メタデータ
| 項目 |
値 |
| 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 |
値 |
| 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
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 |
値 |
| H0 |
8.336 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.501 |
| 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) |
| 2026-06-01 00:00 |
22:33:11.60 |
-01:45:47.4 |
HIP 111394 |
17.11 |
| 2026-06-01 12:00 |
22:33:12.10 |
-01:45:35.0 |
HIP 111394 |
16.88 |
| 2026-06-02 00:00 |
22:33:12.54 |
-01:45:23.1 |
HIP 111394 |
16.67 |
| 2026-06-02 12:00 |
22:33:12.92 |
-01:45:11.5 |
HIP 111394 |
16.47 |
| 2026-06-03 00:00 |
22:33:13.25 |
-01:45:00.2 |
HIP 111394 |
16.29 |
| 2026-06-03 12:00 |
22:33:13.51 |
-01:44:49.3 |
HIP 111394 |
16.12 |
| 2026-06-04 00:00 |
22:33:13.71 |
-01:44:38.7 |
HIP 111394 |
15.97 |
| 2026-06-04 12:00 |
22:33:13.86 |
-01:44:28.5 |
HIP 111394 |
15.83 |
| 2026-06-05 00:00 |
22:33:13.94 |
-01:44:18.7 |
HIP 111394 |
15.71 |
| 2026-06-05 12:00 |
22:33:13.97 |
-01:44:09.2 |
HIP 111394 |
15.61 |
| 2026-06-06 00:00 |
22:33:13.94 |
-01:44:00.1 |
HIP 111394 |
15.52 |
| 2026-06-06 12:00 |
22:33:13.85 |
-01:43:51.3 |
HIP 111394 |
15.45 |
| 2026-06-07 00:00 |
22:33:13.69 |
-01:43:42.9 |
HIP 111394 |
15.39 |
| 2026-06-07 12:00 |
22:33:13.48 |
-01:43:34.9 |
HIP 111394 |
15.36 |
| 2026-06-08 00:00 |
22:33:13.21 |
-01:43:27.2 |
HIP 111394 |
15.33 |
| 2026-06-08 12:00 |
22:33:12.88 |
-01:43:19.9 |
HIP 111394 |
15.33 |
| 2026-06-09 00:00 |
22:33:12.49 |
-01:43:12.9 |
HIP 111394 |
15.34 |
| 2026-06-09 12:00 |
22:33:12.05 |
-01:43:06.3 |
HIP 111394 |
15.37 |
| 2026-06-10 00:00 |
22:33:11.54 |
-01:43:00.1 |
HIP 111394 |
15.42 |
| 2026-06-10 12:00 |
22:33:10.97 |
-01:42:54.3 |
HIP 111394 |
15.49 |
| 2026-06-11 00:00 |
22:33:10.34 |
-01:42:48.8 |
HIP 111394 |
15.57 |
| 2026-06-11 12:00 |
22:33:09.66 |
-01:42:43.8 |
HIP 111394 |
15.67 |
| 2026-06-12 00:00 |
22:33:08.91 |
-01:42:39.0 |
HIP 111394 |
15.79 |
| 2026-06-12 12:00 |
22:33:08.10 |
-01:42:34.7 |
HIP 111394 |
15.92 |
| 2026-06-13 00:00 |
22:33:07.24 |
-01:42:30.7 |
HIP 111394 |
16.07 |
| 2026-06-13 12:00 |
22:33:06.31 |
-01:42:27.1 |
HIP 111394 |
16.25 |
| 2026-06-14 00:00 |
22:33:05.33 |
-01:42:23.9 |
HIP 111394 |
16.43 |
| 2026-06-14 12:00 |
22:33:04.29 |
-01:42:21.1 |
HIP 111394 |
16.64 |
| 2026-06-15 00:00 |
22:33:03.19 |
-01:42:18.6 |
HIP 111394 |
16.86 |
| 2026-06-15 12:00 |
22:33:02.02 |
-01:42:16.6 |
HIP 111394 |
17.10 |
| 2026-06-16 00:00 |
22:33:00.80 |
-01:42:14.9 |
HIP 111394 |
17.36 |
| 2026-06-16 12:00 |
22:32:59.53 |
-01:42:13.5 |
HIP 111394 |
17.64 |
| 2026-06-17 00:00 |
22:32:58.19 |
-01:42:12.6 |
HIP 111394 |
17.93 |
| 2026-06-17 12:00 |
22:32:56.79 |
-01:42:12.0 |
HIP 111394 |
18.25 |
| 2026-06-18 00:00 |
22:32:55.34 |
-01:42:11.9 |
HIP 111394 |
18.57 |
| 2026-06-18 12:00 |
22:32:53.82 |
-01:42:12.1 |
HIP 111394 |
18.92 |
| 2026-06-19 00:00 |
22:32:52.25 |
-01:42:12.7 |
HIP 111394 |
19.28 |
| 2026-06-19 12:00 |
22:32:50.62 |
-01:42:13.6 |
HIP 111394 |
19.66 |
| 2026-06-20 00:00 |
22:32:48.94 |
-01:42:15.0 |
HIP 111394 |
20.06 |
| 2026-06-20 12:00 |
22:32:47.19 |
-01:42:16.7 |
HIP 111394 |
20.47 |
| 2026-06-21 00:00 |
22:32:45.39 |
-01:42:18.8 |
HIP 111394 |
20.90 |
| 2026-06-21 12:00 |
22:32:43.53 |
-01:42:21.3 |
HIP 111394 |
21.35 |
| 2026-06-22 00:00 |
22:32:41.62 |
-01:42:24.2 |
HIP 111394 |
21.81 |