C/2012 X1 (LINEAR)

メタデータ

項目
Designation C/2012 X1 (LINEAR)
Type C
Perihelion (tp_cal, UTC) 2014-02-21T15:12:12.525120Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:32:29Z
Obs used 2560
NEO -
M1 5.500
K1 14.250
PC 0.030
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 2013-12-18.0000000
e 0.98957208
q (au) 1.598910
a (au) 153.329748
i (deg) 44.367326
Ω (om, deg) 113.146428
ω (w, deg) 132.113677
M (ma, deg) 359.965929

等級

C/2012 X1 (LINEAR) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (7.004 + 5.465\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 7.004
n 5.465
gf 1.000
gb -0.669
k 0.933
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
2012-12-08 2013-11-20 +5.9231 -3.732
2013-11-20 2014-02-20 +6.3519 -2.844
2014-02-22 2015-12-09 +1.6210 -2.089

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 03:47:06.38 -23:22:02.1 HIP 17651 7.96
2026-07-29 12:00 03:47:08.29 -23:22:35.4 HIP 17651 8.65
2026-07-30 00:00 03:47:10.16 -23:23:09.0 HIP 17651 9.34
2026-07-30 12:00 03:47:12.00 -23:23:42.7 HIP 17651 10.04
2026-07-31 00:00 03:47:13.81 -23:24:16.8 HIP 17651 10.74
2026-07-31 12:00 03:47:15.59 -23:24:51.0 HIP 17651 11.43
2026-08-01 00:00 03:47:17.33 -23:25:25.4 HIP 17651 12.13
2026-08-01 12:00 03:47:19.03 -23:26:00.1 HIP 17651 12.83
2026-08-02 00:00 03:47:20.71 -23:26:34.9 HIP 17651 13.52
2026-08-02 12:00 03:47:22.34 -23:27:10.0 HIP 17651 14.22
2026-08-03 00:00 03:47:23.95 -23:27:45.3 HIP 17651 14.91
2026-08-03 12:00 03:47:25.52 -23:28:20.8 HIP 17651 15.60
2026-08-04 00:00 03:47:27.05 -23:28:56.4 HIP 17651 16.29
2026-08-04 12:00 03:47:28.55 -23:29:32.3 HIP 17651 16.98
2026-08-05 00:00 03:47:30.02 -23:30:08.4 HIP 17651 17.67
2026-08-05 12:00 03:47:31.45 -23:30:44.7 HIP 17651 18.36
2026-08-06 00:00 03:47:32.85 -23:31:21.2 HIP 17651 19.05
2026-08-06 12:00 03:47:34.21 -23:31:57.8 HIP 17651 19.73
2026-08-07 00:00 03:47:35.53 -23:32:34.7 HIP 17717 19.93
2026-08-07 12:00 03:47:36.82 -23:33:11.7 HIP 17717 19.30
2026-08-08 00:00 03:47:38.07 -23:33:49.0 HIP 17717 18.68
2026-08-08 12:00 03:47:39.29 -23:34:26.4 HIP 17717 18.05
2026-08-09 00:00 03:47:40.47 -23:35:03.9 HIP 17717 17.42
2026-08-09 12:00 03:47:41.62 -23:35:41.7 HIP 17717 16.80
2026-08-10 00:00 03:47:42.73 -23:36:19.6 HIP 17717 16.18
2026-08-10 12:00 03:47:43.80 -23:36:57.8 HIP 17717 15.55
2026-08-11 00:00 03:47:44.84 -23:37:36.0 HIP 17717 14.94
2026-08-11 12:00 03:47:45.84 -23:38:14.5 HIP 17717 14.32
2026-08-12 00:00 03:47:46.80 -23:38:53.1 HIP 17717 13.70
2026-08-12 12:00 03:47:47.73 -23:39:31.8 HIP 17717 13.09
2026-08-13 00:00 03:47:48.62 -23:40:10.7 HIP 17717 12.48
2026-08-13 12:00 03:47:49.47 -23:40:49.8 HIP 17717 11.87
2026-08-14 00:00 03:47:50.29 -23:41:29.0 HIP 17717 11.27
2026-08-14 12:00 03:47:51.07 -23:42:08.4 HIP 17717 10.67
2026-08-15 00:00 03:47:51.81 -23:42:47.9 HIP 17717 10.08
2026-08-15 12:00 03:47:52.51 -23:43:27.5 HIP 17717 9.50
2026-08-16 00:00 03:47:53.18 -23:44:07.3 HIP 17717 8.92
2026-08-16 12:00 03:47:53.81 -23:44:47.2 HIP 17717 8.36
2026-08-17 00:00 03:47:54.40 -23:45:27.3 HIP 17717 7.80
2026-08-17 12:00 03:47:54.96 -23:46:07.4 HIP 17717 7.27
2026-08-18 00:00 03:47:55.48 -23:46:47.7 HIP 17717 6.75
2026-08-18 12:00 03:47:55.96 -23:47:28.2 HIP 17717 6.26
2026-08-19 00:00 03:47:56.40 -23:48:08.7 HIP 17717 5.80