Comet Archive

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C/2019 F2 (ATLAS)

メタデータ

項目
Designation C/2019 F2 (ATLAS)
Type C
Perihelion (tp_cal, UTC) 2019-09-08T21:26:06.544320Z
Orbit solution date (soln_date, UTC) 2025-09-09T12:42:31Z
Obs used 683
NEO -
M1 5.300
K1 24.000
PC 0.030
Discovery observation (MPC, UTC) 2019-03-26T07:21:56.332800Z
Discovery magnitude (MPC) 17.58 o
Discovery observatory (MPC) T08 · ATLAS-MLO, Mauna Loa
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 2019-05-07.0000000
e 0.86507120
q (au) 2.232882
a (au) 16.548594
i (deg) 19.188643
Ω (om, deg) 175.867930
ω (w, deg) 10.953986
M (ma, deg) 358.171475

等級

C/2019 F2 (ATLAS) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (8.336 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 8.336
n 6.000
gf 1.000
gb -0.500
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

残差 (区間線形)

$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$

開始日 (UTC) 終了日 (UTC) a b
2019-02-26 2019-04-23 +11.7951 -5.190
2019-04-23 2019-06-26 +19.2752 -8.502
2019-12-28 2020-07-20 +5.9715 -2.763

log10 r = log10(太陽距離/AU)、Δ = 地球距離(AU)

天体暦

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-02-03 00:00 22:10:55.00 -04:03:48.7 HIP 109442 13.23
2026-02-03 12:00 22:11:02.83 -04:03:13.6 HIP 109442 14.15
2026-02-04 00:00 22:11:10.68 -04:02:38.4 HIP 109442 15.30
2026-02-04 12:00 22:11:18.54 -04:02:03.0 HIP 109442 16.61
2026-02-05 00:00 22:11:26.41 -04:01:27.3 HIP 109442 18.07
2026-02-05 12:00 22:11:34.29 -04:00:51.5 HIP 109442 19.63
2026-02-06 00:00 22:11:42.19 -04:00:15.5 HIP 109442 21.28
2026-02-06 12:00 22:11:50.09 -03:59:39.2 HIP 109698 21.74
2026-02-07 00:00 22:11:58.00 -03:59:02.8 HIP 109698 19.68
2026-02-07 12:00 22:12:05.93 -03:58:26.3 HIP 109698 17.61
2026-02-08 00:00 22:12:13.86 -03:57:49.5 HIP 109698 15.54
2026-02-08 12:00 22:12:21.80 -03:57:12.6 HIP 109698 13.47
2026-02-09 00:00 22:12:29.75 -03:56:35.4 HIP 109698 11.40
2026-02-09 12:00 22:12:37.71 -03:55:58.1 HIP 109698 9.33
2026-02-10 00:00 22:12:45.67 -03:55:20.7 HIP 109698 7.26
2026-02-10 12:00 22:12:53.65 -03:54:43.0 HIP 109698 5.20
2026-02-11 00:00 22:13:01.62 -03:54:05.2 HIP 109698 3.16
2026-02-11 12:00 22:13:09.61 -03:53:27.3 HIP 109698 1.28
2026-02-12 00:00 22:13:17.60 -03:52:49.1 HIP 109698 1.43
2026-02-12 12:00 22:13:25.60 -03:52:10.8 HIP 109698 3.35
2026-02-13 00:00 22:13:33.60 -03:51:32.4 HIP 109698 5.40
2026-02-13 12:00 22:13:41.60 -03:50:53.8 HIP 109733 4.36
2026-02-14 00:00 22:13:49.61 -03:50:15.0 HIP 109733 4.14
2026-02-14 12:00 22:13:57.62 -03:49:36.1 HIP 109733 4.91
2026-02-15 00:00 22:14:05.64 -03:48:57.0 HIP 109733 6.32
2026-02-15 12:00 22:14:13.66 -03:48:17.8 HIP 109733 8.04
2026-02-16 00:00 22:14:21.68 -03:47:38.5 HIP 109733 9.91
2026-02-16 12:00 22:14:29.70 -03:46:59.0 HIP 109733 11.85
2026-02-17 00:00 22:14:37.72 -03:46:19.4 HIP 109733 13.85
2026-02-17 12:00 22:14:45.75 -03:45:39.6 HIP 109733 15.87
2026-02-18 00:00 22:14:53.77 -03:44:59.7 HIP 109733 17.92
2026-02-18 12:00 22:15:01.79 -03:44:19.7 HIP 109733 19.97
2026-02-19 00:00 22:15:09.82 -03:43:39.6 HIP 109733 22.04
2026-02-19 12:00 22:15:17.84 -03:42:59.3 HIP 109733 24.12
2026-02-20 00:00 22:15:25.86 -03:42:18.9 HIP 109733 26.20
2026-02-20 12:00 22:15:33.88 -03:41:38.4 HIP 109733 28.28
2026-02-21 00:00 22:15:41.89 -03:40:57.8 HIP 109733 30.37
2026-02-21 12:00 22:15:49.90 -03:40:17.1 HIP 109733 32.46
2026-02-22 00:00 22:15:57.91 -03:39:36.3 HIP 109733 34.56
2026-02-22 12:00 22:16:05.92 -03:38:55.3 HIP 109733 36.65
2026-02-23 00:00 22:16:13.92 -03:38:14.3 HIP 109733 38.75
2026-02-23 12:00 22:16:21.92 -03:37:33.2 HIP 110106 38.86
2026-02-24 00:00 22:16:29.91 -03:36:51.9 HIP 110106 36.97