C/2021 F1 (Lemmon-PANSTARRS)

メタデータ

項目
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
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

C/2021 F1 (Lemmon-PANSTARRS) · Magnitude (Full range)

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
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)
2026-03-26 00:00 12:36:07.70 -77:34:18.7 HIP 61183 14.88
2026-03-26 12:00 12:35:29.35 -77:33:57.8 HIP 61183 13.38
2026-03-27 00:00 12:34:51.02 -77:33:35.5 HIP 61183 12.07
2026-03-27 12:00 12:34:12.70 -77:33:11.6 HIP 61183 11.03
2026-03-28 00:00 12:33:34.41 -77:32:46.3 HIP 61183 10.33
2026-03-28 12:00 12:32:56.14 -77:32:19.5 HIP 61183 10.05
2026-03-29 00:00 12:32:17.92 -77:31:51.1 HIP 61183 10.23
2026-03-29 12:00 12:31:39.74 -77:31:21.4 HIP 61183 10.84
2026-03-30 00:00 12:31:01.61 -77:30:50.1 HIP 61183 11.83
2026-03-30 12:00 12:30:23.53 -77:30:17.3 HIP 61183 13.11
2026-03-31 00:00 12:29:45.52 -77:29:43.1 HIP 61183 14.61
2026-03-31 12:00 12:29:07.58 -77:29:07.4 HIP 61183 16.26
2026-04-01 00:00 12:28:29.71 -77:28:30.2 HIP 61183 18.03
2026-04-01 12:00 12:27:51.93 -77:27:51.6 HIP 60526 18.68
2026-04-02 00:00 12:27:14.23 -77:27:11.5 HIP 60526 16.96
2026-04-02 12:00 12:26:36.62 -77:26:29.9 HIP 60526 15.33
2026-04-03 00:00 12:25:59.11 -77:25:46.9 HIP 60526 13.83
2026-04-03 12:00 12:25:21.71 -77:25:02.5 HIP 60526 12.51
2026-04-04 00:00 12:24:44.42 -77:24:16.6 HIP 60526 11.43
2026-04-04 12:00 12:24:07.24 -77:23:29.2 HIP 60526 10.67
2026-04-05 00:00 12:23:30.19 -77:22:40.4 HIP 60526 10.30
2026-04-05 12:00 12:22:53.27 -77:21:50.2 HIP 60526 10.37
2026-04-06 00:00 12:22:16.48 -77:20:58.5 HIP 60526 10.87
2026-04-06 12:00 12:21:39.83 -77:20:05.5 HIP 60526 11.74
2026-04-07 00:00 12:21:03.32 -77:19:11.0 HIP 60526 12.93
2026-04-07 12:00 12:20:26.96 -77:18:15.1 HIP 60526 14.34
2026-04-08 00:00 12:19:50.76 -77:17:17.8 HIP 60526 15.93
2026-04-08 12:00 12:19:14.73 -77:16:19.1 HIP 60526 17.64
2026-04-09 00:00 12:18:38.85 -77:15:19.0 HIP 60526 19.45
2026-04-09 12:00 12:18:03.16 -77:14:17.5 HIP 60526 21.33
2026-04-10 00:00 12:17:27.63 -77:13:14.6 HIP 60526 23.26
2026-04-10 12:00 12:16:52.29 -77:12:10.4 HIP 60526 25.24
2026-04-11 00:00 12:16:17.14 -77:11:04.8 HIP 60119 25.85
2026-04-11 12:00 12:15:42.18 -77:09:57.8 HIP 60119 25.85
2026-04-12 00:00 12:15:07.41 -77:08:49.5 HIP 60119 26.03
2026-04-12 12:00 12:14:32.85 -77:07:39.9 HIP 60119 26.38
2026-04-13 00:00 12:13:58.50 -77:06:28.9 HIP 60119 26.90
2026-04-13 12:00 12:13:24.35 -77:05:16.6 HIP 60119 27.58
2026-04-14 00:00 12:12:50.43 -77:04:03.0 HIP 60119 28.41
2026-04-14 12:00 12:12:16.72 -77:02:48.1 HIP 59245 26.72
2026-04-15 00:00 12:11:43.24 -77:01:31.8 HIP 59245 24.84
2026-04-15 12:00 12:11:09.99 -77:00:14.3 HIP 59245 23.00
2026-04-16 00:00 12:10:36.97 -76:58:55.5 HIP 59245 21.24