メタデータ
| 項目 |
値 |
| Designation |
502P/NEAT |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2025-08-05T14:59:17.733120Z |
| Orbit solution date (soln_date, UTC) |
2026-07-06T12:12:52Z |
| Obs used |
285 |
| NEO |
- |
| M1 |
7.200 |
| K1 |
15.000 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2025-04-23T10:52:57.561600Z |
| Discovery magnitude (MPC) |
20.32 G |
| Discovery observatory (MPC) |
G96 · University of Arizona Mt. Lemmon Survey |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2017-11-21.0000000 |
| e |
0.47102338 |
| q (au) |
4.258706 |
| a (au) |
8.050839 |
| i (deg) |
11.386914 |
| Ω (om, deg) |
264.577075 |
| ω (w, deg) |
37.190362 |
| M (ma, deg) |
238.559700 |
等級
散乱 + 全体線形
$$
M_a = (10.043 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
10.043 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.725 |
| k |
0.800 |
| δ90 |
9.999 |
| 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 |
| 2024-07-01 |
2025-08-05 |
+24.7671 |
-15.558 |
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) |
| 2026-07-29 00:00 |
23:31:28.52 |
+11:22:31.8 |
HIP 116156 |
12.80 |
| 2026-07-29 12:00 |
23:31:23.58 |
+11:23:19.1 |
HIP 116156 |
13.26 |
| 2026-07-30 00:00 |
23:31:18.47 |
+11:24:04.8 |
HIP 116156 |
13.91 |
| 2026-07-30 12:00 |
23:31:13.18 |
+11:24:49.0 |
HIP 116156 |
14.72 |
| 2026-07-31 00:00 |
23:31:07.72 |
+11:25:31.7 |
HIP 116156 |
15.69 |
| 2026-07-31 12:00 |
23:31:02.08 |
+11:26:12.8 |
HIP 116156 |
16.78 |
| 2026-08-01 00:00 |
23:30:56.27 |
+11:26:52.4 |
HIP 116156 |
17.99 |
| 2026-08-01 12:00 |
23:30:50.29 |
+11:27:30.5 |
HIP 116156 |
19.29 |
| 2026-08-02 00:00 |
23:30:44.14 |
+11:28:06.9 |
HIP 115978 |
17.94 |
| 2026-08-02 12:00 |
23:30:37.82 |
+11:28:41.8 |
HIP 115978 |
16.45 |
| 2026-08-03 00:00 |
23:30:31.32 |
+11:29:15.1 |
HIP 115978 |
14.98 |
| 2026-08-03 12:00 |
23:30:24.67 |
+11:29:46.9 |
HIP 115978 |
13.56 |
| 2026-08-04 00:00 |
23:30:17.84 |
+11:30:17.1 |
HIP 115978 |
12.21 |
| 2026-08-04 12:00 |
23:30:10.85 |
+11:30:45.6 |
HIP 115978 |
10.99 |
| 2026-08-05 00:00 |
23:30:03.69 |
+11:31:12.6 |
HIP 115978 |
9.95 |
| 2026-08-05 12:00 |
23:29:56.37 |
+11:31:38.0 |
HIP 115978 |
9.17 |
| 2026-08-06 00:00 |
23:29:48.89 |
+11:32:01.9 |
HIP 115978 |
8.74 |
| 2026-08-06 12:00 |
23:29:41.25 |
+11:32:24.1 |
HIP 115978 |
8.75 |
| 2026-08-07 00:00 |
23:29:33.44 |
+11:32:44.7 |
HIP 115978 |
9.21 |
| 2026-08-07 12:00 |
23:29:25.48 |
+11:33:03.7 |
HIP 115889 |
9.95 |
| 2026-08-08 00:00 |
23:29:17.36 |
+11:33:21.1 |
HIP 115889 |
8.12 |
| 2026-08-08 12:00 |
23:29:09.08 |
+11:33:36.8 |
HIP 115889 |
6.35 |
| 2026-08-09 00:00 |
23:29:00.65 |
+11:33:51.0 |
HIP 115889 |
4.75 |
| 2026-08-09 12:00 |
23:28:52.07 |
+11:34:03.5 |
HIP 115889 |
3.64 |
| 2026-08-10 00:00 |
23:28:43.33 |
+11:34:14.5 |
HIP 115889 |
3.56 |
| 2026-08-10 12:00 |
23:28:34.44 |
+11:34:23.8 |
HIP 115889 |
4.62 |
| 2026-08-11 00:00 |
23:28:25.41 |
+11:34:31.5 |
HIP 115889 |
6.30 |
| 2026-08-11 12:00 |
23:28:16.23 |
+11:34:37.6 |
HIP 115889 |
8.26 |
| 2026-08-12 00:00 |
23:28:06.90 |
+11:34:42.0 |
HIP 115889 |
10.36 |
| 2026-08-12 12:00 |
23:27:57.43 |
+11:34:44.9 |
HIP 115889 |
12.55 |
| 2026-08-13 00:00 |
23:27:47.82 |
+11:34:46.1 |
HIP 115889 |
14.81 |
| 2026-08-13 12:00 |
23:27:38.07 |
+11:34:45.7 |
HIP 115889 |
17.12 |
| 2026-08-14 00:00 |
23:27:28.18 |
+11:34:43.7 |
HIP 115889 |
19.47 |
| 2026-08-14 12:00 |
23:27:18.16 |
+11:34:40.1 |
HIP 115889 |
21.87 |
| 2026-08-15 00:00 |
23:27:08.00 |
+11:34:34.8 |
HIP 115889 |
24.31 |
| 2026-08-15 12:00 |
23:26:57.71 |
+11:34:28.0 |
HIP 115889 |
26.78 |
| 2026-08-16 00:00 |
23:26:47.30 |
+11:34:19.6 |
HIP 115889 |
29.29 |
| 2026-08-16 12:00 |
23:26:36.75 |
+11:34:09.5 |
HIP 115607 |
27.46 |
| 2026-08-17 00:00 |
23:26:26.08 |
+11:33:57.9 |
HIP 115607 |
25.35 |
| 2026-08-17 12:00 |
23:26:15.29 |
+11:33:44.7 |
HIP 115607 |
23.30 |
| 2026-08-18 00:00 |
23:26:04.38 |
+11:33:29.9 |
HIP 115607 |
21.34 |
| 2026-08-18 12:00 |
23:25:53.35 |
+11:33:13.6 |
HIP 115607 |
19.53 |
| 2026-08-19 00:00 |
23:25:42.21 |
+11:32:55.6 |
HIP 115607 |
17.90 |