メタデータ
| 項目 |
値 |
| Designation |
C/2021 R7 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2021-04-14T11:28:22.085760Z |
| Orbit solution date (soln_date, UTC) |
2022-12-08T23:43:02Z |
| Obs used |
63 |
| NEO |
- |
| M1 |
7.700 |
| K1 |
14.000 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2021-09-05T10:13:05.577600Z |
| Discovery magnitude (MPC) |
22.01 w |
| Discovery observatory (MPC) |
F52 · Pan-STARRS 2, Haleakala |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2021-11-23.0000000 |
| e |
0.99519043 |
| q (au) |
5.640615 |
| a (au) |
1172.790949 |
| i (deg) |
158.854146 |
| Ω (om, deg) |
170.145186 |
| ω (w, deg) |
139.994299 |
| M (ma, deg) |
0.005461 |
等級
散乱 + 全体線形
$$
M_a = (7.384 + 5.410\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
7.384 |
| n |
5.410 |
| gf |
0.999 |
| gb |
-0.856 |
| 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
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
20:19:18.42 |
-37:22:06.0 |
HIP 100335 |
28.09 |
| 2026-03-26 12:00 |
20:19:20.79 |
-37:22:44.8 |
HIP 100335 |
27.29 |
| 2026-03-27 00:00 |
20:19:23.07 |
-37:23:23.9 |
HIP 100335 |
26.50 |
| 2026-03-27 12:00 |
20:19:25.27 |
-37:24:03.5 |
HIP 100335 |
25.72 |
| 2026-03-28 00:00 |
20:19:27.39 |
-37:24:43.5 |
HIP 100335 |
24.95 |
| 2026-03-28 12:00 |
20:19:29.43 |
-37:25:23.9 |
HIP 100335 |
24.18 |
| 2026-03-29 00:00 |
20:19:31.39 |
-37:26:04.7 |
HIP 100335 |
23.42 |
| 2026-03-29 12:00 |
20:19:33.26 |
-37:26:45.9 |
HIP 100335 |
22.67 |
| 2026-03-30 00:00 |
20:19:35.05 |
-37:27:27.5 |
HIP 100335 |
21.93 |
| 2026-03-30 12:00 |
20:19:36.75 |
-37:28:09.5 |
HIP 100335 |
21.20 |
| 2026-03-31 00:00 |
20:19:38.37 |
-37:28:51.9 |
HIP 100335 |
20.48 |
| 2026-03-31 12:00 |
20:19:39.90 |
-37:29:34.7 |
HIP 100335 |
19.77 |
| 2026-04-01 00:00 |
20:19:41.35 |
-37:30:18.0 |
HIP 100335 |
19.07 |
| 2026-04-01 12:00 |
20:19:42.71 |
-37:31:01.6 |
HIP 100335 |
18.40 |
| 2026-04-02 00:00 |
20:19:43.99 |
-37:31:45.5 |
HIP 100335 |
17.73 |
| 2026-04-02 12:00 |
20:19:45.18 |
-37:32:29.9 |
HIP 100335 |
17.09 |
| 2026-04-03 00:00 |
20:19:46.28 |
-37:33:14.7 |
HIP 100335 |
16.47 |
| 2026-04-03 12:00 |
20:19:47.30 |
-37:33:59.9 |
HIP 100335 |
15.87 |
| 2026-04-04 00:00 |
20:19:48.23 |
-37:34:45.4 |
HIP 100335 |
15.30 |
| 2026-04-04 12:00 |
20:19:49.07 |
-37:35:31.4 |
HIP 100335 |
14.77 |
| 2026-04-05 00:00 |
20:19:49.82 |
-37:36:17.7 |
HIP 100335 |
14.26 |
| 2026-04-05 12:00 |
20:19:50.48 |
-37:37:04.5 |
HIP 100335 |
13.80 |
| 2026-04-06 00:00 |
20:19:51.06 |
-37:37:51.6 |
HIP 100335 |
13.39 |
| 2026-04-06 12:00 |
20:19:51.54 |
-37:38:39.0 |
HIP 100335 |
13.02 |
| 2026-04-07 00:00 |
20:19:51.93 |
-37:39:26.9 |
HIP 100335 |
12.71 |
| 2026-04-07 12:00 |
20:19:52.24 |
-37:40:15.2 |
HIP 100335 |
12.45 |
| 2026-04-08 00:00 |
20:19:52.45 |
-37:41:03.8 |
HIP 100335 |
12.27 |
| 2026-04-08 12:00 |
20:19:52.57 |
-37:41:52.8 |
HIP 100335 |
12.15 |
| 2026-04-09 00:00 |
20:19:52.60 |
-37:42:42.2 |
HIP 100335 |
12.10 |
| 2026-04-09 12:00 |
20:19:52.54 |
-37:43:31.9 |
HIP 100335 |
12.13 |
| 2026-04-10 00:00 |
20:19:52.39 |
-37:44:22.1 |
HIP 100335 |
12.23 |
| 2026-04-10 12:00 |
20:19:52.14 |
-37:45:12.5 |
HIP 100335 |
12.41 |
| 2026-04-11 00:00 |
20:19:51.80 |
-37:46:03.4 |
HIP 100335 |
12.66 |
| 2026-04-11 12:00 |
20:19:51.37 |
-37:46:54.6 |
HIP 100335 |
12.98 |
| 2026-04-12 00:00 |
20:19:50.84 |
-37:47:46.2 |
HIP 100335 |
13.37 |
| 2026-04-12 12:00 |
20:19:50.22 |
-37:48:38.2 |
HIP 100335 |
13.82 |
| 2026-04-13 00:00 |
20:19:49.51 |
-37:49:30.5 |
HIP 100335 |
14.33 |
| 2026-04-13 12:00 |
20:19:48.69 |
-37:50:23.2 |
HIP 100335 |
14.90 |
| 2026-04-14 00:00 |
20:19:47.79 |
-37:51:16.2 |
HIP 100335 |
15.51 |
| 2026-04-14 12:00 |
20:19:46.79 |
-37:52:09.6 |
HIP 100335 |
16.17 |
| 2026-04-15 00:00 |
20:19:45.69 |
-37:53:03.3 |
HIP 100335 |
16.87 |
| 2026-04-15 12:00 |
20:19:44.50 |
-37:53:57.4 |
HIP 100335 |
17.61 |
| 2026-04-16 00:00 |
20:19:43.21 |
-37:54:51.8 |
HIP 100119 |
16.87 |