C/2020 T2 (Palomar)
メタデータ
| 項目 |
値 |
| 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 |
値 |
| 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
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 |
値 |
| 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) |
| 2026-02-03 00:00 |
01:05:58.73 |
-21:00:33.9 |
HIP 5056 |
17.79 |
| 2026-02-03 12:00 |
01:06:03.69 |
-20:59:11.5 |
HIP 5056 |
18.90 |
| 2026-02-04 00:00 |
01:06:08.70 |
-20:57:49.1 |
HIP 5056 |
20.12 |
| 2026-02-04 12:00 |
01:06:13.77 |
-20:56:26.7 |
HIP 5056 |
21.44 |
| 2026-02-05 00:00 |
01:06:18.89 |
-20:55:04.3 |
HIP 5056 |
22.84 |
| 2026-02-05 12:00 |
01:06:24.07 |
-20:53:42.0 |
HIP 5068 |
24.16 |
| 2026-02-06 00:00 |
01:06:29.31 |
-20:52:19.6 |
HIP 5068 |
24.79 |
| 2026-02-06 12:00 |
01:06:34.61 |
-20:50:57.2 |
HIP 5068 |
25.55 |
| 2026-02-07 00:00 |
01:06:39.95 |
-20:49:34.9 |
HIP 5068 |
26.43 |
| 2026-02-07 12:00 |
01:06:45.36 |
-20:48:12.6 |
HIP 5068 |
27.42 |
| 2026-02-08 00:00 |
01:06:50.82 |
-20:46:50.3 |
HIP 5068 |
28.52 |
| 2026-02-08 12:00 |
01:06:56.33 |
-20:45:28.1 |
HIP 5068 |
29.70 |
| 2026-02-09 00:00 |
01:07:01.89 |
-20:44:05.9 |
HIP 5068 |
30.96 |
| 2026-02-09 12:00 |
01:07:07.51 |
-20:42:43.7 |
HIP 5068 |
32.30 |
| 2026-02-10 00:00 |
01:07:13.18 |
-20:41:21.6 |
HIP 5068 |
33.71 |
| 2026-02-10 12:00 |
01:07:18.91 |
-20:39:59.5 |
HIP 5068 |
35.17 |
| 2026-02-11 00:00 |
01:07:24.68 |
-20:38:37.5 |
HIP 5068 |
36.69 |
| 2026-02-11 12:00 |
01:07:30.51 |
-20:37:15.5 |
HIP 5180 |
37.99 |
| 2026-02-12 00:00 |
01:07:36.39 |
-20:35:53.6 |
HIP 5180 |
37.47 |
| 2026-02-12 12:00 |
01:07:42.32 |
-20:34:31.8 |
HIP 5452 |
36.06 |
| 2026-02-13 00:00 |
01:07:48.30 |
-20:33:10.0 |
HIP 5452 |
34.12 |
| 2026-02-13 12:00 |
01:07:54.34 |
-20:31:48.3 |
HIP 5452 |
32.18 |
| 2026-02-14 00:00 |
01:08:00.42 |
-20:30:26.7 |
HIP 5452 |
30.23 |
| 2026-02-14 12:00 |
01:08:06.55 |
-20:29:05.2 |
HIP 5452 |
28.28 |
| 2026-02-15 00:00 |
01:08:12.73 |
-20:27:43.8 |
HIP 5452 |
26.32 |
| 2026-02-15 12:00 |
01:08:18.95 |
-20:26:22.4 |
HIP 5452 |
24.35 |
| 2026-02-16 00:00 |
01:08:25.23 |
-20:25:01.2 |
HIP 5452 |
22.38 |
| 2026-02-16 12:00 |
01:08:31.55 |
-20:23:40.1 |
HIP 5452 |
20.41 |
| 2026-02-17 00:00 |
01:08:37.92 |
-20:22:19.0 |
HIP 5452 |
18.44 |
| 2026-02-17 12:00 |
01:08:44.34 |
-20:20:58.1 |
HIP 5452 |
16.46 |
| 2026-02-18 00:00 |
01:08:50.80 |
-20:19:37.3 |
HIP 5452 |
14.49 |
| 2026-02-18 12:00 |
01:08:57.31 |
-20:18:16.7 |
HIP 5452 |
12.53 |
| 2026-02-19 00:00 |
01:09:03.86 |
-20:16:56.1 |
HIP 5452 |
10.59 |
| 2026-02-19 12:00 |
01:09:10.46 |
-20:15:35.7 |
HIP 5452 |
8.68 |
| 2026-02-20 00:00 |
01:09:17.10 |
-20:14:15.4 |
HIP 5452 |
6.84 |
| 2026-02-20 12:00 |
01:09:23.79 |
-20:12:55.3 |
HIP 5452 |
5.16 |
| 2026-02-21 00:00 |
01:09:30.52 |
-20:11:35.3 |
HIP 5452 |
3.84 |
| 2026-02-21 12:00 |
01:09:37.29 |
-20:10:15.4 |
HIP 5452 |
3.38 |
| 2026-02-22 00:00 |
01:09:44.10 |
-20:08:55.7 |
HIP 5452 |
4.09 |
| 2026-02-22 12:00 |
01:09:50.96 |
-20:07:36.2 |
HIP 5452 |
5.53 |
| 2026-02-23 00:00 |
01:09:57.86 |
-20:06:16.8 |
HIP 5452 |
7.29 |
| 2026-02-23 12:00 |
01:10:04.80 |
-20:04:57.6 |
HIP 5452 |
9.20 |
| 2026-02-24 00:00 |
01:10:11.78 |
-20:03:38.5 |
HIP 5452 |
11.17 |