メタデータ
| 項目 |
値 |
| Designation |
P/2021 Q5 (ATLAS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2021-08-30T10:00:46.546560Z |
| Orbit solution date (soln_date, UTC) |
2025-01-14T17:42:18Z |
| Obs used |
274 |
| NEO |
Yes |
| M1 |
15.800 |
| K1 |
4.500 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2021-08-29T14:33:45.619200Z |
| Discovery magnitude (MPC) |
17.59 o |
| Discovery observatory (MPC) |
T05 · ATLAS-HKO, Haleakala |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2021-09-20.0000000 |
| e |
0.62395172 |
| q (au) |
1.234397 |
| a (au) |
3.282550 |
| i (deg) |
10.733839 |
| Ω (om, deg) |
239.770616 |
| ω (w, deg) |
180.879852 |
| M (ma, deg) |
3.411076 |
等級
散乱 + 全体線形
$$
M_a = (14.774 + 2.320\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
14.774 |
| n |
2.320 |
| gf |
0.999 |
| gb |
-0.998 |
| 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
ファインディングチャート
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
19:23:02.94 |
-14:08:54.6 |
HIP 95266 |
6.76 |
| 2026-05-12 12:00 |
19:22:58.75 |
-14:07:36.3 |
HIP 95266 |
7.94 |
| 2026-05-13 00:00 |
19:22:54.29 |
-14:06:18.4 |
HIP 95266 |
9.25 |
| 2026-05-13 12:00 |
19:22:49.55 |
-14:05:00.9 |
HIP 95266 |
10.68 |
| 2026-05-14 00:00 |
19:22:44.54 |
-14:03:43.9 |
HIP 95266 |
12.20 |
| 2026-05-14 12:00 |
19:22:39.25 |
-14:02:27.3 |
HIP 95179 |
13.21 |
| 2026-05-15 00:00 |
19:22:33.68 |
-14:01:11.2 |
HIP 95179 |
11.88 |
| 2026-05-15 12:00 |
19:22:27.84 |
-13:59:55.5 |
HIP 95179 |
10.63 |
| 2026-05-16 00:00 |
19:22:21.71 |
-13:58:40.3 |
HIP 95179 |
9.54 |
| 2026-05-16 12:00 |
19:22:15.31 |
-13:57:25.6 |
HIP 95179 |
8.69 |
| 2026-05-17 00:00 |
19:22:08.62 |
-13:56:11.3 |
HIP 95179 |
8.19 |
| 2026-05-17 12:00 |
19:22:01.66 |
-13:54:57.5 |
HIP 95179 |
8.14 |
| 2026-05-18 00:00 |
19:21:54.42 |
-13:53:44.3 |
HIP 95179 |
8.58 |
| 2026-05-18 12:00 |
19:21:46.90 |
-13:52:31.5 |
HIP 95179 |
9.49 |
| 2026-05-19 00:00 |
19:21:39.10 |
-13:51:19.2 |
HIP 95179 |
10.77 |
| 2026-05-19 12:00 |
19:21:31.02 |
-13:50:07.4 |
HIP 95179 |
12.34 |
| 2026-05-20 00:00 |
19:21:22.66 |
-13:48:56.2 |
HIP 95179 |
14.13 |
| 2026-05-20 12:00 |
19:21:14.03 |
-13:47:45.5 |
HIP 95179 |
16.09 |
| 2026-05-21 00:00 |
19:21:05.11 |
-13:46:35.2 |
HIP 95179 |
18.18 |
| 2026-05-21 12:00 |
19:20:55.92 |
-13:45:25.6 |
HIP 95179 |
20.39 |
| 2026-05-22 00:00 |
19:20:46.44 |
-13:44:16.4 |
HIP 95179 |
22.69 |
| 2026-05-22 12:00 |
19:20:36.69 |
-13:43:07.8 |
HIP 95179 |
25.09 |
| 2026-05-23 00:00 |
19:20:26.67 |
-13:41:59.7 |
HIP 95061 |
26.92 |
| 2026-05-23 12:00 |
19:20:16.36 |
-13:40:52.2 |
HIP 95061 |
25.99 |
| 2026-05-24 00:00 |
19:20:05.78 |
-13:39:45.3 |
HIP 95061 |
25.36 |
| 2026-05-24 12:00 |
19:19:54.92 |
-13:38:38.9 |
HIP 95061 |
25.06 |
| 2026-05-25 00:00 |
19:19:43.79 |
-13:37:33.0 |
HIP 95061 |
25.13 |
| 2026-05-25 12:00 |
19:19:32.38 |
-13:36:27.7 |
HIP 95061 |
25.57 |
| 2026-05-26 00:00 |
19:19:20.69 |
-13:35:23.0 |
HIP 95061 |
26.40 |
| 2026-05-26 12:00 |
19:19:08.74 |
-13:34:18.9 |
HIP 95061 |
27.59 |
| 2026-05-27 00:00 |
19:18:56.50 |
-13:33:15.4 |
HIP 95061 |
29.13 |
| 2026-05-27 12:00 |
19:18:44.00 |
-13:32:12.4 |
HIP 95061 |
30.97 |
| 2026-05-28 00:00 |
19:18:31.22 |
-13:31:10.0 |
HIP 95061 |
33.09 |
| 2026-05-28 12:00 |
19:18:18.17 |
-13:30:08.3 |
HIP 95061 |
35.45 |
| 2026-05-29 00:00 |
19:18:04.84 |
-13:29:07.1 |
HIP 95061 |
38.02 |
| 2026-05-29 12:00 |
19:17:51.25 |
-13:28:06.5 |
HIP 95061 |
40.78 |
| 2026-05-30 00:00 |
19:17:37.39 |
-13:27:06.5 |
HIP 94731 |
40.23 |
| 2026-05-30 12:00 |
19:17:23.26 |
-13:26:07.2 |
HIP 94731 |
38.09 |
| 2026-05-31 00:00 |
19:17:08.85 |
-13:25:08.4 |
HIP 94731 |
36.16 |
| 2026-05-31 12:00 |
19:16:54.19 |
-13:24:10.3 |
HIP 94731 |
34.51 |
| 2026-06-01 00:00 |
19:16:39.25 |
-13:23:12.8 |
HIP 94731 |
33.20 |
| 2026-06-01 12:00 |
19:16:24.05 |
-13:22:16.0 |
HIP 94731 |
32.30 |
| 2026-06-02 00:00 |
19:16:08.58 |
-13:21:19.8 |
HIP 94731 |
31.85 |