C/2019 A9 (PANSTARRS)
メタデータ
| 項目 |
値 |
| Designation |
C/2019 A9 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2019-07-26T12:36:17.003520Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:51Z |
| Obs used |
199 |
| NEO |
- |
| M1 |
10.300 |
| K1 |
17.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2019-01-14T06:23:34.368000Z |
| Discovery magnitude (MPC) |
20.30 i |
| Discovery observatory (MPC) |
F51 · Pan-STARRS 1, Haleakala |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2019-03-25.0000000 |
| e |
0.96326067 |
| q (au) |
1.426376 |
| a (au) |
38.824214 |
| i (deg) |
84.341078 |
| Ω (om, deg) |
278.368440 |
| ω (w, deg) |
237.802336 |
| M (ma, deg) |
359.496725 |
等級
散乱 + 全体線形
$$
M_a = (10.529 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
10.529 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.999 |
| 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 |
| 2018-12-18 |
2019-04-22 |
+6.0772 |
-2.366 |
| 2019-08-05 |
2020-06-16 |
+2.0655 |
-3.527 |
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 |
18:47:40.27 |
+03:59:02.9 |
HIP 92254 |
16.42 |
| 2026-02-03 12:00 |
18:47:45.83 |
+03:59:43.4 |
HIP 92254 |
15.34 |
| 2026-02-04 00:00 |
18:47:51.36 |
+04:00:24.3 |
HIP 92254 |
14.36 |
| 2026-02-04 12:00 |
18:47:56.86 |
+04:01:05.5 |
HIP 92254 |
13.47 |
| 2026-02-05 00:00 |
18:48:02.33 |
+04:01:46.9 |
HIP 92254 |
12.70 |
| 2026-02-05 12:00 |
18:48:07.77 |
+04:02:28.7 |
HIP 92254 |
12.07 |
| 2026-02-06 00:00 |
18:48:13.18 |
+04:03:10.8 |
HIP 92254 |
11.60 |
| 2026-02-06 12:00 |
18:48:18.55 |
+04:03:53.1 |
HIP 92254 |
11.31 |
| 2026-02-07 00:00 |
18:48:23.89 |
+04:04:35.7 |
HIP 92254 |
11.21 |
| 2026-02-07 12:00 |
18:48:29.20 |
+04:05:18.6 |
HIP 92254 |
11.31 |
| 2026-02-08 00:00 |
18:48:34.47 |
+04:06:01.8 |
HIP 92254 |
11.59 |
| 2026-02-08 12:00 |
18:48:39.71 |
+04:06:45.3 |
HIP 92254 |
12.04 |
| 2026-02-09 00:00 |
18:48:44.92 |
+04:07:29.1 |
HIP 92254 |
12.65 |
| 2026-02-09 12:00 |
18:48:50.09 |
+04:08:13.1 |
HIP 92254 |
13.38 |
| 2026-02-10 00:00 |
18:48:55.23 |
+04:08:57.4 |
HIP 92254 |
14.22 |
| 2026-02-10 12:00 |
18:49:00.33 |
+04:09:42.0 |
HIP 92254 |
15.15 |
| 2026-02-11 00:00 |
18:49:05.39 |
+04:10:26.9 |
HIP 92254 |
16.15 |
| 2026-02-11 12:00 |
18:49:10.42 |
+04:11:12.0 |
HIP 92254 |
17.21 |
| 2026-02-12 00:00 |
18:49:15.42 |
+04:11:57.4 |
HIP 92254 |
18.31 |
| 2026-02-12 12:00 |
18:49:20.37 |
+04:12:43.1 |
HIP 92254 |
19.45 |
| 2026-02-13 00:00 |
18:49:25.29 |
+04:13:29.0 |
HIP 92254 |
20.62 |
| 2026-02-13 12:00 |
18:49:30.17 |
+04:14:15.2 |
HIP 92254 |
21.82 |
| 2026-02-14 00:00 |
18:49:35.02 |
+04:15:01.7 |
HIP 92254 |
23.03 |
| 2026-02-14 12:00 |
18:49:39.82 |
+04:15:48.4 |
HIP 92254 |
24.26 |
| 2026-02-15 00:00 |
18:49:44.59 |
+04:16:35.3 |
HIP 92254 |
25.50 |
| 2026-02-15 12:00 |
18:49:49.31 |
+04:17:22.6 |
HIP 92254 |
26.74 |
| 2026-02-16 00:00 |
18:49:54.00 |
+04:18:10.0 |
HIP 92254 |
28.00 |
| 2026-02-16 12:00 |
18:49:58.65 |
+04:18:57.7 |
HIP 92254 |
29.26 |
| 2026-02-17 00:00 |
18:50:03.26 |
+04:19:45.7 |
HIP 92562 |
29.89 |
| 2026-02-17 12:00 |
18:50:07.82 |
+04:20:33.9 |
HIP 92562 |
28.50 |
| 2026-02-18 00:00 |
18:50:12.35 |
+04:21:22.3 |
HIP 92562 |
27.11 |
| 2026-02-18 12:00 |
18:50:16.83 |
+04:22:11.0 |
HIP 92562 |
25.73 |
| 2026-02-19 00:00 |
18:50:21.28 |
+04:22:59.9 |
HIP 92562 |
24.35 |
| 2026-02-19 12:00 |
18:50:25.68 |
+04:23:49.0 |
HIP 92562 |
22.99 |
| 2026-02-20 00:00 |
18:50:30.04 |
+04:24:38.4 |
HIP 92562 |
21.63 |
| 2026-02-20 12:00 |
18:50:34.35 |
+04:25:28.0 |
HIP 92562 |
20.28 |
| 2026-02-21 00:00 |
18:50:38.63 |
+04:26:17.8 |
HIP 92562 |
18.93 |
| 2026-02-21 12:00 |
18:50:42.86 |
+04:27:07.8 |
HIP 92562 |
17.59 |
| 2026-02-22 00:00 |
18:50:47.04 |
+04:27:58.0 |
HIP 92562 |
16.26 |
| 2026-02-22 12:00 |
18:50:51.19 |
+04:28:48.5 |
HIP 92562 |
14.95 |
| 2026-02-23 00:00 |
18:50:55.29 |
+04:29:39.2 |
HIP 92562 |
13.64 |
| 2026-02-23 12:00 |
18:50:59.34 |
+04:30:30.0 |
HIP 92562 |
12.34 |
| 2026-02-24 00:00 |
18:51:03.35 |
+04:31:21.1 |
HIP 92562 |
11.05 |