C/2023 A2 (SWAN)

メタデータ

項目 値
Designation C/2023 A2 (SWAN)
Type C
Perihelion (tp_cal, UTC) 2023-01-20T09:20:12.062400Z
Orbit solution date (soln_date, UTC) 2026-03-12T09:30:38Z
Obs used 159
NEO -
M1 12.800
K1 20.500
PC -
Discovery observation (MPC, UTC) 2023-01-06T00:00:00Z
Discovery magnitude (MPC) -
Discovery observatory (MPC) 249 · SOHO
オスキュレーティング軌道要素
項目 値
Epoch (epoch_cal, TDB) 2023-03-06.0000000
e 0.99829132
q (au) 0.947460
a (au) 554.499318
i (deg) 94.708355
Ω (om, deg) 94.471088
ω (w, deg) 142.583308
M (ma, deg) 0.003367

等級

C/2023 A2 (SWAN) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (14.827 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目 値
H0 14.827
n 6.000
gf 0.991
gb -1.000
k 0.840
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)
2026-09-20 00:00 06:59:44.57 -44:55:27.8 HIP 33636 19.00
2026-09-20 12:00 06:59:47.56 -44:57:19.6 HIP 33636 17.39
2026-09-21 00:00 06:59:50.45 -44:59:11.6 HIP 33636 15.83
2026-09-21 12:00 06:59:53.23 -45:01:03.8 HIP 33636 14.36
2026-09-22 00:00 06:59:55.91 -45:02:56.3 HIP 33636 13.00
2026-09-22 12:00 06:59:58.48 -45:04:49.0 HIP 33636 11.78
2026-09-23 00:00 07:00:00.95 -45:06:41.9 HIP 33636 10.76
2026-09-23 12:00 07:00:03.31 -45:08:35.1 HIP 33636 9.99
2026-09-24 00:00 07:00:05.56 -45:10:28.4 HIP 33636 9.53
2026-09-24 12:00 07:00:07.71 -45:12:22.0 HIP 33636 9.44
2026-09-25 00:00 07:00:09.74 -45:14:15.7 HIP 33636 9.71
2026-09-25 12:00 07:00:11.67 -45:16:09.6 HIP 33636 10.33
2026-09-26 00:00 07:00:13.49 -45:18:03.7 HIP 33636 11.23
2026-09-26 12:00 07:00:15.21 -45:19:58.0 HIP 33636 12.35
2026-09-27 00:00 07:00:16.81 -45:21:52.4 HIP 33636 13.64
2026-09-27 12:00 07:00:18.31 -45:23:46.9 HIP 33636 15.05
2026-09-28 00:00 07:00:19.69 -45:25:41.6 HIP 33636 16.56
2026-09-28 12:00 07:00:20.97 -45:27:36.5 HIP 33636 18.13
2026-09-29 00:00 07:00:22.13 -45:29:31.4 HIP 33636 19.76
2026-09-29 12:00 07:00:23.18 -45:31:26.5 HIP 33636 21.43
2026-09-30 00:00 07:00:24.13 -45:33:21.7 HIP 33871 21.18
2026-09-30 12:00 07:00:24.96 -45:35:17.0 HIP 33871 19.78
2026-10-01 00:00 07:00:25.67 -45:37:12.3 HIP 33871 18.49
2026-10-01 12:00 07:00:26.28 -45:39:07.8 HIP 33871 17.34
2026-10-02 00:00 07:00:26.77 -45:41:03.3 HIP 33871 16.34
2026-10-02 12:00 07:00:27.15 -45:42:58.9 HIP 33871 15.55
2026-10-03 00:00 07:00:27.42 -45:44:54.5 HIP 33871 14.98
2026-10-03 12:00 07:00:27.57 -45:46:50.2 HIP 33871 14.66
2026-10-04 00:00 07:00:27.61 -45:48:45.9 HIP 33871 14.61
2026-10-04 12:00 07:00:27.54 -45:50:41.7 HIP 33871 14.84
2026-10-05 00:00 07:00:27.34 -45:52:37.5 HIP 33871 15.32
2026-10-05 12:00 07:00:27.04 -45:54:33.2 HIP 33871 16.05
2026-10-06 00:00 07:00:26.61 -45:56:29.0 HIP 33871 16.98
2026-10-06 12:00 07:00:26.08 -45:58:24.8 HIP 33871 18.08
2026-10-07 00:00 07:00:25.42 -46:00:20.5 HIP 33619 17.86
2026-10-07 12:00 07:00:24.65 -46:02:16.2 HIP 33619 16.60
2026-10-08 00:00 07:00:23.76 -46:04:11.9 HIP 33619 15.45
2026-10-08 12:00 07:00:22.75 -46:06:07.5 HIP 33619 14.46
2026-10-09 00:00 07:00:21.63 -46:08:03.0 HIP 33619 13.66
2026-10-09 12:00 07:00:20.39 -46:09:58.5 HIP 33619 13.07
2026-10-10 00:00 07:00:19.03 -46:11:53.9 HIP 33619 12.73
2026-10-10 12:00 07:00:17.55 -46:13:49.2 HIP 33619 12.66
2026-10-11 00:00 07:00:15.95 -46:15:44.4 HIP 33619 12.87