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) |
| 2026-09-20 00:00 |
19:13:18.44 |
+34:23:01.1 |
HIP 94479 |
5.48 |
| 2026-09-20 12:00 |
19:13:15.99 |
+34:21:21.4 |
HIP 94479 |
6.54 |
| 2026-09-21 00:00 |
19:13:13.63 |
+34:19:41.5 |
HIP 94479 |
7.83 |
| 2026-09-21 12:00 |
19:13:11.35 |
+34:18:01.6 |
HIP 94479 |
9.26 |
| 2026-09-22 00:00 |
19:13:09.15 |
+34:16:21.5 |
HIP 94479 |
10.77 |
| 2026-09-22 12:00 |
19:13:07.03 |
+34:14:41.4 |
HIP 94479 |
12.32 |
| 2026-09-23 00:00 |
19:13:04.99 |
+34:13:01.1 |
HIP 94479 |
13.91 |
| 2026-09-23 12:00 |
19:13:03.04 |
+34:11:20.8 |
HIP 94517 |
14.39 |
| 2026-09-24 00:00 |
19:13:01.17 |
+34:09:40.4 |
HIP 94517 |
15.02 |
| 2026-09-24 12:00 |
19:12:59.39 |
+34:08:00.0 |
HIP 94517 |
15.80 |
| 2026-09-25 00:00 |
19:12:57.68 |
+34:06:19.4 |
HIP 94517 |
16.70 |
| 2026-09-25 12:00 |
19:12:56.06 |
+34:04:38.8 |
HIP 94517 |
17.70 |
| 2026-09-26 00:00 |
19:12:54.52 |
+34:02:58.1 |
HIP 94517 |
18.80 |
| 2026-09-26 12:00 |
19:12:53.06 |
+34:01:17.5 |
HIP 94517 |
19.97 |
| 2026-09-27 00:00 |
19:12:51.69 |
+33:59:36.7 |
HIP 94517 |
21.20 |
| 2026-09-27 12:00 |
19:12:50.39 |
+33:57:56.0 |
HIP 94517 |
22.47 |
| 2026-09-28 00:00 |
19:12:49.18 |
+33:56:15.2 |
HIP 94517 |
23.79 |
| 2026-09-28 12:00 |
19:12:48.05 |
+33:54:34.5 |
HIP 94517 |
25.14 |
| 2026-09-29 00:00 |
19:12:47.01 |
+33:52:53.7 |
HIP 94517 |
26.52 |
| 2026-09-29 12:00 |
19:12:46.04 |
+33:51:12.9 |
HIP 94517 |
27.93 |
| 2026-09-30 00:00 |
19:12:45.16 |
+33:49:32.2 |
HIP 94226 |
29.09 |
| 2026-09-30 12:00 |
19:12:44.36 |
+33:47:51.4 |
HIP 94226 |
30.01 |
| 2026-10-01 00:00 |
19:12:43.64 |
+33:46:10.7 |
HIP 94226 |
31.00 |
| 2026-10-01 12:00 |
19:12:43.01 |
+33:44:30.0 |
HIP 94226 |
32.07 |
| 2026-10-02 00:00 |
19:12:42.45 |
+33:42:49.4 |
HIP 94229 |
32.19 |
| 2026-10-02 12:00 |
19:12:41.98 |
+33:41:08.8 |
HIP 94229 |
30.94 |
| 2026-10-03 00:00 |
19:12:41.59 |
+33:39:28.2 |
HIP 94229 |
29.73 |
| 2026-10-03 12:00 |
19:12:41.29 |
+33:37:47.7 |
HIP 94229 |
28.59 |
| 2026-10-04 00:00 |
19:12:41.06 |
+33:36:07.3 |
HIP 94229 |
27.52 |
| 2026-10-04 12:00 |
19:12:40.92 |
+33:34:27.0 |
HIP 94229 |
26.53 |
| 2026-10-05 00:00 |
19:12:40.85 |
+33:32:46.7 |
HIP 94229 |
25.62 |
| 2026-10-05 12:00 |
19:12:40.87 |
+33:31:06.6 |
HIP 94229 |
24.81 |
| 2026-10-06 00:00 |
19:12:40.98 |
+33:29:26.5 |
HIP 94229 |
24.10 |
| 2026-10-06 12:00 |
19:12:41.16 |
+33:27:46.6 |
HIP 94229 |
23.50 |
| 2026-10-07 00:00 |
19:12:41.42 |
+33:26:06.7 |
HIP 94229 |
23.03 |
| 2026-10-07 12:00 |
19:12:41.77 |
+33:24:27.0 |
HIP 94229 |
22.69 |
| 2026-10-08 00:00 |
19:12:42.20 |
+33:22:47.5 |
HIP 94229 |
22.48 |
| 2026-10-08 12:00 |
19:12:42.71 |
+33:21:08.0 |
HIP 94229 |
22.42 |
| 2026-10-09 00:00 |
19:12:43.30 |
+33:19:28.7 |
HIP 94229 |
22.49 |
| 2026-10-09 12:00 |
19:12:43.97 |
+33:17:49.6 |
HIP 94229 |
22.70 |
| 2026-10-10 00:00 |
19:12:44.72 |
+33:16:10.6 |
HIP 94229 |
23.04 |
| 2026-10-10 12:00 |
19:12:45.55 |
+33:14:31.8 |
HIP 94503 |
22.39 |
| 2026-10-11 00:00 |
19:12:46.46 |
+33:12:53.2 |
HIP 94503 |
21.15 |