メタデータ
| 項目 |
値 |
| Designation |
425P/Kowalski |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2021-09-21T00:11:04.882560Z |
| Orbit solution date (soln_date, UTC) |
2024-02-01T00:43:56Z |
| Obs used |
427 |
| NEO |
- |
| M1 |
7.100 |
| K1 |
20.500 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2021-07-20T14:22:26.860800Z |
| Discovery magnitude (MPC) |
20.36 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) |
2017-07-26.0000000 |
| e |
0.54240402 |
| q (au) |
2.901345 |
| a (au) |
6.340409 |
| i (deg) |
16.427088 |
| Ω (om, deg) |
210.335779 |
| ω (w, deg) |
200.221889 |
| M (ma, deg) |
266.286495 |
等級
散乱 + 全体線形
$$
M_a = (11.353 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
11.353 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.633 |
| k |
0.800 |
| 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 |
| 2020-08-19 |
2021-09-16 |
+11.9451 |
-5.152 |
| 2021-09-30 |
2023-01-25 |
-3.5885 |
+1.530 |
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) |
| 2026-09-20 00:00 |
13:22:20.69 |
-09:57:13.0 |
HIP 65163 |
17.06 |
| 2026-09-20 12:00 |
13:22:34.18 |
-09:58:17.9 |
HIP 65163 |
20.23 |
| 2026-09-21 00:00 |
13:22:47.71 |
-09:59:23.0 |
HIP 65163 |
23.49 |
| 2026-09-21 12:00 |
13:23:01.26 |
-10:00:28.3 |
HIP 65412 |
21.33 |
| 2026-09-22 00:00 |
13:23:14.84 |
-10:01:33.7 |
HIP 65412 |
17.82 |
| 2026-09-22 12:00 |
13:23:28.45 |
-10:02:39.3 |
HIP 65412 |
14.30 |
| 2026-09-23 00:00 |
13:23:42.09 |
-10:03:45.1 |
HIP 65412 |
10.79 |
| 2026-09-23 12:00 |
13:23:55.75 |
-10:04:51.1 |
HIP 65412 |
7.29 |
| 2026-09-24 00:00 |
13:24:09.45 |
-10:05:57.2 |
HIP 65412 |
3.86 |
| 2026-09-24 12:00 |
13:24:23.17 |
-10:07:03.4 |
HIP 65412 |
1.33 |
| 2026-09-25 00:00 |
13:24:36.91 |
-10:08:09.9 |
HIP 65412 |
3.73 |
| 2026-09-25 12:00 |
13:24:50.69 |
-10:09:16.4 |
HIP 65412 |
7.18 |
| 2026-09-26 00:00 |
13:25:04.48 |
-10:10:23.1 |
HIP 65412 |
10.71 |
| 2026-09-26 12:00 |
13:25:18.30 |
-10:11:30.0 |
HIP 65412 |
14.27 |
| 2026-09-27 00:00 |
13:25:32.15 |
-10:12:37.0 |
HIP 65412 |
17.84 |
| 2026-09-27 12:00 |
13:25:46.02 |
-10:13:44.1 |
HIP 65412 |
21.42 |
| 2026-09-28 00:00 |
13:25:59.91 |
-10:14:51.4 |
HIP 65412 |
25.02 |
| 2026-09-28 12:00 |
13:26:13.83 |
-10:15:58.8 |
HIP 65412 |
28.61 |
| 2026-09-29 00:00 |
13:26:27.77 |
-10:17:06.3 |
HIP 65412 |
32.22 |
| 2026-09-29 12:00 |
13:26:41.73 |
-10:18:14.0 |
HIP 65412 |
35.83 |
| 2026-09-30 00:00 |
13:26:55.71 |
-10:19:21.7 |
HIP 65801 |
35.09 |
| 2026-09-30 12:00 |
13:27:09.72 |
-10:20:29.6 |
HIP 65801 |
31.57 |
| 2026-10-01 00:00 |
13:27:23.74 |
-10:21:37.6 |
HIP 65801 |
28.06 |
| 2026-10-01 12:00 |
13:27:37.79 |
-10:22:45.7 |
HIP 65801 |
24.59 |
| 2026-10-02 00:00 |
13:27:51.85 |
-10:23:54.0 |
HIP 65801 |
21.17 |
| 2026-10-02 12:00 |
13:28:05.93 |
-10:25:02.3 |
HIP 65801 |
17.83 |
| 2026-10-03 00:00 |
13:28:20.03 |
-10:26:10.7 |
HIP 65801 |
14.63 |
| 2026-10-03 12:00 |
13:28:34.15 |
-10:27:19.2 |
HIP 65801 |
11.70 |
| 2026-10-04 00:00 |
13:28:48.29 |
-10:28:27.9 |
HIP 65801 |
9.29 |
| 2026-10-04 12:00 |
13:29:02.45 |
-10:29:36.6 |
HIP 65801 |
7.91 |
| 2026-10-05 00:00 |
13:29:16.62 |
-10:30:45.4 |
HIP 65801 |
8.11 |
| 2026-10-05 12:00 |
13:29:30.81 |
-10:31:54.2 |
HIP 65801 |
9.79 |
| 2026-10-06 00:00 |
13:29:45.01 |
-10:33:03.2 |
HIP 65821 |
9.92 |
| 2026-10-06 12:00 |
13:29:59.23 |
-10:34:12.2 |
HIP 65821 |
10.26 |
| 2026-10-07 00:00 |
13:30:13.46 |
-10:35:21.3 |
HIP 65821 |
11.80 |
| 2026-10-07 12:00 |
13:30:27.70 |
-10:36:30.5 |
HIP 65821 |
14.16 |
| 2026-10-08 00:00 |
13:30:41.96 |
-10:37:39.8 |
HIP 65821 |
17.00 |
| 2026-10-08 12:00 |
13:30:56.24 |
-10:38:49.1 |
HIP 65821 |
20.11 |
| 2026-10-09 00:00 |
13:31:10.52 |
-10:39:58.4 |
HIP 65821 |
23.40 |
| 2026-10-09 12:00 |
13:31:24.82 |
-10:41:07.8 |
HIP 65991 |
26.27 |
| 2026-10-10 00:00 |
13:31:39.12 |
-10:42:17.3 |
HIP 65991 |
26.87 |
| 2026-10-10 12:00 |
13:31:53.44 |
-10:43:26.8 |
HIP 65991 |
27.95 |
| 2026-10-11 00:00 |
13:32:07.77 |
-10:44:36.3 |
HIP 65991 |
29.46 |