メタデータ
| 項目 |
値 |
| Designation |
C/2021 C5 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2023-02-11T00:59:44.805120Z |
| Orbit solution date (soln_date, UTC) |
2024-07-08T10:14:37Z |
| Obs used |
456 |
| NEO |
- |
| M1 |
12.100 |
| K1 |
5.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2021-02-12T08:17:13.660800Z |
| Discovery magnitude (MPC) |
21.01 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) |
2022-03-02.0000000 |
| e |
0.99926635 |
| q (au) |
3.241820 |
| a (au) |
4418.763332 |
| i (deg) |
50.784623 |
| Ω (om, deg) |
323.689906 |
| ω (w, deg) |
270.917360 |
| M (ma, deg) |
359.998839 |
等級
散乱 + 全体線形
$$
M_a = (12.668 + 3.655\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
12.668 |
| n |
3.655 |
| gf |
1.000 |
| gb |
-0.758 |
| 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 |
| 2020-12-22 |
2022-01-05 |
+4.2672 |
-3.352 |
| 2022-01-05 |
2022-06-07 |
+5.6932 |
-3.927 |
| 2022-06-07 |
2023-02-07 |
-20.1432 |
+11.501 |
| 2023-02-16 |
2024-07-03 |
+12.5302 |
-5.302 |
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) |
| 2026-06-01 00:00 |
22:35:20.81 |
+09:32:26.1 |
HIP 111399 |
19.39 |
| 2026-06-01 12:00 |
22:35:20.91 |
+09:33:55.7 |
HIP 111399 |
19.98 |
| 2026-06-02 00:00 |
22:35:20.91 |
+09:35:24.8 |
HIP 111399 |
20.64 |
| 2026-06-02 12:00 |
22:35:20.82 |
+09:36:53.5 |
HIP 111399 |
21.36 |
| 2026-06-03 00:00 |
22:35:20.65 |
+09:38:21.7 |
HIP 111399 |
22.13 |
| 2026-06-03 12:00 |
22:35:20.38 |
+09:39:49.4 |
HIP 111399 |
22.94 |
| 2026-06-04 00:00 |
22:35:20.02 |
+09:41:16.7 |
HIP 111399 |
23.80 |
| 2026-06-04 12:00 |
22:35:19.57 |
+09:42:43.5 |
HIP 111399 |
24.69 |
| 2026-06-05 00:00 |
22:35:19.02 |
+09:44:09.8 |
HIP 111399 |
25.61 |
| 2026-06-05 12:00 |
22:35:18.39 |
+09:45:35.7 |
HIP 111399 |
26.56 |
| 2026-06-06 00:00 |
22:35:17.67 |
+09:47:01.1 |
HIP 111399 |
27.53 |
| 2026-06-06 12:00 |
22:35:16.85 |
+09:48:25.9 |
HIP 111399 |
28.52 |
| 2026-06-07 00:00 |
22:35:15.94 |
+09:49:50.3 |
HIP 111399 |
29.52 |
| 2026-06-07 12:00 |
22:35:14.94 |
+09:51:14.2 |
HIP 111518 |
29.00 |
| 2026-06-08 00:00 |
22:35:13.85 |
+09:52:37.6 |
HIP 111518 |
27.70 |
| 2026-06-08 12:00 |
22:35:12.67 |
+09:54:00.5 |
HIP 111518 |
26.43 |
| 2026-06-09 00:00 |
22:35:11.40 |
+09:55:22.9 |
HIP 111518 |
25.18 |
| 2026-06-09 12:00 |
22:35:10.03 |
+09:56:44.8 |
HIP 111518 |
23.96 |
| 2026-06-10 00:00 |
22:35:08.57 |
+09:58:06.1 |
HIP 111518 |
22.79 |
| 2026-06-10 12:00 |
22:35:07.02 |
+09:59:26.9 |
HIP 111518 |
21.65 |
| 2026-06-11 00:00 |
22:35:05.38 |
+10:00:47.2 |
HIP 111518 |
20.57 |
| 2026-06-11 12:00 |
22:35:03.65 |
+10:02:07.0 |
HIP 111518 |
19.54 |
| 2026-06-12 00:00 |
22:35:01.82 |
+10:03:26.3 |
HIP 111518 |
18.58 |
| 2026-06-12 12:00 |
22:34:59.91 |
+10:04:45.0 |
HIP 111518 |
17.70 |
| 2026-06-13 00:00 |
22:34:57.90 |
+10:06:03.1 |
HIP 111518 |
16.91 |
| 2026-06-13 12:00 |
22:34:55.80 |
+10:07:20.7 |
HIP 111518 |
16.22 |
| 2026-06-14 00:00 |
22:34:53.60 |
+10:08:37.8 |
HIP 111518 |
15.65 |
| 2026-06-14 12:00 |
22:34:51.32 |
+10:09:54.3 |
HIP 111518 |
15.21 |
| 2026-06-15 00:00 |
22:34:48.94 |
+10:11:10.2 |
HIP 111518 |
14.91 |
| 2026-06-15 12:00 |
22:34:46.48 |
+10:12:25.6 |
HIP 111518 |
14.76 |
| 2026-06-16 00:00 |
22:34:43.92 |
+10:13:40.4 |
HIP 111518 |
14.76 |
| 2026-06-16 12:00 |
22:34:41.26 |
+10:14:54.6 |
HIP 111518 |
14.92 |
| 2026-06-17 00:00 |
22:34:38.52 |
+10:16:08.3 |
HIP 111518 |
15.24 |
| 2026-06-17 12:00 |
22:34:35.69 |
+10:17:21.4 |
HIP 111518 |
15.69 |
| 2026-06-18 00:00 |
22:34:32.77 |
+10:18:33.9 |
HIP 111518 |
16.28 |
| 2026-06-18 12:00 |
22:34:29.75 |
+10:19:45.8 |
HIP 111518 |
16.98 |
| 2026-06-19 00:00 |
22:34:26.65 |
+10:20:57.1 |
HIP 111518 |
17.79 |
| 2026-06-19 12:00 |
22:34:23.45 |
+10:22:07.8 |
HIP 111518 |
18.70 |
| 2026-06-20 00:00 |
22:34:20.17 |
+10:23:18.0 |
HIP 111518 |
19.68 |
| 2026-06-20 12:00 |
22:34:16.79 |
+10:24:27.5 |
HIP 111518 |
20.74 |
| 2026-06-21 00:00 |
22:34:13.33 |
+10:25:36.4 |
HIP 111300 |
20.84 |
| 2026-06-21 12:00 |
22:34:09.77 |
+10:26:44.7 |
HIP 111300 |
20.07 |
| 2026-06-22 00:00 |
22:34:06.13 |
+10:27:52.4 |
HIP 111300 |
19.36 |