メタデータ
| 項目 |
値 |
| Designation |
438P/Christensen |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2005-04-11T20:00:18.210240Z |
| Orbit solution date (soln_date, UTC) |
2025-01-02T20:13:02Z |
| Obs used |
104 |
| NEO |
- |
| M1 |
17.100 |
| K1 |
6.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2020-07-31T10:04:40.224000Z |
| Discovery magnitude (MPC) |
22.50 G |
| Discovery observatory (MPC) |
G96 · Mt. Lemmon Survey |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2008-02-24.0000000 |
| e |
0.42227439 |
| q (au) |
2.209438 |
| a (au) |
3.824373 |
| i (deg) |
8.338405 |
| Ω (om, deg) |
260.613633 |
| ω (w, deg) |
58.380791 |
| M (ma, deg) |
138.131880 |
等級
散乱 + 全体線形
$$
M_a = (15.632 + 3.815\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
15.632 |
| n |
3.815 |
| gf |
1.000 |
| gb |
-0.930 |
| 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
ファインディングチャート
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
12:34:07.46 |
-13:24:58.8 |
HIP 61212 |
34.61 |
| 2026-05-12 12:00 |
12:33:55.76 |
-13:22:35.8 |
HIP 61296 |
33.19 |
| 2026-05-13 00:00 |
12:33:44.28 |
-13:20:13.6 |
HIP 61296 |
30.50 |
| 2026-05-13 12:00 |
12:33:33.03 |
-13:17:52.3 |
HIP 61296 |
28.05 |
| 2026-05-14 00:00 |
12:33:22.01 |
-13:15:32.0 |
HIP 61296 |
25.89 |
| 2026-05-14 12:00 |
12:33:11.22 |
-13:13:12.5 |
HIP 61296 |
24.05 |
| 2026-05-15 00:00 |
12:33:00.66 |
-13:10:54.0 |
HIP 61296 |
22.61 |
| 2026-05-15 12:00 |
12:32:50.33 |
-13:08:36.5 |
HIP 61296 |
21.62 |
| 2026-05-16 00:00 |
12:32:40.24 |
-13:06:20.0 |
HIP 61296 |
21.12 |
| 2026-05-16 12:00 |
12:32:30.39 |
-13:04:04.5 |
HIP 61296 |
21.11 |
| 2026-05-17 00:00 |
12:32:20.77 |
-13:01:50.0 |
HIP 61296 |
21.56 |
| 2026-05-17 12:00 |
12:32:11.40 |
-12:59:36.6 |
HIP 61153 |
19.38 |
| 2026-05-18 00:00 |
12:32:02.26 |
-12:57:24.3 |
HIP 61153 |
16.79 |
| 2026-05-18 12:00 |
12:31:53.37 |
-12:55:13.1 |
HIP 61153 |
14.45 |
| 2026-05-19 00:00 |
12:31:44.72 |
-12:53:03.0 |
HIP 61153 |
12.44 |
| 2026-05-19 12:00 |
12:31:36.32 |
-12:50:54.0 |
HIP 61153 |
10.91 |
| 2026-05-20 00:00 |
12:31:28.16 |
-12:48:46.3 |
HIP 61153 |
10.02 |
| 2026-05-20 12:00 |
12:31:20.24 |
-12:46:39.7 |
HIP 61153 |
9.90 |
| 2026-05-21 00:00 |
12:31:12.58 |
-12:44:34.3 |
HIP 61153 |
10.53 |
| 2026-05-21 12:00 |
12:31:05.16 |
-12:42:30.1 |
HIP 61153 |
11.76 |
| 2026-05-22 00:00 |
12:30:57.99 |
-12:40:27.2 |
HIP 61106 |
13.18 |
| 2026-05-22 12:00 |
12:30:51.08 |
-12:38:25.5 |
HIP 61106 |
12.46 |
| 2026-05-23 00:00 |
12:30:44.41 |
-12:36:25.0 |
HIP 61106 |
12.24 |
| 2026-05-23 12:00 |
12:30:37.99 |
-12:34:25.9 |
HIP 61106 |
12.51 |
| 2026-05-24 00:00 |
12:30:31.82 |
-12:32:28.0 |
HIP 61106 |
13.22 |
| 2026-05-24 12:00 |
12:30:25.91 |
-12:30:31.5 |
HIP 61106 |
14.27 |
| 2026-05-25 00:00 |
12:30:20.24 |
-12:28:36.3 |
HIP 61106 |
15.56 |
| 2026-05-25 12:00 |
12:30:14.83 |
-12:26:42.4 |
HIP 61106 |
17.02 |
| 2026-05-26 00:00 |
12:30:09.68 |
-12:24:49.8 |
HIP 61106 |
18.59 |
| 2026-05-26 12:00 |
12:30:04.77 |
-12:22:58.6 |
HIP 60981 |
19.11 |
| 2026-05-27 00:00 |
12:30:00.12 |
-12:21:08.8 |
HIP 60981 |
17.23 |
| 2026-05-27 12:00 |
12:29:55.72 |
-12:19:20.3 |
HIP 60981 |
15.43 |
| 2026-05-28 00:00 |
12:29:51.57 |
-12:17:33.3 |
HIP 60981 |
13.73 |
| 2026-05-28 12:00 |
12:29:47.68 |
-12:15:47.6 |
HIP 60981 |
12.16 |
| 2026-05-29 00:00 |
12:29:44.04 |
-12:14:03.4 |
HIP 60981 |
10.73 |
| 2026-05-29 12:00 |
12:29:40.66 |
-12:12:20.6 |
HIP 60981 |
9.47 |
| 2026-05-30 00:00 |
12:29:37.53 |
-12:10:39.2 |
HIP 60981 |
8.45 |
| 2026-05-30 12:00 |
12:29:34.65 |
-12:08:59.2 |
HIP 60981 |
7.71 |
| 2026-05-31 00:00 |
12:29:32.03 |
-12:07:20.7 |
HIP 60981 |
7.31 |
| 2026-05-31 12:00 |
12:29:29.66 |
-12:05:43.7 |
HIP 60981 |
7.27 |
| 2026-06-01 00:00 |
12:29:27.54 |
-12:04:08.1 |
HIP 60981 |
7.56 |
| 2026-06-01 12:00 |
12:29:25.68 |
-12:02:34.0 |
HIP 60981 |
8.13 |
| 2026-06-02 00:00 |
12:29:24.07 |
-12:01:01.4 |
HIP 60981 |
8.89 |