C/2012 T4 (McNaught)

メタデータ

項目
Designation C/2012 T4 (McNaught)
Type C
Perihelion (tp_cal, UTC) 2012-10-10T22:22:44.699520Z
Orbit solution date (soln_date, UTC) 2022-06-07T21:44:03Z
Obs used 49
NEO -
M1 15.500
K1 6.250
PC 0.030
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 2012-10-18.0000000
e 0.99118923
q (au) 1.955997
a (au) 222.000586
i (deg) 24.085273
Ω (om, deg) 99.368559
ω (w, deg) 219.915260
M (ma, deg) 0.002106

等級

C/2012 T4 (McNaught) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (14.048 + 4.167\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 14.048
n 4.167
gf 1.000
gb -1.000
k 0.990
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

天体暦

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-05-12 00:00 07:20:27.18 +26:39:59.6 HIP 35639 14.96
2026-05-12 12:00 07:20:29.75 +26:39:52.6 HIP 35639 14.47
2026-05-13 00:00 07:20:32.36 +26:39:45.5 HIP 35639 13.97
2026-05-13 12:00 07:20:34.99 +26:39:38.4 HIP 35639 13.48
2026-05-14 00:00 07:20:37.66 +26:39:31.2 HIP 35639 13.00
2026-05-14 12:00 07:20:40.35 +26:39:24.1 HIP 35639 12.52
2026-05-15 00:00 07:20:43.07 +26:39:16.9 HIP 35639 12.05
2026-05-15 12:00 07:20:45.82 +26:39:09.6 HIP 35639 11.60
2026-05-16 00:00 07:20:48.60 +26:39:02.4 HIP 35639 11.15
2026-05-16 12:00 07:20:51.40 +26:38:55.1 HIP 35639 10.72
2026-05-17 00:00 07:20:54.24 +26:38:47.7 HIP 35639 10.30
2026-05-17 12:00 07:20:57.10 +26:38:40.4 HIP 35639 9.91
2026-05-18 00:00 07:20:59.98 +26:38:33.0 HIP 35639 9.54
2026-05-18 12:00 07:21:02.90 +26:38:25.6 HIP 35639 9.21
2026-05-19 00:00 07:21:05.84 +26:38:18.1 HIP 35639 8.91
2026-05-19 12:00 07:21:08.81 +26:38:10.7 HIP 35639 8.65
2026-05-20 00:00 07:21:11.80 +26:38:03.2 HIP 35639 8.43
2026-05-20 12:00 07:21:14.82 +26:37:55.6 HIP 35639 8.26
2026-05-21 00:00 07:21:17.87 +26:37:48.1 HIP 35639 8.15
2026-05-21 12:00 07:21:20.94 +26:37:40.5 HIP 35639 8.10
2026-05-22 00:00 07:21:24.03 +26:37:32.9 HIP 35639 8.11
2026-05-22 12:00 07:21:27.15 +26:37:25.3 HIP 35639 8.18
2026-05-23 00:00 07:21:30.30 +26:37:17.6 HIP 35639 8.31
2026-05-23 12:00 07:21:33.47 +26:37:09.9 HIP 35639 8.50
2026-05-24 00:00 07:21:36.67 +26:37:02.2 HIP 35639 8.75
2026-05-24 12:00 07:21:39.89 +26:36:54.5 HIP 35639 9.06
2026-05-25 00:00 07:21:43.13 +26:36:46.8 HIP 35639 9.41
2026-05-25 12:00 07:21:46.40 +26:36:39.0 HIP 35639 9.81
2026-05-26 00:00 07:21:49.69 +26:36:31.2 HIP 35639 10.25
2026-05-26 12:00 07:21:53.00 +26:36:23.4 HIP 35639 10.74
2026-05-27 00:00 07:21:56.34 +26:36:15.6 HIP 35639 11.25
2026-05-27 12:00 07:21:59.70 +26:36:07.8 HIP 35639 11.79
2026-05-28 00:00 07:22:03.08 +26:35:59.9 HIP 35639 12.37
2026-05-28 12:00 07:22:06.48 +26:35:52.0 HIP 35639 12.96
2026-05-29 00:00 07:22:09.91 +26:35:44.1 HIP 35639 13.58
2026-05-29 12:00 07:22:13.36 +26:35:36.2 HIP 35639 14.22
2026-05-30 00:00 07:22:16.83 +26:35:28.3 HIP 35639 14.88
2026-05-30 12:00 07:22:20.32 +26:35:20.3 HIP 35639 15.55
2026-05-31 00:00 07:22:23.83 +26:35:12.4 HIP 35639 16.24
2026-05-31 12:00 07:22:27.37 +26:35:04.4 HIP 35639 16.94
2026-06-01 00:00 07:22:30.92 +26:34:56.4 HIP 35639 17.66
2026-06-01 12:00 07:22:34.50 +26:34:48.4 HIP 35639 18.38
2026-06-02 00:00 07:22:38.09 +26:34:40.4 HIP 35639 19.12