Comet Archive

Clear skies!

C/2017 D3 (ATLAS)

メタデータ

項目
Designation C/2017 D3 (ATLAS)
Type C
Perihelion (tp_cal, UTC) 2017-04-26T17:48:37.664640Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:33:30Z
Obs used 523
NEO -
M1 11.100
K1 4.500
PC -
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 2017-10-06.0000000
e 1.00243639
q (au) 4.971286
a (au) -2040.429612
i (deg) 125.570039
Ω (om, deg) 186.618173
ω (w, deg) 340.767499
M (ma, deg) 0.001735

等級

C/2017 D3 (ATLAS) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (10.067 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 10.067
n 2.000
gf 0.999
gb -1.000
k 1.000
δ90 9.999
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)
2026-02-03 00:00 03:21:05.07 +75:22:46.9 HIP 15516 9.56
2026-02-03 12:00 03:20:59.05 +75:21:20.2 HIP 15516 8.11
2026-02-04 00:00 03:20:53.26 +75:19:53.4 HIP 15516 6.68
2026-02-04 12:00 03:20:47.68 +75:18:26.8 HIP 15516 5.29
2026-02-05 00:00 03:20:42.33 +75:17:00.2 HIP 15516 3.99
2026-02-05 12:00 03:20:37.19 +75:15:33.7 HIP 15516 2.88
2026-02-06 00:00 03:20:32.27 +75:14:07.3 HIP 15516 2.26
2026-02-06 12:00 03:20:27.57 +75:12:41.0 HIP 15516 2.51
2026-02-07 00:00 03:20:23.09 +75:11:14.8 HIP 15516 3.44
2026-02-07 12:00 03:20:18.82 +75:09:48.7 HIP 15516 4.66
2026-02-08 00:00 03:20:14.76 +75:08:22.7 HIP 15516 5.99
2026-02-08 12:00 03:20:10.92 +75:06:56.8 HIP 15516 7.36
2026-02-09 00:00 03:20:07.28 +75:05:31.1 HIP 15516 8.76
2026-02-09 12:00 03:20:03.86 +75:04:05.5 HIP 15516 10.17
2026-02-10 00:00 03:20:00.65 +75:02:40.0 HIP 15516 11.59
2026-02-10 12:00 03:19:57.65 +75:01:14.7 HIP 15516 13.01
2026-02-11 00:00 03:19:54.85 +74:59:49.5 HIP 15516 14.43
2026-02-11 12:00 03:19:52.26 +74:58:24.5 HIP 15516 15.85
2026-02-12 00:00 03:19:49.87 +74:56:59.7 HIP 15516 17.26
2026-02-12 12:00 03:19:47.69 +74:55:35.0 HIP 15516 18.68
2026-02-13 00:00 03:19:45.71 +74:54:10.6 HIP 15516 20.09
2026-02-13 12:00 03:19:43.93 +74:52:46.3 HIP 15516 21.50
2026-02-14 00:00 03:19:42.35 +74:51:22.2 HIP 15516 22.90
2026-02-14 12:00 03:19:40.98 +74:49:58.3 HIP 15516 24.30
2026-02-15 00:00 03:19:39.80 +74:48:34.6 HIP 15516 25.70
2026-02-15 12:00 03:19:38.81 +74:47:11.1 HIP 15516 27.09
2026-02-16 00:00 03:19:38.03 +74:45:47.9 HIP 15516 28.48
2026-02-16 12:00 03:19:37.43 +74:44:24.8 HIP 14948 29.58
2026-02-17 00:00 03:19:37.03 +74:43:02.0 HIP 14948 30.15
2026-02-17 12:00 03:19:36.83 +74:41:39.4 HIP 14948 30.78
2026-02-18 00:00 03:19:36.81 +74:40:17.1 HIP 14948 31.47
2026-02-18 12:00 03:19:36.98 +74:38:55.0 HIP 14948 32.21
2026-02-19 00:00 03:19:37.34 +74:37:33.2 HIP 15073 31.44
2026-02-19 12:00 03:19:37.89 +74:36:11.6 HIP 15073 30.50
2026-02-20 00:00 03:19:38.63 +74:34:50.3 HIP 15073 29.60
2026-02-20 12:00 03:19:39.54 +74:33:29.3 HIP 15073 28.75
2026-02-21 00:00 03:19:40.65 +74:32:08.5 HIP 15073 27.96
2026-02-21 12:00 03:19:41.93 +74:30:48.0 HIP 15843 27.09
2026-02-22 00:00 03:19:43.39 +74:29:27.8 HIP 15843 26.03
2026-02-22 12:00 03:19:45.03 +74:28:07.9 HIP 15843 25.00
2026-02-23 00:00 03:19:46.85 +74:26:48.3 HIP 15843 23.99
2026-02-23 12:00 03:19:48.85 +74:25:29.0 HIP 15843 23.01
2026-02-24 00:00 03:19:51.02 +74:24:10.0 HIP 15843 22.05