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) |
| 2026-09-20 00:00 |
22:31:28.25 |
-34:32:47.5 |
HIP 111299 |
31.14 |
| 2026-09-20 12:00 |
22:31:21.67 |
-34:33:10.1 |
HIP 111299 |
31.56 |
| 2026-09-21 00:00 |
22:31:15.12 |
-34:33:32.2 |
HIP 111299 |
32.05 |
| 2026-09-21 12:00 |
22:31:08.59 |
-34:33:53.8 |
HIP 111299 |
32.58 |
| 2026-09-22 00:00 |
22:31:02.09 |
-34:34:15.0 |
HIP 111299 |
33.17 |
| 2026-09-22 12:00 |
22:30:55.62 |
-34:34:35.8 |
HIP 111256 |
33.62 |
| 2026-09-23 00:00 |
22:30:49.17 |
-34:34:56.0 |
HIP 111256 |
34.08 |
| 2026-09-23 12:00 |
22:30:42.75 |
-34:35:15.8 |
HIP 111256 |
34.59 |
| 2026-09-24 00:00 |
22:30:36.36 |
-34:35:35.1 |
HIP 111256 |
35.14 |
| 2026-09-24 12:00 |
22:30:30.00 |
-34:35:54.0 |
HIP 111256 |
35.74 |
| 2026-09-25 00:00 |
22:30:23.67 |
-34:36:12.4 |
HIP 111256 |
36.38 |
| 2026-09-25 12:00 |
22:30:17.37 |
-34:36:30.3 |
HIP 111256 |
37.06 |
| 2026-09-26 00:00 |
22:30:11.10 |
-34:36:47.8 |
HIP 111256 |
37.78 |
| 2026-09-26 12:00 |
22:30:04.86 |
-34:37:04.8 |
HIP 111256 |
38.52 |
| 2026-09-27 00:00 |
22:29:58.65 |
-34:37:21.3 |
HIP 110837 |
38.13 |
| 2026-09-27 12:00 |
22:29:52.47 |
-34:37:37.4 |
HIP 110837 |
37.17 |
| 2026-09-28 00:00 |
22:29:46.33 |
-34:37:52.9 |
HIP 110837 |
36.23 |
| 2026-09-28 12:00 |
22:29:40.22 |
-34:38:08.1 |
HIP 110837 |
35.32 |
| 2026-09-29 00:00 |
22:29:34.15 |
-34:38:22.7 |
HIP 110837 |
34.44 |
| 2026-09-29 12:00 |
22:29:28.10 |
-34:38:36.9 |
HIP 110837 |
33.58 |
| 2026-09-30 00:00 |
22:29:22.10 |
-34:38:50.6 |
HIP 110837 |
32.75 |
| 2026-09-30 12:00 |
22:29:16.12 |
-34:39:03.9 |
HIP 110837 |
31.94 |
| 2026-10-01 00:00 |
22:29:10.19 |
-34:39:16.7 |
HIP 110837 |
31.17 |
| 2026-10-01 12:00 |
22:29:04.29 |
-34:39:29.0 |
HIP 110837 |
30.42 |
| 2026-10-02 00:00 |
22:28:58.42 |
-34:39:40.8 |
HIP 110837 |
29.71 |
| 2026-10-02 12:00 |
22:28:52.60 |
-34:39:52.2 |
HIP 110837 |
29.04 |
| 2026-10-03 00:00 |
22:28:46.81 |
-34:40:03.1 |
HIP 110837 |
28.39 |
| 2026-10-03 12:00 |
22:28:41.06 |
-34:40:13.6 |
HIP 110837 |
27.79 |
| 2026-10-04 00:00 |
22:28:35.35 |
-34:40:23.5 |
HIP 110837 |
27.22 |
| 2026-10-04 12:00 |
22:28:29.68 |
-34:40:33.1 |
HIP 110837 |
26.69 |
| 2026-10-05 00:00 |
22:28:24.04 |
-34:40:42.1 |
HIP 110837 |
26.20 |
| 2026-10-05 12:00 |
22:28:18.45 |
-34:40:50.7 |
HIP 110837 |
25.75 |
| 2026-10-06 00:00 |
22:28:12.90 |
-34:40:58.8 |
HIP 110837 |
25.34 |
| 2026-10-06 12:00 |
22:28:07.39 |
-34:41:06.4 |
HIP 110837 |
24.98 |
| 2026-10-07 00:00 |
22:28:01.92 |
-34:41:13.6 |
HIP 110837 |
24.66 |
| 2026-10-07 12:00 |
22:27:56.49 |
-34:41:20.3 |
HIP 110837 |
24.38 |
| 2026-10-08 00:00 |
22:27:51.11 |
-34:41:26.5 |
HIP 110837 |
24.15 |
| 2026-10-08 12:00 |
22:27:45.77 |
-34:41:32.3 |
HIP 110837 |
23.96 |
| 2026-10-09 00:00 |
22:27:40.47 |
-34:41:37.6 |
HIP 110837 |
23.82 |
| 2026-10-09 12:00 |
22:27:35.22 |
-34:41:42.4 |
HIP 110837 |
23.72 |
| 2026-10-10 00:00 |
22:27:30.01 |
-34:41:46.8 |
HIP 110837 |
23.66 |
| 2026-10-10 12:00 |
22:27:24.85 |
-34:41:50.7 |
HIP 110837 |
23.64 |
| 2026-10-11 00:00 |
22:27:19.73 |
-34:41:54.1 |
HIP 110837 |
23.66 |