C/2012 Y3 (McNaught)

メタデータ

項目
Designation C/2012 Y3 (McNaught)
Type C
Perihelion (tp_cal, UTC) 2012-08-25T20:18:44.000640Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:32:30Z
Obs used 150
NEO -
M1 12.900
K1 4.500
PC -
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 2013-02-01.0000000
e 0.93994217
q (au) 1.764843
a (au) 29.385733
i (deg) 73.231907
Ω (om, deg) 122.707962
ω (w, deg) 235.694296
M (ma, deg) 0.984727

等級

C/2012 Y3 (McNaught) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (11.507 + 5.732\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 11.507
n 5.732
gf 0.994
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

天体暦

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-05-12 00:00 09:44:17.41 +48:06:08.7 HIP 47633 25.20
2026-05-12 12:00 09:44:17.40 +48:05:35.9 HIP 47633 25.63
2026-05-13 00:00 09:44:17.44 +48:05:02.9 HIP 47633 26.07
2026-05-13 12:00 09:44:17.54 +48:04:29.8 HIP 47633 26.52
2026-05-14 00:00 09:44:17.68 +48:03:56.6 HIP 47633 26.99
2026-05-14 12:00 09:44:17.88 +48:03:23.3 HIP 47633 27.46
2026-05-15 00:00 09:44:18.13 +48:02:49.8 HIP 47633 27.94
2026-05-15 12:00 09:44:18.44 +48:02:16.1 HIP 47633 28.44
2026-05-16 00:00 09:44:18.79 +48:01:42.4 HIP 47633 28.94
2026-05-16 12:00 09:44:19.20 +48:01:08.5 HIP 47633 29.45
2026-05-17 00:00 09:44:19.67 +48:00:34.5 HIP 48013 29.56
2026-05-17 12:00 09:44:20.18 +48:00:00.3 HIP 48013 29.51
2026-05-18 00:00 09:44:20.74 +47:59:26.1 HIP 48013 29.46
2026-05-18 12:00 09:44:21.36 +47:58:51.7 HIP 48013 29.42
2026-05-19 00:00 09:44:22.03 +47:58:17.3 HIP 48013 29.38
2026-05-19 12:00 09:44:22.75 +47:57:42.7 HIP 48013 29.35
2026-05-20 00:00 09:44:23.53 +47:57:08.0 HIP 48013 29.31
2026-05-20 12:00 09:44:24.35 +47:56:33.2 HIP 48013 29.28
2026-05-21 00:00 09:44:25.22 +47:55:58.3 HIP 48013 29.26
2026-05-21 12:00 09:44:26.15 +47:55:23.4 HIP 48013 29.24
2026-05-22 00:00 09:44:27.13 +47:54:48.3 HIP 48013 29.22
2026-05-22 12:00 09:44:28.16 +47:54:13.1 HIP 48013 29.21
2026-05-23 00:00 09:44:29.23 +47:53:37.9 HIP 48013 29.20
2026-05-23 12:00 09:44:30.36 +47:53:02.6 HIP 48013 29.20
2026-05-24 00:00 09:44:31.54 +47:52:27.1 HIP 48013 29.21
2026-05-24 12:00 09:44:32.77 +47:51:51.6 HIP 48013 29.22
2026-05-25 00:00 09:44:34.05 +47:51:16.1 HIP 48013 29.23
2026-05-25 12:00 09:44:35.38 +47:50:40.4 HIP 48013 29.26
2026-05-26 00:00 09:44:36.75 +47:50:04.7 HIP 47618 29.09
2026-05-26 12:00 09:44:38.18 +47:49:28.9 HIP 47618 28.85
2026-05-27 00:00 09:44:39.66 +47:48:53.1 HIP 47618 28.62
2026-05-27 12:00 09:44:41.18 +47:48:17.2 HIP 47618 28.41
2026-05-28 00:00 09:44:42.76 +47:47:41.2 HIP 47618 28.22
2026-05-28 12:00 09:44:44.38 +47:47:05.2 HIP 47618 28.05
2026-05-29 00:00 09:44:46.05 +47:46:29.1 HIP 47618 27.90
2026-05-29 12:00 09:44:47.77 +47:45:52.9 HIP 47618 27.77
2026-05-30 00:00 09:44:49.53 +47:45:16.7 HIP 47618 27.66
2026-05-30 12:00 09:44:51.35 +47:44:40.5 HIP 47618 27.57
2026-05-31 00:00 09:44:53.21 +47:44:04.2 HIP 47618 27.51
2026-05-31 12:00 09:44:55.12 +47:43:27.9 HIP 47618 27.47
2026-06-01 00:00 09:44:57.08 +47:42:51.5 HIP 47618 27.46
2026-06-01 12:00 09:44:59.08 +47:42:15.1 HIP 47618 27.47
2026-06-02 00:00 09:45:01.13 +47:41:38.7 HIP 47618 27.50