メタデータ
| 項目 |
値 |
| Designation |
C/2019 G2 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2019-12-10T01:37:22.817280Z |
| Orbit solution date (soln_date, UTC) |
2024-04-15T15:43:27Z |
| Obs used |
120 |
| NEO |
- |
| M1 |
16.700 |
| K1 |
5.250 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2019-04-02T10:34:13.152000Z |
| Discovery magnitude (MPC) |
21.30 w |
| 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) |
2019-10-14.0000000 |
| e |
0.99672459 |
| q (au) |
2.291345 |
| a (au) |
699.559136 |
| i (deg) |
159.211459 |
| Ω (om, deg) |
208.142727 |
| ω (w, deg) |
82.653435 |
| M (ma, deg) |
359.996960 |
等級
散乱 + 全体線形
$$
M_a = (14.208 + 4.325\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
14.208 |
| n |
4.325 |
| gf |
1.000 |
| gb |
-0.827 |
| k |
0.995 |
| 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 |
23:40:24.80 |
-17:43:43.9 |
HIP 116846 |
15.34 |
| 2026-09-20 12:00 |
23:40:17.50 |
-17:44:29.2 |
HIP 116724 |
14.09 |
| 2026-09-21 00:00 |
23:40:10.20 |
-17:45:14.2 |
HIP 116724 |
12.24 |
| 2026-09-21 12:00 |
23:40:02.91 |
-17:45:58.9 |
HIP 116724 |
10.40 |
| 2026-09-22 00:00 |
23:39:55.62 |
-17:46:43.3 |
HIP 116724 |
8.60 |
| 2026-09-22 12:00 |
23:39:48.35 |
-17:47:27.4 |
HIP 116724 |
6.83 |
| 2026-09-23 00:00 |
23:39:41.07 |
-17:48:11.2 |
HIP 116724 |
5.15 |
| 2026-09-23 12:00 |
23:39:33.81 |
-17:48:54.7 |
HIP 116724 |
3.66 |
| 2026-09-24 00:00 |
23:39:26.56 |
-17:49:37.9 |
HIP 116724 |
2.71 |
| 2026-09-24 12:00 |
23:39:19.31 |
-17:50:20.8 |
HIP 116724 |
2.87 |
| 2026-09-25 00:00 |
23:39:12.08 |
-17:51:03.4 |
HIP 116724 |
4.01 |
| 2026-09-25 12:00 |
23:39:04.85 |
-17:51:45.6 |
HIP 116724 |
5.55 |
| 2026-09-26 00:00 |
23:38:57.64 |
-17:52:27.5 |
HIP 116724 |
7.23 |
| 2026-09-26 12:00 |
23:38:50.44 |
-17:53:09.1 |
HIP 116724 |
8.97 |
| 2026-09-27 00:00 |
23:38:43.25 |
-17:53:50.4 |
HIP 116724 |
10.75 |
| 2026-09-27 12:00 |
23:38:36.07 |
-17:54:31.3 |
HIP 116724 |
12.54 |
| 2026-09-28 00:00 |
23:38:28.91 |
-17:55:12.0 |
HIP 116724 |
14.33 |
| 2026-09-28 12:00 |
23:38:21.76 |
-17:55:52.2 |
HIP 116724 |
16.13 |
| 2026-09-29 00:00 |
23:38:14.62 |
-17:56:32.2 |
HIP 116724 |
17.93 |
| 2026-09-29 12:00 |
23:38:07.50 |
-17:57:11.8 |
HIP 116724 |
19.73 |
| 2026-09-30 00:00 |
23:38:00.39 |
-17:57:51.1 |
HIP 116724 |
21.52 |
| 2026-09-30 12:00 |
23:37:53.30 |
-17:58:30.0 |
HIP 116724 |
23.32 |
| 2026-10-01 00:00 |
23:37:46.22 |
-17:59:08.5 |
HIP 116724 |
25.10 |
| 2026-10-01 12:00 |
23:37:39.16 |
-17:59:46.8 |
HIP 116724 |
26.89 |
| 2026-10-02 00:00 |
23:37:32.12 |
-18:00:24.6 |
HIP 116532 |
27.65 |
| 2026-10-02 12:00 |
23:37:25.10 |
-18:01:02.2 |
HIP 116532 |
27.87 |
| 2026-10-03 00:00 |
23:37:18.09 |
-18:01:39.3 |
HIP 116532 |
28.20 |
| 2026-10-03 12:00 |
23:37:11.11 |
-18:02:16.1 |
HIP 116532 |
28.64 |
| 2026-10-04 00:00 |
23:37:04.14 |
-18:02:52.6 |
HIP 116532 |
29.16 |
| 2026-10-04 12:00 |
23:36:57.19 |
-18:03:28.7 |
HIP 116532 |
29.78 |
| 2026-10-05 00:00 |
23:36:50.27 |
-18:04:04.4 |
HIP 116532 |
30.48 |
| 2026-10-05 12:00 |
23:36:43.37 |
-18:04:39.7 |
HIP 116532 |
31.26 |
| 2026-10-06 00:00 |
23:36:36.48 |
-18:05:14.7 |
HIP 116532 |
32.10 |
| 2026-10-06 12:00 |
23:36:29.62 |
-18:05:49.3 |
HIP 116532 |
33.01 |
| 2026-10-07 00:00 |
23:36:22.79 |
-18:06:23.5 |
HIP 116397 |
32.62 |
| 2026-10-07 12:00 |
23:36:15.97 |
-18:06:57.3 |
HIP 116397 |
31.32 |
| 2026-10-08 00:00 |
23:36:09.18 |
-18:07:30.8 |
HIP 116397 |
30.07 |
| 2026-10-08 12:00 |
23:36:02.42 |
-18:08:03.9 |
HIP 116397 |
28.88 |
| 2026-10-09 00:00 |
23:35:55.68 |
-18:08:36.6 |
HIP 116397 |
27.74 |
| 2026-10-09 12:00 |
23:35:48.97 |
-18:09:08.9 |
HIP 116397 |
26.67 |
| 2026-10-10 00:00 |
23:35:42.28 |
-18:09:40.8 |
HIP 116397 |
25.68 |
| 2026-10-10 12:00 |
23:35:35.62 |
-18:10:12.3 |
HIP 116397 |
24.76 |
| 2026-10-11 00:00 |
23:35:28.99 |
-18:10:43.4 |
HIP 116397 |
23.94 |