メタデータ
| 項目 |
値 |
| Designation |
C/2021 O3 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2022-04-21T00:59:54.507840Z |
| Orbit solution date (soln_date, UTC) |
2024-08-08T14:32:18Z |
| Obs used |
760 |
| NEO |
- |
| M1 |
13.600 |
| K1 |
4.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2021-07-26T11:32:37.104000Z |
| Discovery magnitude (MPC) |
19.87 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) |
2021-10-30.0000000 |
| e |
1.00015130 |
| q (au) |
0.287322 |
| a (au) |
-1899.062785 |
| i (deg) |
56.772789 |
| Ω (om, deg) |
189.027335 |
| ω (w, deg) |
299.983286 |
| M (ma, deg) |
-0.002061 |
等級
散乱 + 全体線形
$$
M_a = (15.384 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
15.384 |
| n |
2.000 |
| gf |
0.800 |
| gb |
-0.680 |
| k |
0.800 |
| 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 |
| 2021-07-26 |
2021-09-18 |
+2.7400 |
-1.427 |
| 2021-09-18 |
2021-11-07 |
+8.8781 |
-4.666 |
| 2021-11-07 |
2021-12-08 |
+4.2020 |
-2.285 |
| 2021-12-08 |
2022-04-19 |
+4.8581 |
-2.406 |
| 2022-04-22 |
2022-07-12 |
-0.0579 |
+1.173 |
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) |
| 2026-07-29 00:00 |
19:24:29.17 |
+36:40:08.5 |
HIP 95370 |
13.83 |
| 2026-07-29 12:00 |
19:24:19.93 |
+36:39:25.8 |
HIP 95370 |
12.63 |
| 2026-07-30 00:00 |
19:24:10.73 |
+36:38:42.2 |
HIP 95370 |
11.63 |
| 2026-07-30 12:00 |
19:24:01.56 |
+36:37:57.8 |
HIP 95370 |
10.89 |
| 2026-07-31 00:00 |
19:23:52.43 |
+36:37:12.5 |
HIP 95370 |
10.46 |
| 2026-07-31 12:00 |
19:23:43.32 |
+36:36:26.4 |
HIP 95370 |
10.38 |
| 2026-08-01 00:00 |
19:23:34.26 |
+36:35:39.4 |
HIP 95370 |
10.67 |
| 2026-08-01 12:00 |
19:23:25.23 |
+36:34:51.5 |
HIP 95370 |
11.28 |
| 2026-08-02 00:00 |
19:23:16.23 |
+36:34:02.9 |
HIP 95370 |
12.18 |
| 2026-08-02 12:00 |
19:23:07.28 |
+36:33:13.4 |
HIP 95370 |
13.30 |
| 2026-08-03 00:00 |
19:22:58.36 |
+36:32:23.0 |
HIP 95370 |
14.59 |
| 2026-08-03 12:00 |
19:22:49.48 |
+36:31:31.9 |
HIP 95370 |
16.01 |
| 2026-08-04 00:00 |
19:22:40.64 |
+36:30:39.9 |
HIP 95370 |
17.53 |
| 2026-08-04 12:00 |
19:22:31.84 |
+36:29:47.1 |
HIP 95370 |
19.13 |
| 2026-08-05 00:00 |
19:22:23.08 |
+36:28:53.5 |
HIP 95370 |
20.78 |
| 2026-08-05 12:00 |
19:22:14.37 |
+36:27:59.1 |
HIP 95370 |
22.47 |
| 2026-08-06 00:00 |
19:22:05.70 |
+36:27:03.8 |
HIP 95030 |
24.06 |
| 2026-08-06 12:00 |
19:21:57.07 |
+36:26:07.8 |
HIP 95030 |
22.21 |
| 2026-08-07 00:00 |
19:21:48.49 |
+36:25:11.0 |
HIP 95030 |
20.39 |
| 2026-08-07 12:00 |
19:21:39.95 |
+36:24:13.4 |
HIP 95030 |
18.60 |
| 2026-08-08 00:00 |
19:21:31.45 |
+36:23:15.0 |
HIP 95030 |
16.87 |
| 2026-08-08 12:00 |
19:21:23.01 |
+36:22:15.8 |
HIP 95030 |
15.20 |
| 2026-08-09 00:00 |
19:21:14.61 |
+36:21:15.8 |
HIP 95030 |
13.62 |
| 2026-08-09 12:00 |
19:21:06.26 |
+36:20:15.1 |
HIP 95030 |
12.16 |
| 2026-08-10 00:00 |
19:20:57.96 |
+36:19:13.6 |
HIP 95030 |
10.88 |
| 2026-08-10 12:00 |
19:20:49.71 |
+36:18:11.3 |
HIP 95030 |
9.84 |
| 2026-08-11 00:00 |
19:20:41.50 |
+36:17:08.3 |
HIP 95030 |
9.12 |
| 2026-08-11 12:00 |
19:20:33.36 |
+36:16:04.6 |
HIP 95030 |
8.80 |
| 2026-08-12 00:00 |
19:20:25.26 |
+36:15:00.1 |
HIP 95030 |
8.92 |
| 2026-08-12 12:00 |
19:20:17.21 |
+36:13:54.9 |
HIP 95030 |
9.47 |
| 2026-08-13 00:00 |
19:20:09.22 |
+36:12:48.9 |
HIP 95030 |
10.38 |
| 2026-08-13 12:00 |
19:20:01.29 |
+36:11:42.2 |
HIP 95030 |
11.56 |
| 2026-08-14 00:00 |
19:19:53.41 |
+36:10:34.8 |
HIP 95030 |
12.93 |
| 2026-08-14 12:00 |
19:19:45.58 |
+36:09:26.7 |
HIP 94912 |
13.42 |
| 2026-08-15 00:00 |
19:19:37.81 |
+36:08:17.9 |
HIP 94912 |
11.48 |
| 2026-08-15 12:00 |
19:19:30.10 |
+36:07:08.5 |
HIP 94912 |
9.55 |
| 2026-08-16 00:00 |
19:19:22.44 |
+36:05:58.3 |
HIP 94912 |
7.62 |
| 2026-08-16 12:00 |
19:19:14.85 |
+36:04:47.4 |
HIP 94912 |
5.71 |
| 2026-08-17 00:00 |
19:19:07.31 |
+36:03:35.9 |
HIP 94912 |
3.82 |
| 2026-08-17 12:00 |
19:18:59.83 |
+36:02:23.7 |
HIP 94912 |
2.04 |
| 2026-08-18 00:00 |
19:18:52.42 |
+36:01:10.8 |
HIP 94912 |
1.10 |
| 2026-08-18 12:00 |
19:18:45.06 |
+35:59:57.3 |
HIP 94912 |
2.39 |
| 2026-08-19 00:00 |
19:18:37.77 |
+35:58:43.2 |
HIP 94912 |
4.21 |