メタデータ
| 項目 |
値 |
| Designation |
253P/PANSTARRS |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2018-05-07T16:43:41.024640Z |
| Orbit solution date (soln_date, UTC) |
2025-10-28T16:12:55Z |
| Obs used |
936 |
| NEO |
- |
| M1 |
8.000 |
| K1 |
29.750 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2019-05-04.0000000 |
| e |
0.41304705 |
| q (au) |
2.036337 |
| a (au) |
3.469336 |
| i (deg) |
4.940807 |
| Ω (om, deg) |
146.875124 |
| ω (w, deg) |
230.708050 |
| M (ma, deg) |
55.106908 |
等級
散乱 + 全体線形
$$
M_a = (14.139 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
14.139 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.655 |
| k |
0.800 |
| 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 |
| 2024-05-08 |
2025-02-03 |
+31.1826 |
-9.791 |
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 |
09:05:23.83 |
+16:49:17.9 |
HIP 44674 |
21.37 |
| 2026-05-12 12:00 |
09:05:41.36 |
+16:48:18.6 |
HIP 44674 |
20.15 |
| 2026-05-13 00:00 |
09:05:59.05 |
+16:47:18.3 |
HIP 44674 |
19.82 |
| 2026-05-13 12:00 |
09:06:16.90 |
+16:46:17.2 |
HIP 44773 |
20.08 |
| 2026-05-14 00:00 |
09:06:34.91 |
+16:45:15.2 |
HIP 44773 |
15.85 |
| 2026-05-14 12:00 |
09:06:53.08 |
+16:44:12.3 |
HIP 44773 |
11.73 |
| 2026-05-15 00:00 |
09:07:11.41 |
+16:43:08.5 |
HIP 44773 |
7.96 |
| 2026-05-15 12:00 |
09:07:29.89 |
+16:42:03.9 |
HIP 44773 |
5.46 |
| 2026-05-16 00:00 |
09:07:48.53 |
+16:40:58.4 |
HIP 44773 |
6.16 |
| 2026-05-16 12:00 |
09:08:07.33 |
+16:39:52.0 |
HIP 44870 |
6.81 |
| 2026-05-17 00:00 |
09:08:26.27 |
+16:38:44.8 |
HIP 44870 |
3.86 |
| 2026-05-17 12:00 |
09:08:45.37 |
+16:37:36.7 |
HIP 44870 |
5.23 |
| 2026-05-18 00:00 |
09:09:04.62 |
+16:36:27.8 |
HIP 44870 |
9.21 |
| 2026-05-18 12:00 |
09:09:24.01 |
+16:35:18.0 |
HIP 44894 |
13.19 |
| 2026-05-19 00:00 |
09:09:43.56 |
+16:34:07.4 |
HIP 44894 |
15.85 |
| 2026-05-19 12:00 |
09:10:03.24 |
+16:32:55.9 |
HIP 44894 |
19.39 |
| 2026-05-20 00:00 |
09:10:23.07 |
+16:31:43.6 |
HIP 44894 |
23.45 |
| 2026-05-20 12:00 |
09:10:43.04 |
+16:30:30.5 |
HIP 44894 |
27.81 |
| 2026-05-21 00:00 |
09:11:03.16 |
+16:29:16.5 |
HIP 45201 |
23.35 |
| 2026-05-21 12:00 |
09:11:23.41 |
+16:28:01.8 |
HIP 45201 |
18.71 |
| 2026-05-22 00:00 |
09:11:43.80 |
+16:26:46.2 |
HIP 45201 |
14.30 |
| 2026-05-22 12:00 |
09:12:04.32 |
+16:25:29.8 |
HIP 45201 |
10.47 |
| 2026-05-23 00:00 |
09:12:24.98 |
+16:24:12.6 |
HIP 45201 |
8.14 |
| 2026-05-23 12:00 |
09:12:45.77 |
+16:22:54.7 |
HIP 45201 |
8.69 |
| 2026-05-24 00:00 |
09:13:06.70 |
+16:21:35.9 |
HIP 45201 |
11.77 |
| 2026-05-24 12:00 |
09:13:27.75 |
+16:20:16.3 |
HIP 45201 |
16.02 |
| 2026-05-25 00:00 |
09:13:48.93 |
+16:18:56.0 |
HIP 45201 |
20.74 |
| 2026-05-25 12:00 |
09:14:10.24 |
+16:17:34.8 |
HIP 45387 |
20.73 |
| 2026-05-26 00:00 |
09:14:31.68 |
+16:16:12.9 |
HIP 45387 |
17.13 |
| 2026-05-26 12:00 |
09:14:53.24 |
+16:14:50.2 |
HIP 45387 |
14.60 |
| 2026-05-27 00:00 |
09:15:14.92 |
+16:13:26.8 |
HIP 45387 |
13.79 |
| 2026-05-27 12:00 |
09:15:36.72 |
+16:12:02.5 |
HIP 45387 |
15.03 |
| 2026-05-28 00:00 |
09:15:58.65 |
+16:10:37.6 |
HIP 45387 |
17.91 |
| 2026-05-28 12:00 |
09:16:20.69 |
+16:09:11.8 |
HIP 45387 |
21.82 |
| 2026-05-29 00:00 |
09:16:42.86 |
+16:07:45.3 |
HIP 45387 |
26.32 |
| 2026-05-29 12:00 |
09:17:05.14 |
+16:06:18.1 |
HIP 45579 |
27.08 |
| 2026-05-30 00:00 |
09:17:27.53 |
+16:04:50.1 |
HIP 45579 |
28.27 |
| 2026-05-30 12:00 |
09:17:50.04 |
+16:03:21.4 |
HIP 45579 |
30.46 |
| 2026-05-31 00:00 |
09:18:12.66 |
+16:01:51.9 |
HIP 45777 |
26.76 |
| 2026-05-31 12:00 |
09:18:35.40 |
+16:00:21.7 |
HIP 45777 |
21.11 |
| 2026-06-01 00:00 |
09:18:58.25 |
+15:58:50.8 |
HIP 45777 |
15.43 |
| 2026-06-01 12:00 |
09:19:21.20 |
+15:57:19.1 |
HIP 45777 |
9.75 |
| 2026-06-02 00:00 |
09:19:44.27 |
+15:55:46.7 |
HIP 45777 |
4.18 |