メタデータ
| 項目 |
値 |
| Designation |
427P/ATLAS |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2017-07-28T00:34:10.565760Z |
| Orbit solution date (soln_date, UTC) |
2026-06-09T11:12:48Z |
| Obs used |
442 |
| NEO |
- |
| M1 |
10.700 |
| K1 |
19.250 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2021-06-09T01:43:41.059200Z |
| Discovery magnitude (MPC) |
24.00 G |
| Discovery observatory (MPC) |
I11 · Gemini South Observatory, Cerro Pachon |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2017-11-22.0000000 |
| e |
0.31304463 |
| q (au) |
2.178224 |
| a (au) |
3.170837 |
| i (deg) |
11.849363 |
| Ω (om, deg) |
252.391031 |
| ω (w, deg) |
99.944253 |
| M (ma, deg) |
20.419303 |
等級
散乱 + 全体線形
$$
M_a = (20.000 + 3.940\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
20.000 |
| n |
3.940 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.840 |
| 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 |
11:45:53.73 |
-08:30:05.0 |
HIP 57566 |
32.01 |
| 2026-07-29 12:00 |
11:46:18.80 |
-08:31:41.1 |
HIP 57566 |
25.61 |
| 2026-07-30 00:00 |
11:46:43.96 |
-08:33:18.3 |
HIP 57566 |
19.19 |
| 2026-07-30 12:00 |
11:47:09.22 |
-08:34:56.4 |
HIP 57566 |
12.74 |
| 2026-07-31 00:00 |
11:47:34.56 |
-08:36:35.5 |
HIP 57566 |
6.28 |
| 2026-07-31 12:00 |
11:48:00.01 |
-08:38:15.5 |
HIP 57570 |
0.61 |
| 2026-08-01 00:00 |
11:48:25.54 |
-08:39:56.5 |
HIP 57570 |
6.65 |
| 2026-08-01 12:00 |
11:48:51.16 |
-08:41:38.5 |
HIP 57570 |
13.19 |
| 2026-08-02 00:00 |
11:49:16.87 |
-08:43:21.3 |
HIP 57585 |
17.32 |
| 2026-08-02 12:00 |
11:49:42.68 |
-08:45:05.2 |
HIP 57585 |
22.35 |
| 2026-08-03 00:00 |
11:50:08.57 |
-08:46:49.9 |
HIP 57631 |
25.92 |
| 2026-08-03 12:00 |
11:50:34.55 |
-08:48:35.6 |
HIP 57790 |
28.63 |
| 2026-08-04 00:00 |
11:51:00.62 |
-08:50:22.2 |
HIP 57790 |
26.03 |
| 2026-08-04 12:00 |
11:51:26.78 |
-08:52:09.7 |
HIP 57790 |
24.99 |
| 2026-08-05 00:00 |
11:51:53.03 |
-08:53:58.1 |
HIP 57790 |
25.71 |
| 2026-08-05 12:00 |
11:52:19.36 |
-08:55:47.4 |
HIP 57790 |
28.08 |
| 2026-08-06 00:00 |
11:52:45.78 |
-08:57:37.7 |
HIP 57790 |
31.74 |
| 2026-08-06 12:00 |
11:53:12.28 |
-08:59:28.8 |
HIP 58094 |
35.09 |
| 2026-08-07 00:00 |
11:53:38.87 |
-09:01:20.8 |
HIP 58094 |
29.35 |
| 2026-08-07 12:00 |
11:54:05.54 |
-09:03:13.7 |
HIP 58094 |
24.16 |
| 2026-08-08 00:00 |
11:54:32.29 |
-09:05:07.5 |
HIP 58094 |
19.97 |
| 2026-08-08 12:00 |
11:54:59.13 |
-09:07:02.2 |
HIP 58094 |
17.54 |
| 2026-08-09 00:00 |
11:55:26.05 |
-09:08:57.7 |
HIP 58094 |
17.65 |
| 2026-08-09 12:00 |
11:55:53.06 |
-09:10:54.1 |
HIP 58094 |
20.28 |
| 2026-08-10 00:00 |
11:56:20.14 |
-09:12:51.3 |
HIP 58094 |
24.66 |
| 2026-08-10 12:00 |
11:56:47.31 |
-09:14:49.4 |
HIP 58094 |
30.04 |
| 2026-08-11 00:00 |
11:57:14.55 |
-09:16:48.4 |
HIP 58437 |
24.92 |
| 2026-08-11 12:00 |
11:57:41.88 |
-09:18:48.2 |
HIP 58437 |
18.10 |
| 2026-08-12 00:00 |
11:58:09.28 |
-09:20:48.8 |
HIP 58437 |
11.50 |
| 2026-08-12 12:00 |
11:58:36.76 |
-09:22:50.2 |
HIP 58437 |
6.06 |
| 2026-08-13 00:00 |
11:59:04.32 |
-09:24:52.5 |
HIP 58437 |
6.43 |
| 2026-08-13 12:00 |
11:59:31.95 |
-09:26:55.6 |
HIP 58437 |
12.14 |
| 2026-08-14 00:00 |
11:59:59.66 |
-09:28:59.5 |
HIP 58437 |
18.85 |
| 2026-08-14 12:00 |
12:00:27.45 |
-09:31:04.2 |
HIP 58437 |
25.82 |
| 2026-08-15 00:00 |
12:00:55.31 |
-09:33:09.7 |
HIP 58437 |
32.89 |
| 2026-08-15 12:00 |
12:01:23.24 |
-09:35:15.9 |
HIP 58437 |
40.02 |
| 2026-08-16 00:00 |
12:01:51.25 |
-09:37:23.0 |
HIP 58865 |
39.65 |
| 2026-08-16 12:00 |
12:02:19.33 |
-09:39:30.8 |
HIP 58865 |
34.49 |
| 2026-08-17 00:00 |
12:02:47.47 |
-09:41:39.4 |
HIP 58865 |
30.18 |
| 2026-08-17 12:00 |
12:03:15.69 |
-09:43:48.7 |
HIP 58865 |
27.17 |
| 2026-08-18 00:00 |
12:03:43.98 |
-09:45:58.8 |
HIP 58865 |
25.93 |
| 2026-08-18 12:00 |
12:04:12.34 |
-09:48:09.7 |
HIP 58925 |
19.73 |
| 2026-08-19 00:00 |
12:04:40.77 |
-09:50:21.3 |
HIP 58925 |
14.50 |