メタデータ
| 項目 |
値 |
| Designation |
C/2014 W7 (Christensen) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2014-12-31T14:55:39.754560Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:03Z |
| Obs used |
46 |
| NEO |
- |
| M1 |
16.300 |
| K1 |
10.000 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2014-12-11.0000000 |
| e |
0.86930062 |
| q (au) |
1.488259 |
| a (au) |
11.386888 |
| i (deg) |
98.313749 |
| Ω (om, deg) |
151.260997 |
| ω (w, deg) |
33.240158 |
| M (ma, deg) |
359.471035 |
等級
散乱 + 全体線形
$$
M_a = (16.710 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
16.710 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.988 |
| 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
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
22:43:23.54 |
-33:16:02.9 |
HIP 112237 |
14.03 |
| 2026-07-29 12:00 |
22:43:17.74 |
-33:17:01.0 |
HIP 112237 |
13.99 |
| 2026-07-30 00:00 |
22:43:11.89 |
-33:17:58.9 |
HIP 112237 |
14.12 |
| 2026-07-30 12:00 |
22:43:06.01 |
-33:18:56.7 |
HIP 112237 |
14.43 |
| 2026-07-31 00:00 |
22:43:00.10 |
-33:19:54.3 |
HIP 112237 |
14.90 |
| 2026-07-31 12:00 |
22:42:54.15 |
-33:20:51.8 |
HIP 112237 |
15.52 |
| 2026-08-01 00:00 |
22:42:48.16 |
-33:21:49.1 |
HIP 112077 |
15.52 |
| 2026-08-01 12:00 |
22:42:42.14 |
-33:22:46.2 |
HIP 112077 |
14.02 |
| 2026-08-02 00:00 |
22:42:36.09 |
-33:23:43.2 |
HIP 112077 |
12.54 |
| 2026-08-02 12:00 |
22:42:30.00 |
-33:24:40.1 |
HIP 112077 |
11.09 |
| 2026-08-03 00:00 |
22:42:23.88 |
-33:25:36.7 |
HIP 112077 |
9.69 |
| 2026-08-03 12:00 |
22:42:17.73 |
-33:26:33.2 |
HIP 112077 |
8.35 |
| 2026-08-04 00:00 |
22:42:11.55 |
-33:27:29.4 |
HIP 112077 |
7.11 |
| 2026-08-04 12:00 |
22:42:05.33 |
-33:28:25.5 |
HIP 112077 |
6.05 |
| 2026-08-05 00:00 |
22:41:59.08 |
-33:29:21.4 |
HIP 112077 |
5.27 |
| 2026-08-05 12:00 |
22:41:52.81 |
-33:30:17.1 |
HIP 112077 |
4.91 |
| 2026-08-06 00:00 |
22:41:46.50 |
-33:31:12.6 |
HIP 112077 |
5.06 |
| 2026-08-06 12:00 |
22:41:40.16 |
-33:32:07.9 |
HIP 112077 |
5.70 |
| 2026-08-07 00:00 |
22:41:33.79 |
-33:33:03.0 |
HIP 112077 |
6.67 |
| 2026-08-07 12:00 |
22:41:27.40 |
-33:33:57.9 |
HIP 112077 |
7.87 |
| 2026-08-08 00:00 |
22:41:20.98 |
-33:34:52.5 |
HIP 112077 |
9.20 |
| 2026-08-08 12:00 |
22:41:14.52 |
-33:35:47.0 |
HIP 112077 |
10.61 |
| 2026-08-09 00:00 |
22:41:08.05 |
-33:36:41.2 |
HIP 112077 |
12.08 |
| 2026-08-09 12:00 |
22:41:01.54 |
-33:37:35.1 |
HIP 112077 |
13.59 |
| 2026-08-10 00:00 |
22:40:55.01 |
-33:38:28.9 |
HIP 112077 |
15.13 |
| 2026-08-10 12:00 |
22:40:48.45 |
-33:39:22.4 |
HIP 112077 |
16.69 |
| 2026-08-11 00:00 |
22:40:41.87 |
-33:40:15.6 |
HIP 112077 |
18.27 |
| 2026-08-11 12:00 |
22:40:35.27 |
-33:41:08.6 |
HIP 112077 |
19.85 |
| 2026-08-12 00:00 |
22:40:28.64 |
-33:42:01.4 |
HIP 112077 |
21.45 |
| 2026-08-12 12:00 |
22:40:21.99 |
-33:42:53.8 |
HIP 112077 |
23.05 |
| 2026-08-13 00:00 |
22:40:15.31 |
-33:43:46.1 |
HIP 112077 |
24.66 |
| 2026-08-13 12:00 |
22:40:08.61 |
-33:44:38.0 |
HIP 112077 |
26.28 |
| 2026-08-14 00:00 |
22:40:01.90 |
-33:45:29.7 |
HIP 112077 |
27.90 |
| 2026-08-14 12:00 |
22:39:55.16 |
-33:46:21.1 |
HIP 112046 |
29.37 |
| 2026-08-15 00:00 |
22:39:48.40 |
-33:47:12.2 |
HIP 111733 |
29.15 |
| 2026-08-15 12:00 |
22:39:41.62 |
-33:48:03.0 |
HIP 111733 |
28.67 |
| 2026-08-16 00:00 |
22:39:34.82 |
-33:48:53.6 |
HIP 111733 |
28.28 |
| 2026-08-16 12:00 |
22:39:28.01 |
-33:49:43.8 |
HIP 111733 |
27.97 |
| 2026-08-17 00:00 |
22:39:21.17 |
-33:50:33.8 |
HIP 111733 |
27.75 |
| 2026-08-17 12:00 |
22:39:14.32 |
-33:51:23.5 |
HIP 111733 |
27.62 |
| 2026-08-18 00:00 |
22:39:07.46 |
-33:52:12.8 |
HIP 111733 |
27.58 |
| 2026-08-18 12:00 |
22:39:00.58 |
-33:53:01.9 |
HIP 111744 |
26.49 |
| 2026-08-19 00:00 |
22:38:53.68 |
-33:53:50.6 |
HIP 111744 |
25.19 |