メタデータ
| 項目 |
値 |
| Designation |
246P/NEAT |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2013-01-28T15:13:27.269760Z |
| Orbit solution date (soln_date, UTC) |
2024-12-26T20:12:42Z |
| Obs used |
4914 |
| NEO |
- |
| M1 |
5.900 |
| K1 |
14.750 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2013-05-21.0000000 |
| e |
0.28504446 |
| q (au) |
2.879720 |
| a (au) |
4.027832 |
| i (deg) |
15.971716 |
| Ω (om, deg) |
78.780536 |
| ω (w, deg) |
176.171718 |
| M (ma, deg) |
13.700320 |
等級
散乱 + 全体線形
$$
M_a = (6.725 + 4.555\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
6.725 |
| n |
4.555 |
| gf |
0.995 |
| gb |
-0.502 |
| 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
残差 (区間線形)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| 開始日 (UTC) |
終了日 (UTC) |
a |
b |
| 2018-12-16 |
2020-04-22 |
-9.1189 |
+4.406 |
| 2020-04-22 |
2021-02-25 |
+4.2940 |
-2.300 |
| 2021-02-25 |
2019-09-03 |
+3.5698 |
-2.201 |
| 2019-09-03 |
2024-12-07 |
+8.2838 |
-4.696 |
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 |
08:43:11.02 |
+29:05:59.4 |
HIP 42699 |
29.72 |
| 2026-09-20 12:00 |
08:43:36.58 |
+29:05:41.0 |
HIP 42978 |
27.49 |
| 2026-09-21 00:00 |
08:44:02.05 |
+29:05:23.1 |
HIP 42978 |
22.58 |
| 2026-09-21 12:00 |
08:44:27.42 |
+29:05:05.7 |
HIP 42978 |
18.07 |
| 2026-09-22 00:00 |
08:44:52.71 |
+29:04:48.8 |
HIP 42978 |
14.32 |
| 2026-09-22 12:00 |
08:45:17.90 |
+29:04:32.5 |
HIP 42978 |
12.01 |
| 2026-09-23 00:00 |
08:45:42.99 |
+29:04:16.7 |
HIP 42978 |
12.00 |
| 2026-09-23 12:00 |
08:46:07.99 |
+29:04:01.4 |
HIP 42978 |
14.26 |
| 2026-09-24 00:00 |
08:46:32.89 |
+29:03:46.8 |
HIP 43145 |
9.84 |
| 2026-09-24 12:00 |
08:46:57.70 |
+29:03:32.6 |
HIP 43145 |
5.09 |
| 2026-09-25 00:00 |
08:47:22.41 |
+29:03:19.1 |
HIP 43145 |
3.68 |
| 2026-09-25 12:00 |
08:47:47.02 |
+29:03:06.1 |
HIP 43145 |
7.70 |
| 2026-09-26 00:00 |
08:48:11.53 |
+29:02:53.7 |
HIP 43274 |
10.71 |
| 2026-09-26 12:00 |
08:48:35.94 |
+29:02:41.9 |
HIP 43274 |
5.98 |
| 2026-09-27 00:00 |
08:49:00.25 |
+29:02:30.7 |
HIP 43274 |
3.72 |
| 2026-09-27 12:00 |
08:49:24.46 |
+29:02:20.1 |
HIP 43274 |
6.95 |
| 2026-09-28 00:00 |
08:49:48.56 |
+29:02:10.1 |
HIP 43274 |
11.77 |
| 2026-09-28 12:00 |
08:50:12.56 |
+29:02:00.7 |
HIP 43274 |
16.84 |
| 2026-09-29 00:00 |
08:50:36.46 |
+29:01:51.9 |
HIP 43551 |
21.38 |
| 2026-09-29 12:00 |
08:51:00.26 |
+29:01:43.8 |
HIP 43551 |
16.52 |
| 2026-09-30 00:00 |
08:51:23.94 |
+29:01:36.3 |
HIP 43551 |
11.98 |
| 2026-09-30 12:00 |
08:51:47.53 |
+29:01:29.4 |
HIP 43551 |
8.21 |
| 2026-10-01 00:00 |
08:52:11.00 |
+29:01:23.2 |
HIP 43551 |
6.66 |
| 2026-10-01 12:00 |
08:52:34.36 |
+29:01:17.6 |
HIP 43551 |
8.58 |
| 2026-10-02 00:00 |
08:52:57.62 |
+29:01:12.8 |
HIP 43551 |
12.42 |
| 2026-10-02 12:00 |
08:53:20.76 |
+29:01:08.5 |
HIP 43551 |
16.91 |
| 2026-10-03 00:00 |
08:53:43.80 |
+29:01:05.0 |
HIP 43628 |
20.74 |
| 2026-10-03 12:00 |
08:54:06.72 |
+29:01:02.2 |
HIP 43628 |
23.11 |
| 2026-10-04 00:00 |
08:54:29.52 |
+29:01:00.0 |
HIP 43628 |
26.23 |
| 2026-10-04 12:00 |
08:54:52.21 |
+29:00:58.6 |
HIP 43882 |
28.83 |
| 2026-10-05 00:00 |
08:55:14.79 |
+29:00:57.9 |
HIP 43882 |
25.66 |
| 2026-10-05 12:00 |
08:55:37.25 |
+29:00:57.8 |
HIP 43952 |
22.92 |
| 2026-10-06 00:00 |
08:55:59.59 |
+29:00:58.6 |
HIP 43952 |
18.93 |
| 2026-10-06 12:00 |
08:56:21.81 |
+29:01:00.0 |
HIP 43952 |
15.46 |
| 2026-10-07 00:00 |
08:56:43.91 |
+29:01:02.2 |
HIP 43952 |
12.91 |
| 2026-10-07 12:00 |
08:57:05.89 |
+29:01:05.2 |
HIP 43952 |
11.87 |
| 2026-10-08 00:00 |
08:57:27.75 |
+29:01:08.9 |
HIP 43952 |
12.67 |
| 2026-10-08 12:00 |
08:57:49.48 |
+29:01:13.4 |
HIP 43952 |
15.00 |
| 2026-10-09 00:00 |
08:58:11.09 |
+29:01:18.6 |
HIP 43952 |
18.26 |
| 2026-10-09 12:00 |
08:58:32.57 |
+29:01:24.6 |
HIP 43952 |
22.03 |
| 2026-10-10 00:00 |
08:58:53.93 |
+29:01:31.4 |
HIP 43952 |
26.06 |
| 2026-10-10 12:00 |
08:59:15.16 |
+29:01:39.1 |
HIP 44211 |
25.87 |
| 2026-10-11 00:00 |
08:59:36.25 |
+29:01:47.5 |
HIP 44211 |
23.75 |