メタデータ
| 項目 |
値 |
| Designation |
C/2021 J2 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2021-09-22T11:24:15.621120Z |
| Orbit solution date (soln_date, UTC) |
2023-12-06T01:14:09Z |
| Obs used |
218 |
| NEO |
- |
| M1 |
13.600 |
| K1 |
4.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2021-05-10T09:49:17.990400Z |
| Discovery magnitude (MPC) |
22.06 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) |
2022-02-01.0000000 |
| e |
0.95985091 |
| q (au) |
4.706567 |
| a (au) |
117.227257 |
| i (deg) |
156.209020 |
| Ω (om, deg) |
23.329370 |
| ω (w, deg) |
172.059356 |
| M (ma, deg) |
0.102134 |
等級
散乱 + 全体線形
$$
M_a = (14.688 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
14.688 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.612 |
| 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
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
06:41:17.12 |
-00:53:54.1 |
HIP 31874 |
36.72 |
| 2026-03-26 12:00 |
06:41:14.04 |
-00:52:47.1 |
HIP 32058 |
36.93 |
| 2026-03-27 00:00 |
06:41:11.04 |
-00:51:40.2 |
HIP 32058 |
36.07 |
| 2026-03-27 12:00 |
06:41:08.13 |
-00:50:33.6 |
HIP 32058 |
35.23 |
| 2026-03-28 00:00 |
06:41:05.32 |
-00:49:27.1 |
HIP 32058 |
34.42 |
| 2026-03-28 12:00 |
06:41:02.59 |
-00:48:20.8 |
HIP 32058 |
33.64 |
| 2026-03-29 00:00 |
06:40:59.95 |
-00:47:14.6 |
HIP 32058 |
32.89 |
| 2026-03-29 12:00 |
06:40:57.40 |
-00:46:08.7 |
HIP 32058 |
32.16 |
| 2026-03-30 00:00 |
06:40:54.94 |
-00:45:02.9 |
HIP 32058 |
31.46 |
| 2026-03-30 12:00 |
06:40:52.57 |
-00:43:57.4 |
HIP 32058 |
30.78 |
| 2026-03-31 00:00 |
06:40:50.29 |
-00:42:52.0 |
HIP 32058 |
30.13 |
| 2026-03-31 12:00 |
06:40:48.09 |
-00:41:46.9 |
HIP 32058 |
29.51 |
| 2026-04-01 00:00 |
06:40:45.98 |
-00:40:41.9 |
HIP 32058 |
28.92 |
| 2026-04-01 12:00 |
06:40:43.96 |
-00:39:37.2 |
HIP 32058 |
28.36 |
| 2026-04-02 00:00 |
06:40:42.03 |
-00:38:32.7 |
HIP 32058 |
27.82 |
| 2026-04-02 12:00 |
06:40:40.18 |
-00:37:28.4 |
HIP 32058 |
27.32 |
| 2026-04-03 00:00 |
06:40:38.42 |
-00:36:24.3 |
HIP 32058 |
26.84 |
| 2026-04-03 12:00 |
06:40:36.75 |
-00:35:20.4 |
HIP 32058 |
26.39 |
| 2026-04-04 00:00 |
06:40:35.16 |
-00:34:16.8 |
HIP 32058 |
25.97 |
| 2026-04-04 12:00 |
06:40:33.66 |
-00:33:13.4 |
HIP 32058 |
25.58 |
| 2026-04-05 00:00 |
06:40:32.24 |
-00:32:10.2 |
HIP 32058 |
25.22 |
| 2026-04-05 12:00 |
06:40:30.91 |
-00:31:07.3 |
HIP 32058 |
24.88 |
| 2026-04-06 00:00 |
06:40:29.66 |
-00:30:04.6 |
HIP 32058 |
24.58 |
| 2026-04-06 12:00 |
06:40:28.50 |
-00:29:02.1 |
HIP 32058 |
24.30 |
| 2026-04-07 00:00 |
06:40:27.42 |
-00:28:00.0 |
HIP 32058 |
24.06 |
| 2026-04-07 12:00 |
06:40:26.43 |
-00:26:57.9 |
HIP 32058 |
23.84 |
| 2026-04-08 00:00 |
06:40:25.51 |
-00:25:56.2 |
HIP 32058 |
23.65 |
| 2026-04-08 12:00 |
06:40:24.69 |
-00:24:54.8 |
HIP 32058 |
23.48 |
| 2026-04-09 00:00 |
06:40:23.94 |
-00:23:53.6 |
HIP 32058 |
23.35 |
| 2026-04-09 12:00 |
06:40:23.28 |
-00:22:52.7 |
HIP 32058 |
23.24 |
| 2026-04-10 00:00 |
06:40:22.70 |
-00:21:52.0 |
HIP 32058 |
23.15 |
| 2026-04-10 12:00 |
06:40:22.20 |
-00:20:51.6 |
HIP 32058 |
23.09 |
| 2026-04-11 00:00 |
06:40:21.79 |
-00:19:51.5 |
HIP 32058 |
23.06 |
| 2026-04-11 12:00 |
06:40:21.45 |
-00:18:51.7 |
HIP 32058 |
23.05 |
| 2026-04-12 00:00 |
06:40:21.20 |
-00:17:52.1 |
HIP 32058 |
23.06 |
| 2026-04-12 12:00 |
06:40:21.03 |
-00:16:52.8 |
HIP 32058 |
23.10 |
| 2026-04-13 00:00 |
06:40:20.93 |
-00:15:53.9 |
HIP 32058 |
23.15 |
| 2026-04-13 12:00 |
06:40:20.92 |
-00:14:55.2 |
HIP 32058 |
23.23 |
| 2026-04-14 00:00 |
06:40:20.99 |
-00:13:56.7 |
HIP 32058 |
23.33 |
| 2026-04-14 12:00 |
06:40:21.14 |
-00:12:58.6 |
HIP 32058 |
23.45 |
| 2026-04-15 00:00 |
06:40:21.36 |
-00:12:00.8 |
HIP 32058 |
23.59 |
| 2026-04-15 12:00 |
06:40:21.67 |
-00:11:03.3 |
HIP 32058 |
23.74 |
| 2026-04-16 00:00 |
06:40:22.05 |
-00:10:06.1 |
HIP 32058 |
23.91 |