メタデータ
| 項目 |
値 |
| Designation |
C/2020 T4 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2021-07-05T05:56:29.909760Z |
| Orbit solution date (soln_date, UTC) |
2021-07-01T22:12:53Z |
| Obs used |
171 |
| NEO |
- |
| M1 |
15.800 |
| K1 |
4.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2020-10-15T14:08:31.113600Z |
| Discovery magnitude (MPC) |
21.00 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) |
2020-11-23.0000000 |
| e |
1.00004087 |
| q (au) |
2.191878 |
| a (au) |
-53626.423966 |
| i (deg) |
83.817389 |
| Ω (om, deg) |
50.622331 |
| ω (w, deg) |
79.602529 |
| M (ma, deg) |
-0.000018 |
等級
散乱 + 全体線形
$$
M_a = (14.969 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
14.969 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.849 |
| 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
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
14:15:32.72 |
-50:33:28.9 |
HIP 69668 |
19.59 |
| 2026-07-29 12:00 |
14:15:32.41 |
-50:32:33.5 |
HIP 69668 |
20.51 |
| 2026-07-30 00:00 |
14:15:32.20 |
-50:31:38.5 |
HIP 69780 |
20.08 |
| 2026-07-30 12:00 |
14:15:32.10 |
-50:30:43.9 |
HIP 69780 |
19.43 |
| 2026-07-31 00:00 |
14:15:32.09 |
-50:29:49.6 |
HIP 69780 |
18.80 |
| 2026-07-31 12:00 |
14:15:32.18 |
-50:28:55.6 |
HIP 69780 |
18.18 |
| 2026-08-01 00:00 |
14:15:32.38 |
-50:28:02.0 |
HIP 69780 |
17.58 |
| 2026-08-01 12:00 |
14:15:32.67 |
-50:27:08.8 |
HIP 69780 |
17.00 |
| 2026-08-02 00:00 |
14:15:33.07 |
-50:26:15.9 |
HIP 69780 |
16.43 |
| 2026-08-02 12:00 |
14:15:33.56 |
-50:25:23.4 |
HIP 69780 |
15.88 |
| 2026-08-03 00:00 |
14:15:34.15 |
-50:24:31.2 |
HIP 69780 |
15.35 |
| 2026-08-03 12:00 |
14:15:34.84 |
-50:23:39.5 |
HIP 69780 |
14.85 |
| 2026-08-04 00:00 |
14:15:35.63 |
-50:22:48.1 |
HIP 69780 |
14.36 |
| 2026-08-04 12:00 |
14:15:36.52 |
-50:21:57.1 |
HIP 69780 |
13.90 |
| 2026-08-05 00:00 |
14:15:37.50 |
-50:21:06.5 |
HIP 69780 |
13.47 |
| 2026-08-05 12:00 |
14:15:38.58 |
-50:20:16.4 |
HIP 69780 |
13.07 |
| 2026-08-06 00:00 |
14:15:39.76 |
-50:19:26.6 |
HIP 69780 |
12.69 |
| 2026-08-06 12:00 |
14:15:41.04 |
-50:18:37.2 |
HIP 69780 |
12.35 |
| 2026-08-07 00:00 |
14:15:42.41 |
-50:17:48.2 |
HIP 69780 |
12.05 |
| 2026-08-07 12:00 |
14:15:43.88 |
-50:16:59.6 |
HIP 69780 |
11.78 |
| 2026-08-08 00:00 |
14:15:45.44 |
-50:16:11.4 |
HIP 69780 |
11.55 |
| 2026-08-08 12:00 |
14:15:47.10 |
-50:15:23.7 |
HIP 69780 |
11.36 |
| 2026-08-09 00:00 |
14:15:48.86 |
-50:14:36.4 |
HIP 69780 |
11.22 |
| 2026-08-09 12:00 |
14:15:50.71 |
-50:13:49.5 |
HIP 69780 |
11.12 |
| 2026-08-10 00:00 |
14:15:52.66 |
-50:13:03.0 |
HIP 69780 |
11.07 |
| 2026-08-10 12:00 |
14:15:54.70 |
-50:12:17.0 |
HIP 69780 |
11.06 |
| 2026-08-11 00:00 |
14:15:56.83 |
-50:11:31.4 |
HIP 69780 |
11.10 |
| 2026-08-11 12:00 |
14:15:59.06 |
-50:10:46.3 |
HIP 69780 |
11.18 |
| 2026-08-12 00:00 |
14:16:01.38 |
-50:10:01.6 |
HIP 69780 |
11.31 |
| 2026-08-12 12:00 |
14:16:03.79 |
-50:09:17.3 |
HIP 69780 |
11.48 |
| 2026-08-13 00:00 |
14:16:06.30 |
-50:08:33.5 |
HIP 69780 |
11.69 |
| 2026-08-13 12:00 |
14:16:08.90 |
-50:07:50.2 |
HIP 69780 |
11.94 |
| 2026-08-14 00:00 |
14:16:11.59 |
-50:07:07.3 |
HIP 69780 |
12.22 |
| 2026-08-14 12:00 |
14:16:14.37 |
-50:06:24.9 |
HIP 69781 |
11.97 |
| 2026-08-15 00:00 |
14:16:17.24 |
-50:05:43.0 |
HIP 69781 |
11.13 |
| 2026-08-15 12:00 |
14:16:20.20 |
-50:05:01.5 |
HIP 69781 |
10.30 |
| 2026-08-16 00:00 |
14:16:23.25 |
-50:04:20.5 |
HIP 69781 |
9.46 |
| 2026-08-16 12:00 |
14:16:26.39 |
-50:03:40.0 |
HIP 69781 |
8.61 |
| 2026-08-17 00:00 |
14:16:29.62 |
-50:03:00.0 |
HIP 69781 |
7.77 |
| 2026-08-17 12:00 |
14:16:32.94 |
-50:02:20.4 |
HIP 69781 |
6.92 |
| 2026-08-18 00:00 |
14:16:36.34 |
-50:01:41.3 |
HIP 69781 |
6.08 |
| 2026-08-18 12:00 |
14:16:39.83 |
-50:01:02.7 |
HIP 69781 |
5.23 |
| 2026-08-19 00:00 |
14:16:43.41 |
-50:00:24.6 |
HIP 69781 |
4.38 |