メタデータ
| 項目 |
値 |
| Designation |
C/2014 A4 (SONEAR) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2015-09-05T20:45:05.630400Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:46Z |
| Obs used |
2742 |
| NEO |
- |
| M1 |
9.500 |
| K1 |
5.750 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2015-10-28.0000000 |
| e |
1.00085476 |
| q (au) |
4.180180 |
| a (au) |
-4890.464363 |
| i (deg) |
121.359968 |
| Ω (om, deg) |
29.727220 |
| ω (w, deg) |
356.788414 |
| M (ma, deg) |
0.000150 |
等級
散乱 + 全体線形
$$
M_a = (10.149 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
10.149 |
| n |
2.000 |
| gf |
0.830 |
| gb |
-0.500 |
| k |
0.927 |
| δ90 |
1.000 |
| 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 |
| 2014-01-12 |
2014-10-21 |
+6.8415 |
-5.586 |
| 2014-10-21 |
2015-09-01 |
-9.4186 |
+6.023 |
| 2015-09-06 |
2016-12-24 |
-2.1233 |
+1.498 |
| 2016-12-24 |
2017-09-17 |
+16.6300 |
-12.756 |
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) |
| 2026-05-12 00:00 |
16:43:32.61 |
+22:45:24.0 |
HIP 81925 |
23.29 |
| 2026-05-12 12:00 |
16:43:26.95 |
+22:45:44.9 |
HIP 81925 |
24.02 |
| 2026-05-13 00:00 |
16:43:21.29 |
+22:46:05.4 |
HIP 81925 |
24.79 |
| 2026-05-13 12:00 |
16:43:15.60 |
+22:46:25.5 |
HIP 81875 |
25.49 |
| 2026-05-14 00:00 |
16:43:09.90 |
+22:46:45.1 |
HIP 81875 |
25.33 |
| 2026-05-14 12:00 |
16:43:04.19 |
+22:47:04.4 |
HIP 81875 |
25.26 |
| 2026-05-15 00:00 |
16:42:58.45 |
+22:47:23.1 |
HIP 81875 |
25.26 |
| 2026-05-15 12:00 |
16:42:52.71 |
+22:47:41.5 |
HIP 81875 |
25.34 |
| 2026-05-16 00:00 |
16:42:46.95 |
+22:47:59.4 |
HIP 81665 |
25.47 |
| 2026-05-16 12:00 |
16:42:41.17 |
+22:48:16.9 |
HIP 81665 |
24.17 |
| 2026-05-17 00:00 |
16:42:35.39 |
+22:48:33.9 |
HIP 81665 |
22.87 |
| 2026-05-17 12:00 |
16:42:29.59 |
+22:48:50.5 |
HIP 81665 |
21.57 |
| 2026-05-18 00:00 |
16:42:23.77 |
+22:49:06.7 |
HIP 81665 |
20.28 |
| 2026-05-18 12:00 |
16:42:17.95 |
+22:49:22.4 |
HIP 81665 |
19.00 |
| 2026-05-19 00:00 |
16:42:12.11 |
+22:49:37.7 |
HIP 81665 |
17.72 |
| 2026-05-19 12:00 |
16:42:06.26 |
+22:49:52.5 |
HIP 81665 |
16.46 |
| 2026-05-20 00:00 |
16:42:00.40 |
+22:50:06.9 |
HIP 81665 |
15.21 |
| 2026-05-20 12:00 |
16:41:54.54 |
+22:50:20.8 |
HIP 81665 |
13.98 |
| 2026-05-21 00:00 |
16:41:48.66 |
+22:50:34.3 |
HIP 81665 |
12.77 |
| 2026-05-21 12:00 |
16:41:42.77 |
+22:50:47.3 |
HIP 81665 |
11.60 |
| 2026-05-22 00:00 |
16:41:36.88 |
+22:51:00.0 |
HIP 81665 |
10.47 |
| 2026-05-22 12:00 |
16:41:30.97 |
+22:51:12.0 |
HIP 81665 |
9.40 |
| 2026-05-23 00:00 |
16:41:25.06 |
+22:51:23.7 |
HIP 81665 |
8.41 |
| 2026-05-23 12:00 |
16:41:19.14 |
+22:51:34.9 |
HIP 81665 |
7.54 |
| 2026-05-24 00:00 |
16:41:13.22 |
+22:51:45.7 |
HIP 81665 |
6.83 |
| 2026-05-24 12:00 |
16:41:07.28 |
+22:51:56.0 |
HIP 81665 |
6.33 |
| 2026-05-25 00:00 |
16:41:01.34 |
+22:52:05.8 |
HIP 81665 |
6.10 |
| 2026-05-25 12:00 |
16:40:55.40 |
+22:52:15.2 |
HIP 81665 |
6.18 |
| 2026-05-26 00:00 |
16:40:49.45 |
+22:52:24.2 |
HIP 81665 |
6.54 |
| 2026-05-26 12:00 |
16:40:43.50 |
+22:52:32.6 |
HIP 81665 |
7.14 |
| 2026-05-27 00:00 |
16:40:37.54 |
+22:52:40.6 |
HIP 81665 |
7.94 |
| 2026-05-27 12:00 |
16:40:31.58 |
+22:52:48.2 |
HIP 81665 |
8.88 |
| 2026-05-28 00:00 |
16:40:25.61 |
+22:52:55.3 |
HIP 81665 |
9.91 |
| 2026-05-28 12:00 |
16:40:19.64 |
+22:53:01.9 |
HIP 81665 |
11.02 |
| 2026-05-29 00:00 |
16:40:13.67 |
+22:53:08.1 |
HIP 81577 |
10.85 |
| 2026-05-29 12:00 |
16:40:07.70 |
+22:53:13.8 |
HIP 81577 |
9.77 |
| 2026-05-30 00:00 |
16:40:01.72 |
+22:53:19.0 |
HIP 81577 |
8.78 |
| 2026-05-30 12:00 |
16:39:55.75 |
+22:53:23.8 |
HIP 81577 |
7.91 |
| 2026-05-31 00:00 |
16:39:49.77 |
+22:53:28.1 |
HIP 81577 |
7.21 |
| 2026-05-31 12:00 |
16:39:43.79 |
+22:53:32.0 |
HIP 81577 |
6.73 |
| 2026-06-01 00:00 |
16:39:37.82 |
+22:53:35.4 |
HIP 81577 |
6.51 |
| 2026-06-01 12:00 |
16:39:31.84 |
+22:53:38.3 |
HIP 81575 |
6.55 |
| 2026-06-02 00:00 |
16:39:25.86 |
+22:53:40.7 |
HIP 81575 |
6.86 |