C/2025 N2 (ATLAS)

メタデータ

項目 値
Designation C/2025 N2 (ATLAS)
Type C
Perihelion (tp_cal, UTC) 2024-12-12T18:30:52.908480Z
Orbit solution date (soln_date, UTC) 2026-07-06T12:12:27Z
Obs used 49
NEO -
M1 6.400
K1 8.500
PC -
Discovery observation (MPC, UTC) 2025-07-02T01:33:05.932800Z
Discovery magnitude (MPC) 19.61 c
Discovery observatory (MPC) M22 · ATLAS South Africa, Sutherland
オスキュレーティング軌道要素
項目 値
Epoch (epoch_cal, TDB) 2025-07-27.0000000
e 1.00220626
q (au) 8.984848
a (au) -4072.429280
i (deg) 81.664420
Ω (om, deg) 94.462885
ω (w, deg) 230.115528
M (ma, deg) 0.000858

等級

C/2025 N2 (ATLAS) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (-0.838 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目 値
H0 -0.838
n 6.000
gf 1.000
gb -0.502
k 1.000
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 05:18:09.92 -73:31:43.8 HIP 24507 12.21
2026-09-20 12:00 05:18:08.11 -73:33:26.0 HIP 24507 11.69
2026-09-21 00:00 05:18:05.92 -73:35:07.9 HIP 24507 11.38
2026-09-21 12:00 05:18:03.36 -73:36:49.6 HIP 24507 11.29
2026-09-22 00:00 05:18:00.43 -73:38:31.0 HIP 24507 11.43
2026-09-22 12:00 05:17:57.11 -73:40:12.0 HIP 24507 11.79
2026-09-23 00:00 05:17:53.43 -73:41:52.8 HIP 24507 12.35
2026-09-23 12:00 05:17:49.36 -73:43:33.3 HIP 24507 13.09
2026-09-24 00:00 05:17:44.92 -73:45:13.4 HIP 24507 13.97
2026-09-24 12:00 05:17:40.10 -73:46:53.2 HIP 24507 14.97
2026-09-25 00:00 05:17:34.90 -73:48:32.6 HIP 24739 15.51
2026-09-25 12:00 05:17:29.31 -73:50:11.6 HIP 24739 13.98
2026-09-26 00:00 05:17:23.35 -73:51:50.3 HIP 24739 12.51
2026-09-26 12:00 05:17:17.00 -73:53:28.5 HIP 24739 11.12
2026-09-27 00:00 05:17:10.26 -73:55:06.3 HIP 24739 9.85
2026-09-27 12:00 05:17:03.15 -73:56:43.7 HIP 24739 8.74
2026-09-28 00:00 05:16:55.64 -73:58:20.6 HIP 24739 7.87
2026-09-28 12:00 05:16:47.75 -73:59:57.1 HIP 24739 7.31
2026-09-29 00:00 05:16:39.47 -74:01:33.1 HIP 24739 7.16
2026-09-29 12:00 05:16:30.80 -74:03:08.6 HIP 24739 7.42
2026-09-30 00:00 05:16:21.75 -74:04:43.7 HIP 24739 8.07
2026-09-30 12:00 05:16:12.30 -74:06:18.1 HIP 24739 9.02
2026-10-01 00:00 05:16:02.46 -74:07:52.1 HIP 24739 10.19
2026-10-01 12:00 05:15:52.23 -74:09:25.5 HIP 24739 11.51
2026-10-02 00:00 05:15:41.61 -74:10:58.4 HIP 24739 12.93
2026-10-02 12:00 05:15:30.60 -74:12:30.6 HIP 24739 14.43
2026-10-03 00:00 05:15:19.19 -74:14:02.3 HIP 24739 15.99
2026-10-03 12:00 05:15:07.39 -74:15:33.3 HIP 24739 17.59
2026-10-04 00:00 05:14:55.19 -74:17:03.7 HIP 24739 19.22
2026-10-04 12:00 05:14:42.60 -74:18:33.5 HIP 24739 20.87
2026-10-05 00:00 05:14:29.61 -74:20:02.6 HIP 24739 22.54
2026-10-05 12:00 05:14:16.23 -74:21:31.1 HIP 24739 24.23
2026-10-06 00:00 05:14:02.45 -74:22:58.8 HIP 24737 25.34
2026-10-06 12:00 05:13:48.27 -74:24:25.8 HIP 24737 24.94
2026-10-07 00:00 05:13:33.70 -74:25:52.1 HIP 24737 24.67
2026-10-07 12:00 05:13:18.74 -74:27:17.6 HIP 24737 24.55
2026-10-08 00:00 05:13:03.38 -74:28:42.4 HIP 24737 24.58
2026-10-08 12:00 05:12:47.62 -74:30:06.3 HIP 24737 24.76
2026-10-09 00:00 05:12:31.47 -74:31:29.5 HIP 24737 25.09
2026-10-09 12:00 05:12:14.93 -74:32:51.8 HIP 24737 25.56
2026-10-10 00:00 05:11:57.99 -74:34:13.3 HIP 24737 26.16
2026-10-10 12:00 05:11:40.66 -74:35:34.0 HIP 24737 26.90
2026-10-11 00:00 05:11:22.94 -74:36:53.8 HIP 24737 27.75