メタデータ
| 項目 |
値 |
| Designation |
C/2017 D3 (ATLAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2017-04-26T17:48:37.664640Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:30Z |
| Obs used |
523 |
| NEO |
- |
| M1 |
11.100 |
| K1 |
4.500 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2017-10-06.0000000 |
| e |
1.00243639 |
| q (au) |
4.971286 |
| a (au) |
-2040.429612 |
| i (deg) |
125.570039 |
| Ω (om, deg) |
186.618173 |
| ω (w, deg) |
340.767499 |
| M (ma, deg) |
0.001735 |
等級
散乱 + 全体線形
$$
M_a = (10.067 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
10.067 |
| n |
2.000 |
| gf |
0.997 |
| gb |
-1.000 |
| k |
1.000 |
| δ90 |
9.997 |
| 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 |
04:21:57.66 |
+73:39:47.6 |
HIP 20392 |
4.58 |
| 2026-07-29 12:00 |
04:22:04.75 |
+73:40:41.3 |
HIP 20392 |
5.49 |
| 2026-07-30 00:00 |
04:22:11.72 |
+73:41:35.3 |
HIP 20392 |
6.43 |
| 2026-07-30 12:00 |
04:22:18.56 |
+73:42:29.5 |
HIP 20392 |
7.40 |
| 2026-07-31 00:00 |
04:22:25.28 |
+73:43:23.9 |
HIP 20392 |
8.38 |
| 2026-07-31 12:00 |
04:22:31.87 |
+73:44:18.5 |
HIP 20392 |
9.37 |
| 2026-08-01 00:00 |
04:22:38.33 |
+73:45:13.3 |
HIP 20392 |
10.37 |
| 2026-08-01 12:00 |
04:22:44.66 |
+73:46:08.4 |
HIP 20392 |
11.37 |
| 2026-08-02 00:00 |
04:22:50.86 |
+73:47:03.6 |
HIP 20392 |
12.38 |
| 2026-08-02 12:00 |
04:22:56.93 |
+73:47:59.0 |
HIP 20254 |
12.74 |
| 2026-08-03 00:00 |
04:23:02.87 |
+73:48:54.6 |
HIP 20254 |
12.60 |
| 2026-08-03 12:00 |
04:23:08.67 |
+73:49:50.4 |
HIP 20254 |
12.53 |
| 2026-08-04 00:00 |
04:23:14.35 |
+73:50:46.4 |
HIP 20254 |
12.54 |
| 2026-08-04 12:00 |
04:23:19.88 |
+73:51:42.6 |
HIP 20254 |
12.61 |
| 2026-08-05 00:00 |
04:23:25.29 |
+73:52:38.9 |
HIP 20254 |
12.76 |
| 2026-08-05 12:00 |
04:23:30.55 |
+73:53:35.5 |
HIP 20254 |
12.97 |
| 2026-08-06 00:00 |
04:23:35.68 |
+73:54:32.2 |
HIP 20254 |
13.24 |
| 2026-08-06 12:00 |
04:23:40.67 |
+73:55:29.0 |
HIP 20254 |
13.57 |
| 2026-08-07 00:00 |
04:23:45.51 |
+73:56:26.1 |
HIP 20254 |
13.96 |
| 2026-08-07 12:00 |
04:23:50.22 |
+73:57:23.3 |
HIP 20254 |
14.40 |
| 2026-08-08 00:00 |
04:23:54.78 |
+73:58:20.7 |
HIP 20254 |
14.89 |
| 2026-08-08 12:00 |
04:23:59.21 |
+73:59:18.2 |
HIP 20254 |
15.41 |
| 2026-08-09 00:00 |
04:24:03.48 |
+74:00:15.9 |
HIP 20254 |
15.98 |
| 2026-08-09 12:00 |
04:24:07.61 |
+74:01:13.7 |
HIP 20254 |
16.57 |
| 2026-08-10 00:00 |
04:24:11.60 |
+74:02:11.7 |
HIP 20254 |
17.20 |
| 2026-08-10 12:00 |
04:24:15.43 |
+74:03:09.8 |
HIP 20254 |
17.85 |
| 2026-08-11 00:00 |
04:24:19.12 |
+74:04:08.1 |
HIP 20254 |
18.52 |
| 2026-08-11 12:00 |
04:24:22.66 |
+74:05:06.5 |
HIP 20254 |
19.22 |
| 2026-08-12 00:00 |
04:24:26.05 |
+74:06:05.0 |
HIP 20254 |
19.93 |
| 2026-08-12 12:00 |
04:24:29.28 |
+74:07:03.6 |
HIP 20254 |
20.66 |
| 2026-08-13 00:00 |
04:24:32.36 |
+74:08:02.4 |
HIP 20254 |
21.41 |
| 2026-08-13 12:00 |
04:24:35.29 |
+74:09:01.3 |
HIP 20254 |
22.16 |
| 2026-08-14 00:00 |
04:24:38.06 |
+74:10:00.3 |
HIP 20254 |
22.93 |
| 2026-08-14 12:00 |
04:24:40.68 |
+74:10:59.4 |
HIP 20254 |
23.71 |
| 2026-08-15 00:00 |
04:24:43.14 |
+74:11:58.6 |
HIP 20254 |
24.50 |
| 2026-08-15 12:00 |
04:24:45.45 |
+74:12:57.9 |
HIP 20254 |
25.30 |
| 2026-08-16 00:00 |
04:24:47.59 |
+74:13:57.3 |
HIP 20254 |
26.10 |
| 2026-08-16 12:00 |
04:24:49.57 |
+74:14:56.8 |
HIP 20254 |
26.91 |
| 2026-08-17 00:00 |
04:24:51.40 |
+74:15:56.4 |
HIP 20254 |
27.73 |
| 2026-08-17 12:00 |
04:24:53.06 |
+74:16:56.0 |
HIP 20254 |
28.55 |
| 2026-08-18 00:00 |
04:24:54.56 |
+74:17:55.8 |
HIP 20249 |
28.49 |
| 2026-08-18 12:00 |
04:24:55.90 |
+74:18:55.6 |
HIP 20249 |
27.79 |
| 2026-08-19 00:00 |
04:24:57.08 |
+74:19:55.4 |
HIP 20249 |
27.10 |