メタデータ
| 項目 |
値 |
| Designation |
C/2017 M4 (ATLAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2019-01-18T08:09:45.547200Z |
| Orbit solution date (soln_date, UTC) |
2022-07-31T01:42:28Z |
| Obs used |
3296 |
| NEO |
- |
| M1 |
9.400 |
| K1 |
6.000 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2018-06-17.0000000 |
| e |
1.00108487 |
| q (au) |
3.251701 |
| a (au) |
-2997.319774 |
| i (deg) |
105.657087 |
| Ω (om, deg) |
65.868353 |
| ω (w, deg) |
167.652626 |
| M (ma, deg) |
-0.001293 |
等級
散乱 + 全体線形
$$
M_a = (7.294 + 2.998\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
7.294 |
| n |
2.998 |
| gf |
0.999 |
| gb |
-1.000 |
| k |
1.000 |
| 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) |
| 2026-05-12 00:00 |
05:58:00.21 |
-32:52:16.5 |
HIP 28236 |
2.12 |
| 2026-05-12 12:00 |
05:58:05.52 |
-32:51:17.2 |
HIP 28236 |
1.92 |
| 2026-05-13 00:00 |
05:58:10.86 |
-32:50:18.4 |
HIP 28236 |
2.72 |
| 2026-05-13 12:00 |
05:58:16.24 |
-32:49:20.2 |
HIP 28236 |
3.94 |
| 2026-05-14 00:00 |
05:58:21.65 |
-32:48:22.5 |
HIP 28282 |
2.90 |
| 2026-05-14 12:00 |
05:58:27.10 |
-32:47:25.4 |
HIP 28282 |
1.45 |
| 2026-05-15 00:00 |
05:58:32.57 |
-32:46:28.8 |
HIP 28282 |
0.44 |
| 2026-05-15 12:00 |
05:58:38.08 |
-32:45:32.7 |
HIP 28282 |
1.64 |
| 2026-05-16 00:00 |
05:58:43.62 |
-32:44:37.3 |
HIP 28282 |
3.10 |
| 2026-05-16 12:00 |
05:58:49.19 |
-32:43:42.3 |
HIP 28282 |
4.58 |
| 2026-05-17 00:00 |
05:58:54.79 |
-32:42:48.0 |
HIP 28282 |
6.06 |
| 2026-05-17 12:00 |
05:59:00.42 |
-32:41:54.1 |
HIP 28282 |
7.54 |
| 2026-05-18 00:00 |
05:59:06.09 |
-32:41:00.9 |
HIP 28282 |
9.02 |
| 2026-05-18 12:00 |
05:59:11.77 |
-32:40:08.2 |
HIP 28282 |
10.50 |
| 2026-05-19 00:00 |
05:59:17.49 |
-32:39:16.1 |
HIP 28282 |
11.98 |
| 2026-05-19 12:00 |
05:59:23.24 |
-32:38:24.5 |
HIP 28282 |
13.46 |
| 2026-05-20 00:00 |
05:59:29.01 |
-32:37:33.5 |
HIP 28282 |
14.94 |
| 2026-05-20 12:00 |
05:59:34.82 |
-32:36:43.1 |
HIP 28282 |
16.42 |
| 2026-05-21 00:00 |
05:59:40.64 |
-32:35:53.3 |
HIP 28282 |
17.90 |
| 2026-05-21 12:00 |
05:59:46.50 |
-32:35:04.0 |
HIP 28282 |
19.38 |
| 2026-05-22 00:00 |
05:59:52.38 |
-32:34:15.3 |
HIP 28282 |
20.85 |
| 2026-05-22 12:00 |
05:59:58.28 |
-32:33:27.2 |
HIP 28282 |
22.33 |
| 2026-05-23 00:00 |
06:00:04.21 |
-32:32:39.7 |
HIP 28335 |
22.48 |
| 2026-05-23 12:00 |
06:00:10.17 |
-32:31:52.7 |
HIP 28335 |
22.40 |
| 2026-05-24 00:00 |
06:00:16.15 |
-32:31:06.3 |
HIP 28335 |
22.42 |
| 2026-05-24 12:00 |
06:00:22.15 |
-32:30:20.6 |
HIP 28335 |
22.56 |
| 2026-05-25 00:00 |
06:00:28.18 |
-32:29:35.3 |
HIP 28335 |
22.80 |
| 2026-05-25 12:00 |
06:00:34.22 |
-32:28:50.7 |
HIP 28335 |
23.14 |
| 2026-05-26 00:00 |
06:00:40.29 |
-32:28:06.7 |
HIP 28335 |
23.58 |
| 2026-05-26 12:00 |
06:00:46.38 |
-32:27:23.2 |
HIP 28335 |
24.11 |
| 2026-05-27 00:00 |
06:00:52.50 |
-32:26:40.3 |
HIP 28335 |
24.73 |
| 2026-05-27 12:00 |
06:00:58.63 |
-32:25:58.1 |
HIP 28335 |
25.43 |
| 2026-05-28 00:00 |
06:01:04.79 |
-32:25:16.4 |
HIP 28335 |
26.20 |
| 2026-05-28 12:00 |
06:01:10.96 |
-32:24:35.3 |
HIP 28335 |
27.04 |
| 2026-05-29 00:00 |
06:01:17.16 |
-32:23:54.7 |
HIP 28335 |
27.94 |
| 2026-05-29 12:00 |
06:01:23.37 |
-32:23:14.8 |
HIP 28335 |
28.89 |
| 2026-05-30 00:00 |
06:01:29.60 |
-32:22:35.5 |
HIP 28679 |
29.07 |
| 2026-05-30 12:00 |
06:01:35.85 |
-32:21:56.7 |
HIP 28679 |
27.63 |
| 2026-05-31 00:00 |
06:01:42.12 |
-32:21:18.6 |
HIP 28679 |
26.20 |
| 2026-05-31 12:00 |
06:01:48.41 |
-32:20:41.1 |
HIP 28679 |
24.78 |
| 2026-06-01 00:00 |
06:01:54.71 |
-32:20:04.1 |
HIP 28679 |
23.37 |
| 2026-06-01 12:00 |
06:02:01.03 |
-32:19:27.7 |
HIP 28679 |
21.96 |
| 2026-06-02 00:00 |
06:02:07.37 |
-32:18:52.0 |
HIP 28679 |
20.57 |