メタデータ
| 項目 |
値 |
| Designation |
90P/Gehrels 1 |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2017-06-19T06:36:36.149760Z |
| Orbit solution date (soln_date, UTC) |
2022-05-24T23:57:55Z |
| Obs used |
577 |
| NEO |
- |
| M1 |
7.000 |
| K1 |
18.000 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2017-02-16.0000000 |
| e |
0.50979286 |
| q (au) |
2.974897 |
| a (au) |
6.068654 |
| i (deg) |
9.635376 |
| Ω (om, deg) |
13.251828 |
| ω (w, deg) |
29.270027 |
| M (ma, deg) |
351.872780 |
等級
散乱 + 全体線形
$$
M_a = (8.608 + 4.725\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
8.608 |
| n |
4.725 |
| gf |
1.000 |
| gb |
-0.828 |
| 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 |
| 2016-08-27 |
2017-01-18 |
+56.4715 |
-28.048 |
| 2017-07-30 |
2018-04-15 |
-5.8039 |
+3.002 |
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 |
15:26:11.31 |
-26:18:28.2 |
HIP 75480 |
21.20 |
| 2026-05-12 12:00 |
15:25:59.02 |
-26:17:55.4 |
HIP 75480 |
19.96 |
| 2026-05-13 00:00 |
15:25:46.72 |
-26:17:22.1 |
HIP 75480 |
19.07 |
| 2026-05-13 12:00 |
15:25:34.41 |
-26:16:48.6 |
HIP 75480 |
18.57 |
| 2026-05-14 00:00 |
15:25:22.10 |
-26:16:14.7 |
HIP 75480 |
18.49 |
| 2026-05-14 12:00 |
15:25:09.78 |
-26:15:40.4 |
HIP 75480 |
18.84 |
| 2026-05-15 00:00 |
15:24:57.46 |
-26:15:05.8 |
HIP 75480 |
19.60 |
| 2026-05-15 12:00 |
15:24:45.14 |
-26:14:30.9 |
HIP 75480 |
20.72 |
| 2026-05-16 00:00 |
15:24:32.82 |
-26:13:55.7 |
HIP 75480 |
22.15 |
| 2026-05-16 12:00 |
15:24:20.51 |
-26:13:20.2 |
HIP 75480 |
23.84 |
| 2026-05-17 00:00 |
15:24:08.20 |
-26:12:44.4 |
HIP 75480 |
25.73 |
| 2026-05-17 12:00 |
15:23:55.89 |
-26:12:08.3 |
HIP 75408 |
27.36 |
| 2026-05-18 00:00 |
15:23:43.60 |
-26:11:31.8 |
HIP 75408 |
27.66 |
| 2026-05-18 12:00 |
15:23:31.31 |
-26:10:55.1 |
HIP 75408 |
28.23 |
| 2026-05-19 00:00 |
15:23:19.03 |
-26:10:18.1 |
HIP 75408 |
29.07 |
| 2026-05-19 12:00 |
15:23:06.77 |
-26:09:40.9 |
HIP 75408 |
30.14 |
| 2026-05-20 00:00 |
15:22:54.52 |
-26:09:03.3 |
HIP 75092 |
31.41 |
| 2026-05-20 12:00 |
15:22:42.28 |
-26:08:25.5 |
HIP 75092 |
28.60 |
| 2026-05-21 00:00 |
15:22:30.07 |
-26:07:47.4 |
HIP 75092 |
25.80 |
| 2026-05-21 12:00 |
15:22:17.87 |
-26:07:09.1 |
HIP 75092 |
23.00 |
| 2026-05-22 00:00 |
15:22:05.69 |
-26:06:30.5 |
HIP 75092 |
20.21 |
| 2026-05-22 12:00 |
15:21:53.53 |
-26:05:51.7 |
HIP 75092 |
17.43 |
| 2026-05-23 00:00 |
15:21:41.40 |
-26:05:12.7 |
HIP 75092 |
14.67 |
| 2026-05-23 12:00 |
15:21:29.29 |
-26:04:33.4 |
HIP 75092 |
11.92 |
| 2026-05-24 00:00 |
15:21:17.21 |
-26:03:53.9 |
HIP 75092 |
9.21 |
| 2026-05-24 12:00 |
15:21:05.16 |
-26:03:14.1 |
HIP 75092 |
6.56 |
| 2026-05-25 00:00 |
15:20:53.13 |
-26:02:34.2 |
HIP 75092 |
4.12 |
| 2026-05-25 12:00 |
15:20:41.14 |
-26:01:54.0 |
HIP 75092 |
2.50 |
| 2026-05-26 00:00 |
15:20:29.17 |
-26:01:13.7 |
HIP 75092 |
3.31 |
| 2026-05-26 12:00 |
15:20:17.24 |
-26:00:33.1 |
HIP 75092 |
5.56 |
| 2026-05-27 00:00 |
15:20:05.35 |
-25:59:52.4 |
HIP 75092 |
8.12 |
| 2026-05-27 12:00 |
15:19:53.49 |
-25:59:11.5 |
HIP 75092 |
10.78 |
| 2026-05-28 00:00 |
15:19:41.67 |
-25:58:30.4 |
HIP 75092 |
13.46 |
| 2026-05-28 12:00 |
15:19:29.88 |
-25:57:49.1 |
HIP 75092 |
16.16 |
| 2026-05-29 00:00 |
15:19:18.14 |
-25:57:07.6 |
HIP 75092 |
18.86 |
| 2026-05-29 12:00 |
15:19:06.44 |
-25:56:26.0 |
HIP 75092 |
21.56 |
| 2026-05-30 00:00 |
15:18:54.78 |
-25:55:44.3 |
HIP 74912 |
23.24 |
| 2026-05-30 12:00 |
15:18:43.16 |
-25:55:02.3 |
HIP 74912 |
22.12 |
| 2026-05-31 00:00 |
15:18:31.59 |
-25:54:20.3 |
HIP 74912 |
21.29 |
| 2026-05-31 12:00 |
15:18:20.07 |
-25:53:38.1 |
HIP 74912 |
20.78 |
| 2026-06-01 00:00 |
15:18:08.59 |
-25:52:55.8 |
HIP 74912 |
20.60 |
| 2026-06-01 12:00 |
15:17:57.16 |
-25:52:13.3 |
HIP 74912 |
20.76 |
| 2026-06-02 00:00 |
15:17:45.79 |
-25:51:30.8 |
HIP 74912 |
21.25 |