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
$$
M_a = (6.726 + 4.555\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
6.726 |
| n |
4.555 |
| gf |
0.943 |
| gb |
-0.999 |
| 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 |
+4.2939 |
-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) |
| 2026-03-26 00:00 |
06:04:47.33 |
+31:52:03.3 |
HIP 28890 |
15.87 |
| 2026-03-26 12:00 |
06:04:58.85 |
+31:51:50.7 |
HIP 28890 |
13.65 |
| 2026-03-27 00:00 |
06:05:10.58 |
+31:51:38.0 |
HIP 28890 |
11.49 |
| 2026-03-27 12:00 |
06:05:22.50 |
+31:51:25.3 |
HIP 28890 |
9.46 |
| 2026-03-28 00:00 |
06:05:34.61 |
+31:51:12.7 |
HIP 28890 |
7.70 |
| 2026-03-28 12:00 |
06:05:46.92 |
+31:51:00.0 |
HIP 28890 |
6.51 |
| 2026-03-29 00:00 |
06:05:59.43 |
+31:50:47.2 |
HIP 28890 |
6.26 |
| 2026-03-29 12:00 |
06:06:12.12 |
+31:50:34.5 |
HIP 28890 |
7.10 |
| 2026-03-30 00:00 |
06:06:25.01 |
+31:50:21.7 |
HIP 28890 |
8.76 |
| 2026-03-30 12:00 |
06:06:38.08 |
+31:50:08.9 |
HIP 28919 |
10.77 |
| 2026-03-31 00:00 |
06:06:51.35 |
+31:49:56.1 |
HIP 28919 |
12.45 |
| 2026-03-31 12:00 |
06:07:04.80 |
+31:49:43.3 |
HIP 28919 |
14.51 |
| 2026-04-01 00:00 |
06:07:18.44 |
+31:49:30.4 |
HIP 28919 |
16.84 |
| 2026-04-01 12:00 |
06:07:32.27 |
+31:49:17.5 |
HIP 28919 |
19.36 |
| 2026-04-02 00:00 |
06:07:46.27 |
+31:49:04.6 |
HIP 29173 |
19.30 |
| 2026-04-02 12:00 |
06:08:00.47 |
+31:48:51.7 |
HIP 29173 |
16.35 |
| 2026-04-03 00:00 |
06:08:14.84 |
+31:48:38.8 |
HIP 29173 |
13.38 |
| 2026-04-03 12:00 |
06:08:29.39 |
+31:48:25.8 |
HIP 29173 |
10.44 |
| 2026-04-04 00:00 |
06:08:44.13 |
+31:48:12.8 |
HIP 29173 |
7.59 |
| 2026-04-04 12:00 |
06:08:59.04 |
+31:47:59.8 |
HIP 29173 |
5.07 |
| 2026-04-05 00:00 |
06:09:14.13 |
+31:47:46.7 |
HIP 29173 |
3.74 |
| 2026-04-05 12:00 |
06:09:29.40 |
+31:47:33.6 |
HIP 29173 |
4.81 |
| 2026-04-06 00:00 |
06:09:44.84 |
+31:47:20.5 |
HIP 29173 |
7.35 |
| 2026-04-06 12:00 |
06:10:00.46 |
+31:47:07.4 |
HIP 29173 |
10.35 |
| 2026-04-07 00:00 |
06:10:16.25 |
+31:46:54.2 |
HIP 29173 |
13.55 |
| 2026-04-07 12:00 |
06:10:32.21 |
+31:46:41.0 |
HIP 29302 |
16.29 |
| 2026-04-08 00:00 |
06:10:48.35 |
+31:46:27.7 |
HIP 29302 |
16.55 |
| 2026-04-08 12:00 |
06:11:04.65 |
+31:46:14.5 |
HIP 29302 |
17.50 |
| 2026-04-09 00:00 |
06:11:21.13 |
+31:46:01.2 |
HIP 29302 |
19.06 |
| 2026-04-09 12:00 |
06:11:37.77 |
+31:45:47.8 |
HIP 29302 |
21.12 |
| 2026-04-10 00:00 |
06:11:54.58 |
+31:45:34.4 |
HIP 29302 |
23.55 |
| 2026-04-10 12:00 |
06:12:11.56 |
+31:45:21.0 |
HIP 29302 |
26.28 |
| 2026-04-11 00:00 |
06:12:28.71 |
+31:45:07.5 |
HIP 29302 |
29.22 |
| 2026-04-11 12:00 |
06:12:46.01 |
+31:44:54.0 |
HIP 29302 |
32.34 |
| 2026-04-12 00:00 |
06:13:03.48 |
+31:44:40.5 |
HIP 29688 |
32.51 |
| 2026-04-12 12:00 |
06:13:21.12 |
+31:44:26.9 |
HIP 29688 |
29.20 |
| 2026-04-13 00:00 |
06:13:38.91 |
+31:44:13.2 |
HIP 29688 |
25.98 |
| 2026-04-13 12:00 |
06:13:56.87 |
+31:43:59.5 |
HIP 29688 |
22.92 |
| 2026-04-14 00:00 |
06:14:14.98 |
+31:43:45.8 |
HIP 29688 |
20.09 |
| 2026-04-14 12:00 |
06:14:33.25 |
+31:43:32.0 |
HIP 29688 |
17.65 |
| 2026-04-15 00:00 |
06:14:51.68 |
+31:43:18.1 |
HIP 29688 |
15.79 |
| 2026-04-15 12:00 |
06:15:10.27 |
+31:43:04.2 |
HIP 29688 |
14.76 |
| 2026-04-16 00:00 |
06:15:29.01 |
+31:42:50.3 |
HIP 29688 |
14.76 |