メタデータ
| 項目 |
値 |
| Designation |
239P/LINEAR |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2019-01-09T23:17:42.864000Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:28:01Z |
| Obs used |
365 |
| NEO |
- |
| M1 |
15.300 |
| K1 |
13.250 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2016-10-04.0000000 |
| e |
0.63143654 |
| q (au) |
1.647599 |
| a (au) |
4.470327 |
| i (deg) |
11.305620 |
| Ω (om, deg) |
255.944518 |
| ω (w, deg) |
220.383718 |
| M (ma, deg) |
273.660407 |
等級
散乱 + 全体線形
$$
M_a = (18.785 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
18.785 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.656 |
| 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 |
| 2018-10-08 |
2019-01-09 |
+4.7782 |
-0.935 |
| 2019-01-11 |
2019-04-18 |
-10.8877 |
+2.304 |
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 |
22:08:19.26 |
-01:23:19.8 |
HIP 109141 |
27.92 |
| 2026-03-26 12:00 |
22:08:38.26 |
-01:21:04.7 |
HIP 109141 |
32.26 |
| 2026-03-27 00:00 |
22:08:57.21 |
-01:18:49.5 |
HIP 109141 |
36.82 |
| 2026-03-27 12:00 |
22:09:16.11 |
-01:16:34.1 |
HIP 109571 |
37.93 |
| 2026-03-28 00:00 |
22:09:34.95 |
-01:14:18.7 |
HIP 109571 |
33.17 |
| 2026-03-28 12:00 |
22:09:53.74 |
-01:12:03.1 |
HIP 109560 |
28.19 |
| 2026-03-29 00:00 |
22:10:12.48 |
-01:09:47.5 |
HIP 109560 |
22.99 |
| 2026-03-29 12:00 |
22:10:31.17 |
-01:07:31.8 |
HIP 109560 |
17.81 |
| 2026-03-30 00:00 |
22:10:49.80 |
-01:05:15.9 |
HIP 109560 |
12.63 |
| 2026-03-30 12:00 |
22:11:08.37 |
-01:03:00.0 |
HIP 109560 |
7.48 |
| 2026-03-31 00:00 |
22:11:26.89 |
-01:00:44.0 |
HIP 109560 |
2.38 |
| 2026-03-31 12:00 |
22:11:45.36 |
-00:58:28.0 |
HIP 109560 |
2.92 |
| 2026-04-01 00:00 |
22:12:03.76 |
-00:56:11.8 |
HIP 109560 |
8.01 |
| 2026-04-01 12:00 |
22:12:22.11 |
-00:53:55.6 |
HIP 109560 |
13.11 |
| 2026-04-02 00:00 |
22:12:40.41 |
-00:51:39.3 |
HIP 109560 |
18.22 |
| 2026-04-02 12:00 |
22:12:58.64 |
-00:49:23.0 |
HIP 109777 |
20.13 |
| 2026-04-03 00:00 |
22:13:16.81 |
-00:47:06.6 |
HIP 109777 |
15.06 |
| 2026-04-03 12:00 |
22:13:34.93 |
-00:44:50.1 |
HIP 109777 |
10.01 |
| 2026-04-04 00:00 |
22:13:52.98 |
-00:42:33.6 |
HIP 109777 |
5.00 |
| 2026-04-04 12:00 |
22:14:10.98 |
-00:40:17.1 |
HIP 109777 |
0.94 |
| 2026-04-05 00:00 |
22:14:28.91 |
-00:38:00.5 |
HIP 109777 |
5.24 |
| 2026-04-05 12:00 |
22:14:46.78 |
-00:35:43.9 |
HIP 109777 |
10.21 |
| 2026-04-06 00:00 |
22:15:04.58 |
-00:33:27.2 |
HIP 109835 |
14.63 |
| 2026-04-06 12:00 |
22:15:22.33 |
-00:31:10.5 |
HIP 109835 |
18.49 |
| 2026-04-07 00:00 |
22:15:40.00 |
-00:28:53.8 |
HIP 109835 |
22.79 |
| 2026-04-07 12:00 |
22:15:57.62 |
-00:26:37.1 |
HIP 109835 |
27.30 |
| 2026-04-08 00:00 |
22:16:15.17 |
-00:24:20.4 |
HIP 109927 |
27.08 |
| 2026-04-08 12:00 |
22:16:32.65 |
-00:22:03.6 |
HIP 110091 |
24.21 |
| 2026-04-09 00:00 |
22:16:50.06 |
-00:19:46.9 |
HIP 110091 |
19.36 |
| 2026-04-09 12:00 |
22:17:07.41 |
-00:17:30.1 |
HIP 110091 |
14.59 |
| 2026-04-10 00:00 |
22:17:24.69 |
-00:15:13.3 |
HIP 110091 |
9.95 |
| 2026-04-10 12:00 |
22:17:41.90 |
-00:12:56.6 |
HIP 110091 |
5.75 |
| 2026-04-11 00:00 |
22:17:59.04 |
-00:10:39.9 |
HIP 110091 |
3.82 |
| 2026-04-11 12:00 |
22:18:16.11 |
-00:08:23.2 |
HIP 110091 |
6.57 |
| 2026-04-12 00:00 |
22:18:33.10 |
-00:06:06.5 |
HIP 110091 |
10.87 |
| 2026-04-12 12:00 |
22:18:50.03 |
-00:03:49.8 |
HIP 110091 |
15.47 |
| 2026-04-13 00:00 |
22:19:06.88 |
-00:01:33.2 |
HIP 110091 |
20.15 |
| 2026-04-13 12:00 |
22:19:23.66 |
+00:00:43.4 |
HIP 110302 |
17.04 |
| 2026-04-14 00:00 |
22:19:40.36 |
+00:02:59.9 |
HIP 110302 |
14.04 |
| 2026-04-14 12:00 |
22:19:56.99 |
+00:05:16.4 |
HIP 110302 |
12.22 |
| 2026-04-15 00:00 |
22:20:13.55 |
+00:07:32.8 |
HIP 110302 |
12.12 |
| 2026-04-15 12:00 |
22:20:30.02 |
+00:09:49.2 |
HIP 110302 |
13.74 |
| 2026-04-16 00:00 |
22:20:46.42 |
+00:12:05.4 |
HIP 110302 |
16.58 |