C/2021 R2 (PANSTARRS)

メタデータ

項目
Designation C/2021 R2 (PANSTARRS)
Type C
Perihelion (tp_cal, UTC) 2021-12-25T00:02:41.040960Z
Orbit solution date (soln_date, UTC) 2022-12-08T23:43:01Z
Obs used 126
NEO -
M1 7.000
K1 10.750
PC -
Discovery observation (MPC, UTC) 2021-09-05T08:07:54.134400Z
Discovery magnitude (MPC) 20.48 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
Epoch (epoch_cal, TDB) 2021-11-08.0000000
e 0.99748693
q (au) 7.311968
a (au) 2909.581318
i (deg) 134.470894
Ω (om, deg) 16.283615
ω (w, deg) 32.298315
M (ma, deg) 359.999705

等級

C/2021 R2 (PANSTARRS) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (2.347 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 2.347
n 6.000
gf 1.000
gb -0.500
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)
2026-06-01 00:00 17:26:06.83 +22:04:31.5 HIP 85344 4.33
2026-06-01 12:00 17:25:52.64 +22:04:46.4 HIP 85344 7.32
2026-06-02 00:00 17:25:38.44 +22:05:00.3 HIP 85255 7.60
2026-06-02 12:00 17:25:24.22 +22:05:13.3 HIP 85255 5.78
2026-06-03 00:00 17:25:09.99 +22:05:25.3 HIP 85255 5.56
2026-06-03 12:00 17:24:55.74 +22:05:36.3 HIP 85255 7.10
2026-06-04 00:00 17:24:41.48 +22:05:46.4 HIP 85255 9.59
2026-06-04 12:00 17:24:27.21 +22:05:55.4 HIP 85255 12.48
2026-06-05 00:00 17:24:12.93 +22:06:03.5 HIP 85124 12.23
2026-06-05 12:00 17:23:58.64 +22:06:10.7 HIP 85124 11.24
2026-06-06 00:00 17:23:44.34 +22:06:16.8 HIP 85124 11.18
2026-06-06 12:00 17:23:30.04 +22:06:21.9 HIP 85124 12.04
2026-06-07 00:00 17:23:15.73 +22:06:26.1 HIP 85124 13.67
2026-06-07 12:00 17:23:01.41 +22:06:29.3 HIP 85124 15.82
2026-06-08 00:00 17:22:47.09 +22:06:31.5 HIP 85124 18.31
2026-06-08 12:00 17:22:32.77 +22:06:32.7 HIP 85124 21.03
2026-06-09 00:00 17:22:18.44 +22:06:32.9 HIP 85124 23.89
2026-06-09 12:00 17:22:04.12 +22:06:32.1 HIP 85124 26.85
2026-06-10 00:00 17:21:49.79 +22:06:30.4 HIP 85124 29.88
2026-06-10 12:00 17:21:35.47 +22:06:27.6 HIP 84768 29.47
2026-06-11 00:00 17:21:21.15 +22:06:23.8 HIP 84768 26.34
2026-06-11 12:00 17:21:06.83 +22:06:19.1 HIP 84768 23.26
2026-06-12 00:00 17:20:52.51 +22:06:13.4 HIP 84768 20.25
2026-06-12 12:00 17:20:38.20 +22:06:06.6 HIP 84768 17.35
2026-06-13 00:00 17:20:23.90 +22:05:58.9 HIP 84768 14.61
2026-06-13 12:00 17:20:09.61 +22:05:50.2 HIP 84768 12.15
2026-06-14 00:00 17:19:55.32 +22:05:40.4 HIP 84768 10.18
2026-06-14 12:00 17:19:41.05 +22:05:29.7 HIP 84768 9.01
2026-06-15 00:00 17:19:26.79 +22:05:18.0 HIP 84768 8.97
2026-06-15 12:00 17:19:12.53 +22:05:05.3 HIP 84768 10.07
2026-06-16 00:00 17:18:58.30 +22:04:51.6 HIP 84768 12.00
2026-06-16 12:00 17:18:44.07 +22:04:36.9 HIP 84768 14.42
2026-06-17 00:00 17:18:29.87 +22:04:21.2 HIP 84768 17.13
2026-06-17 12:00 17:18:15.68 +22:04:04.6 HIP 84768 20.01
2026-06-18 00:00 17:18:01.51 +22:03:46.9 HIP 84555 21.25
2026-06-18 12:00 17:17:47.35 +22:03:28.3 HIP 84555 19.68
2026-06-19 00:00 17:17:33.22 +22:03:08.7 HIP 84555 18.58
2026-06-19 12:00 17:17:19.11 +22:02:48.1 HIP 84555 18.05
2026-06-20 00:00 17:17:05.02 +22:02:26.5 HIP 84555 18.11
2026-06-20 12:00 17:16:50.95 +22:02:04.0 HIP 84555 18.78
2026-06-21 00:00 17:16:36.91 +22:01:40.5 HIP 84555 19.98
2026-06-21 12:00 17:16:22.90 +22:01:16.0 HIP 84555 21.63
2026-06-22 00:00 17:16:08.91 +22:00:50.6 HIP 84555 23.62