246P/NEAT
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) |
| 2026-02-03 00:00 |
06:04:59.80 |
+32:04:33.9 |
HIP 28890 |
14.51 |
| 2026-02-03 12:00 |
06:04:47.82 |
+32:04:39.8 |
HIP 28890 |
16.77 |
| 2026-02-04 00:00 |
06:04:36.06 |
+32:04:45.3 |
HIP 28890 |
19.06 |
| 2026-02-04 12:00 |
06:04:24.52 |
+32:04:50.2 |
HIP 28890 |
21.35 |
| 2026-02-05 00:00 |
06:04:13.20 |
+32:04:54.7 |
HIP 28890 |
23.63 |
| 2026-02-05 12:00 |
06:04:02.10 |
+32:04:58.6 |
HIP 28890 |
25.88 |
| 2026-02-06 00:00 |
06:03:51.22 |
+32:05:02.2 |
HIP 28890 |
28.10 |
| 2026-02-06 12:00 |
06:03:40.57 |
+32:05:05.3 |
HIP 28890 |
30.28 |
| 2026-02-07 00:00 |
06:03:30.14 |
+32:05:07.9 |
HIP 28626 |
32.32 |
| 2026-02-07 12:00 |
06:03:19.94 |
+32:05:10.1 |
HIP 28502 |
30.50 |
| 2026-02-08 00:00 |
06:03:09.96 |
+32:05:11.9 |
HIP 28502 |
28.47 |
| 2026-02-08 12:00 |
06:03:00.22 |
+32:05:13.3 |
HIP 28502 |
26.50 |
| 2026-02-09 00:00 |
06:02:50.70 |
+32:05:14.2 |
HIP 28502 |
24.59 |
| 2026-02-09 12:00 |
06:02:41.42 |
+32:05:14.8 |
HIP 28502 |
22.74 |
| 2026-02-10 00:00 |
06:02:32.36 |
+32:05:14.9 |
HIP 28502 |
20.97 |
| 2026-02-10 12:00 |
06:02:23.54 |
+32:05:14.7 |
HIP 28502 |
19.27 |
| 2026-02-11 00:00 |
06:02:14.96 |
+32:05:14.1 |
HIP 28502 |
17.65 |
| 2026-02-11 12:00 |
06:02:06.61 |
+32:05:13.1 |
HIP 28502 |
16.12 |
| 2026-02-12 00:00 |
06:01:58.49 |
+32:05:11.8 |
HIP 28502 |
14.69 |
| 2026-02-12 12:00 |
06:01:50.62 |
+32:05:10.1 |
HIP 28502 |
13.37 |
| 2026-02-13 00:00 |
06:01:42.98 |
+32:05:08.0 |
HIP 28502 |
12.17 |
| 2026-02-13 12:00 |
06:01:35.58 |
+32:05:05.6 |
HIP 28502 |
11.12 |
| 2026-02-14 00:00 |
06:01:28.42 |
+32:05:02.9 |
HIP 28477 |
9.83 |
| 2026-02-14 12:00 |
06:01:21.49 |
+32:04:59.9 |
HIP 28477 |
8.43 |
| 2026-02-15 00:00 |
06:01:14.81 |
+32:04:56.5 |
HIP 28477 |
7.11 |
| 2026-02-15 12:00 |
06:01:08.37 |
+32:04:52.9 |
HIP 28477 |
5.88 |
| 2026-02-16 00:00 |
06:01:02.18 |
+32:04:48.9 |
HIP 28477 |
4.78 |
| 2026-02-16 12:00 |
06:00:56.22 |
+32:04:44.6 |
HIP 28477 |
3.85 |
| 2026-02-17 00:00 |
06:00:50.51 |
+32:04:40.1 |
HIP 28477 |
3.19 |
| 2026-02-17 12:00 |
06:00:45.04 |
+32:04:35.2 |
HIP 28477 |
2.92 |
| 2026-02-18 00:00 |
06:00:39.82 |
+32:04:30.1 |
HIP 28477 |
3.09 |
| 2026-02-18 12:00 |
06:00:34.84 |
+32:04:24.7 |
HIP 28477 |
3.58 |
| 2026-02-19 00:00 |
06:00:30.11 |
+32:04:19.1 |
HIP 28477 |
4.25 |
| 2026-02-19 12:00 |
06:00:25.62 |
+32:04:13.2 |
HIP 28477 |
5.00 |
| 2026-02-20 00:00 |
06:00:21.38 |
+32:04:07.0 |
HIP 28477 |
5.77 |
| 2026-02-20 12:00 |
06:00:17.38 |
+32:04:00.7 |
HIP 28477 |
6.53 |
| 2026-02-21 00:00 |
06:00:13.62 |
+32:03:54.1 |
HIP 28477 |
7.27 |
| 2026-02-21 12:00 |
06:00:10.12 |
+32:03:47.2 |
HIP 28477 |
7.98 |
| 2026-02-22 00:00 |
06:00:06.86 |
+32:03:40.2 |
HIP 28477 |
8.65 |
| 2026-02-22 12:00 |
06:00:03.84 |
+32:03:32.9 |
HIP 28477 |
9.27 |
| 2026-02-23 00:00 |
06:00:01.07 |
+32:03:25.4 |
HIP 28477 |
9.86 |
| 2026-02-23 12:00 |
05:59:58.54 |
+32:03:17.7 |
HIP 28477 |
10.40 |
| 2026-02-24 00:00 |
05:59:56.26 |
+32:03:09.9 |
HIP 28477 |
10.90 |