Comet Archive

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221P/LINEAR

メタデータ

項目
Designation 221P/LINEAR
Type P
Perihelion (tp_cal, UTC) 2009-01-24T08:32:46.219200Z
Orbit solution date (soln_date, UTC) 2022-10-28T22:13:13Z
Obs used 627
NEO -
M1 14.000
K1 13.250
PC 0.030
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 2011-08-08.0000000
e 0.48757555
q (au) 1.779766
a (au) 3.473226
i (deg) 11.431021
Ω (om, deg) 229.989314
ω (w, deg) 39.511181
M (ma, deg) 140.944591

等級

221P/LINEAR · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (12.562 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 12.562
n 6.000
gf 1.000
gb -0.891
k 0.999
δ90 9.995
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 06:52:58.95 +11:10:02.4 HIP 33082 11.73
2026-02-03 12:00 06:52:41.94 +11:10:57.1 HIP 33082 14.92
2026-02-04 00:00 06:52:25.09 +11:11:52.1 HIP 33082 18.52
2026-02-04 12:00 06:52:08.41 +11:12:47.4 HIP 33082 22.31
2026-02-05 00:00 06:51:51.90 +11:13:43.1 HIP 32962 25.71
2026-02-05 12:00 06:51:35.56 +11:14:39.0 HIP 32962 27.08
2026-02-06 00:00 06:51:19.40 +11:15:35.3 HIP 32858 25.01
2026-02-06 12:00 06:51:03.42 +11:16:32.0 HIP 32858 23.41
2026-02-07 00:00 06:50:47.61 +11:17:28.9 HIP 32858 22.41
2026-02-07 12:00 06:50:31.99 +11:18:26.1 HIP 32858 22.09
2026-02-08 00:00 06:50:16.55 +11:19:23.6 HIP 32858 22.44
2026-02-08 12:00 06:50:01.29 +11:20:21.4 HIP 32858 23.42
2026-02-09 00:00 06:49:46.23 +11:21:19.4 HIP 32858 24.92
2026-02-09 12:00 06:49:31.35 +11:22:17.8 HIP 32595 23.36
2026-02-10 00:00 06:49:16.67 +11:23:16.3 HIP 32595 19.63
2026-02-10 12:00 06:49:02.18 +11:24:15.1 HIP 32595 15.95
2026-02-11 00:00 06:48:47.88 +11:25:14.2 HIP 32595 12.31
2026-02-11 12:00 06:48:33.79 +11:26:13.5 HIP 32595 8.72
2026-02-12 00:00 06:48:19.89 +11:27:13.0 HIP 32595 5.18
2026-02-12 12:00 06:48:06.20 +11:28:12.7 HIP 32595 1.69
2026-02-13 00:00 06:47:52.70 +11:29:12.7 HIP 32595 1.81
2026-02-13 12:00 06:47:39.42 +11:30:12.8 HIP 32595 5.20
2026-02-14 00:00 06:47:26.34 +11:31:13.1 HIP 32595 8.55
2026-02-14 12:00 06:47:13.47 +11:32:13.6 HIP 32595 11.86
2026-02-15 00:00 06:47:00.81 +11:33:14.3 HIP 32595 15.12
2026-02-15 12:00 06:46:48.36 +11:34:15.1 HIP 32595 18.33
2026-02-16 00:00 06:46:36.12 +11:35:16.1 HIP 32595 21.49
2026-02-16 12:00 06:46:24.10 +11:36:17.2 HIP 32595 24.61
2026-02-17 00:00 06:46:12.30 +11:37:18.5 HIP 32595 27.67
2026-02-17 12:00 06:46:00.71 +11:38:19.9 HIP 32595 30.68
2026-02-18 00:00 06:45:49.34 +11:39:21.4 HIP 32247 28.06
2026-02-18 12:00 06:45:38.19 +11:40:23.0 HIP 32247 25.16
2026-02-19 00:00 06:45:27.27 +11:41:24.7 HIP 32247 22.33
2026-02-19 12:00 06:45:16.56 +11:42:26.5 HIP 32247 19.55
2026-02-20 00:00 06:45:06.08 +11:43:28.4 HIP 32247 16.84
2026-02-20 12:00 06:44:55.83 +11:44:30.4 HIP 32247 14.20
2026-02-21 00:00 06:44:45.80 +11:45:32.5 HIP 32247 11.65
2026-02-21 12:00 06:44:35.99 +11:46:34.6 HIP 32247 9.23
2026-02-22 00:00 06:44:26.42 +11:47:36.7 HIP 32247 7.01
2026-02-22 12:00 06:44:17.07 +11:48:38.9 HIP 32247 5.16
2026-02-23 00:00 06:44:07.95 +11:49:41.2 HIP 32247 4.12
2026-02-23 12:00 06:43:59.06 +11:50:43.5 HIP 32247 4.42
2026-02-24 00:00 06:43:50.40 +11:51:45.7 HIP 32247 5.78