C/2020 T2 (Palomar)

メタデータ

項目
Designation C/2020 T2 (Palomar)
Type C
Perihelion (tp_cal, UTC) 2021-07-11T03:28:26.996160Z
Orbit solution date (soln_date, UTC) 2024-07-30T14:57:24Z
Obs used 2755
NEO -
M1 9.500
K1 10.250
PC 0.030
Discovery observation (MPC, UTC) 2020-10-07T12:21:14.400000Z
Discovery magnitude (MPC) 19.33 r
Discovery observatory (MPC) I41 · Palomar Mountain–ZTF
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 2021-05-15.0000000
e 0.99342864
q (au) 2.054696
a (au) 312.674502
i (deg) 27.872916
Ω (om, deg) 83.048376
ω (w, deg) 150.381486
M (ma, deg) 359.989813

等級

C/2020 T2 (Palomar) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (7.304 + 5.380\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 7.304
n 5.380
gf 1.000
gb -0.950
k 0.999
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
2019-12-11 2021-07-11 +4.3372 -2.066
2021-07-11 2022-09-21 +1.1158 -2.046

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)
2026-03-26 00:00 01:18:07.24 -18:51:51.1 HIP 6052 9.14
2026-03-26 12:00 01:18:15.83 -18:50:48.7 HIP 6052 9.87
2026-03-27 00:00 01:18:24.42 -18:49:46.6 HIP 6052 11.04
2026-03-27 12:00 01:18:33.03 -18:48:44.9 HIP 6052 12.53
2026-03-28 00:00 01:18:41.65 -18:47:43.6 HIP 6052 14.23
2026-03-28 12:00 01:18:50.28 -18:46:42.6 HIP 6052 16.08
2026-03-29 00:00 01:18:58.92 -18:45:42.0 HIP 6052 18.04
2026-03-29 12:00 01:19:07.56 -18:44:41.9 HIP 6052 20.06
2026-03-30 00:00 01:19:16.22 -18:43:42.0 HIP 6052 22.14
2026-03-30 12:00 01:19:24.89 -18:42:42.6 HIP 6052 24.25
2026-03-31 00:00 01:19:33.56 -18:41:43.6 HIP 6052 26.40
2026-03-31 12:00 01:19:42.24 -18:40:44.9 HIP 6052 28.56
2026-04-01 00:00 01:19:50.93 -18:39:46.7 HIP 6052 30.74
2026-04-01 12:00 01:19:59.63 -18:38:48.8 HIP 6052 32.94
2026-04-02 00:00 01:20:08.33 -18:37:51.3 HIP 6425 34.65
2026-04-02 12:00 01:20:17.04 -18:36:54.3 HIP 6425 33.01
2026-04-03 00:00 01:20:25.76 -18:35:57.6 HIP 6425 31.45
2026-04-03 12:00 01:20:34.48 -18:35:01.3 HIP 6425 29.97
2026-04-04 00:00 01:20:43.21 -18:34:05.5 HIP 6425 28.59
2026-04-04 12:00 01:20:51.94 -18:33:10.0 HIP 6425 27.33
2026-04-05 00:00 01:21:00.67 -18:32:15.0 HIP 6425 26.20
2026-04-05 12:00 01:21:09.41 -18:31:20.3 HIP 6425 25.21
2026-04-06 00:00 01:21:18.15 -18:30:26.1 HIP 6425 24.39
2026-04-06 12:00 01:21:26.90 -18:29:32.3 HIP 6425 23.75
2026-04-07 00:00 01:21:35.64 -18:28:38.9 HIP 6425 23.30
2026-04-07 12:00 01:21:44.39 -18:27:46.0 HIP 6425 23.06
2026-04-08 00:00 01:21:53.14 -18:26:53.4 HIP 6425 23.04
2026-04-08 12:00 01:22:01.89 -18:26:01.3 HIP 6425 23.22
2026-04-09 00:00 01:22:10.65 -18:25:09.6 HIP 6425 23.61
2026-04-09 12:00 01:22:19.40 -18:24:18.4 HIP 6425 24.20
2026-04-10 00:00 01:22:28.15 -18:23:27.6 HIP 6425 24.96
2026-04-10 12:00 01:22:36.91 -18:22:37.2 HIP 6425 25.90
2026-04-11 00:00 01:22:45.66 -18:21:47.2 HIP 6425 26.97
2026-04-11 12:00 01:22:54.41 -18:20:57.7 HIP 6585 25.22
2026-04-12 00:00 01:23:03.16 -18:20:08.6 HIP 6585 23.00
2026-04-12 12:00 01:23:11.90 -18:19:20.0 HIP 6585 20.77
2026-04-13 00:00 01:23:20.65 -18:18:31.8 HIP 6585 18.55
2026-04-13 12:00 01:23:29.39 -18:17:44.1 HIP 6585 16.34
2026-04-14 00:00 01:23:38.12 -18:16:56.8 HIP 6585 14.13
2026-04-14 12:00 01:23:46.85 -18:16:10.0 HIP 6585 11.93
2026-04-15 00:00 01:23:55.58 -18:15:23.6 HIP 6585 9.74
2026-04-15 12:00 01:24:04.31 -18:14:37.7 HIP 6585 7.56
2026-04-16 00:00 01:24:13.02 -18:13:52.3 HIP 6585 5.40