Obs used |
403 |
| NEO |
- |
| M1 |
12.900 |
| K1 |
10.500 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2022-03-03.0000000 |
| e |
0.99570134 |
| q (au) |
0.995447 |
| a (au) |
231.571420 |
| i (deg) |
107.324992 |
| Ω (om, deg) |
203.451604 |
| ω (w, deg) |
146.826095 |
| M (ma, deg) |
359.990246 |
等級
散乱 + 全体線形
$$
M_a = (13.444 + 4.948\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
13.444 |
| n |
4.948 |
| gf |
0.997 |
| gb |
-1.000 |
| k |
0.800 |
| 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 |
| 2022-01-07 |
2022-03-31 |
+7.4996 |
-2.051 |
| 2022-05-30 |
2022-09-02 |
+5.5948 |
-3.888 |
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) |
| 2026-07-29 00:00 |
11:53:55.83 |
-69:50:26.5 |
HIP 57928 |
6.05 |
| 2026-07-29 12:00 |
11:54:11.17 |
-69:48:52.5 |
HIP 57928 |
7.97 |
| 2026-07-30 00:00 |
11:54:26.61 |
-69:47:19.2 |
HIP 57956 |
9.85 |
| 2026-07-30 12:00 |
11:54:42.14 |
-69:45:46.6 |
HIP 57956 |
9.76 |
| 2026-07-31 00:00 |
11:54:57.77 |
-69:44:14.9 |
HIP 57956 |
10.11 |
| 2026-07-31 12:00 |
11:55:13.50 |
-69:42:43.8 |
HIP 57956 |
10.86 |
| 2026-08-01 00:00 |
11:55:29.31 |
-69:41:13.5 |
HIP 57956 |
11.92 |
| 2026-08-01 12:00 |
11:55:45.22 |
-69:39:44.0 |
HIP 57956 |
13.22 |
| 2026-08-02 00:00 |
11:56:01.21 |
-69:38:15.2 |
HIP 57956 |
14.70 |
| 2026-08-02 12:00 |
11:56:17.30 |
-69:36:47.2 |
HIP 57956 |
16.31 |
| 2026-08-03 00:00 |
11:56:33.47 |
-69:35:20.0 |
HIP 57956 |
18.01 |
| 2026-08-03 12:00 |
11:56:49.73 |
-69:33:53.5 |
HIP 57956 |
19.77 |
| 2026-08-04 00:00 |
11:57:06.08 |
-69:32:27.8 |
HIP 57956 |
21.59 |
| 2026-08-04 12:00 |
11:57:22.51 |
-69:31:02.9 |
HIP 57956 |
23.44 |
| 2026-08-05 00:00 |
11:57:39.03 |
-69:29:38.7 |
HIP 57956 |
25.33 |
| 2026-08-05 12:00 |
11:57:55.63 |
-69:28:15.4 |
HIP 58709 |
24.49 |
| 2026-08-06 00:00 |
11:58:12.31 |
-69:26:52.8 |
HIP 58709 |
22.82 |
| 2026-08-06 12:00 |
11:58:29.08 |
-69:25:31.0 |
HIP 58709 |
21.22 |
| 2026-08-07 00:00 |
11:58:45.93 |
-69:24:10.0 |
HIP 58709 |
19.67 |
| 2026-08-07 12:00 |
11:59:02.86 |
-69:22:49.7 |
HIP 58662 |
18.01 |
| 2026-08-08 00:00 |
11:59:19.86 |
-69:21:30.3 |
HIP 58662 |
16.02 |
| 2026-08-08 12:00 |
11:59:36.95 |
-69:20:11.7 |
HIP 58662 |
14.03 |
| 2026-08-09 00:00 |
11:59:54.11 |
-69:18:53.8 |
HIP 58662 |
12.04 |
| 2026-08-09 12:00 |
12:00:11.35 |
-69:17:36.8 |
HIP 58662 |
10.06 |
| 2026-08-10 00:00 |
12:00:28.67 |
-69:16:20.6 |
HIP 58662 |
8.08 |
| 2026-08-10 12:00 |
12:00:46.06 |
-69:15:05.1 |
HIP 58662 |
6.10 |
| 2026-08-11 00:00 |
12:01:03.52 |
-69:13:50.5 |
HIP 58662 |
4.14 |
| 2026-08-11 12:00 |
12:01:21.06 |
-69:12:36.7 |
HIP 58662 |
2.21 |
| 2026-08-12 00:00 |
12:01:38.67 |
-69:11:23.7 |
HIP 58662 |
0.71 |
| 2026-08-12 12:00 |
12:01:56.35 |
-69:10:11.6 |
HIP 58662 |
1.98 |
| 2026-08-13 00:00 |
12:02:14.10 |
-69:09:00.2 |
HIP 58720 |
3.29 |
| 2026-08-13 12:00 |
12:02:31.92 |
-69:07:49.7 |
HIP 58720 |
3.74 |
| 2026-08-14 00:00 |
12:02:49.80 |
-69:06:39.9 |
HIP 58720 |
4.99 |
| 2026-08-14 12:00 |
12:03:07.76 |
-69:05:31.0 |
HIP 58720 |
6.58 |
| 2026-08-15 00:00 |
12:03:25.78 |
-69:04:23.0 |
HIP 58720 |
8.33 |
| 2026-08-15 12:00 |
12:03:43.86 |
-69:03:15.7 |
HIP 58720 |
10.16 |
| 2026-08-16 00:00 |
12:04:02.01 |
-69:02:09.3 |
HIP 58720 |
12.02 |
| 2026-08-16 12:00 |
12:04:20.22 |
-69:01:03.7 |
HIP 59030 |
11.65 |
| 2026-08-17 00:00 |
12:04:38.49 |
-68:59:59.0 |
HIP 59030 |
11.05 |
| 2026-08-17 12:00 |
12:04:56.82 |
-68:58:55.0 |
HIP 59030 |
10.75 |
| 2026-08-18 00:00 |
12:05:15.21 |
-68:57:51.9 |
HIP 59030 |
10.79 |
| 2026-08-18 12:00 |
12:05:33.66 |
-68:56:49.6 |
HIP 59030 |
11.16 |
| 2026-08-19 00:00 |
12:05:52.17 |
-68:55:48.2 |
HIP 59030 |
11.82 |