メタデータ
| 項目 |
値 |
| Designation |
C/2016 C2 (NEOWISE) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2016-04-19T14:19:31.131840Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:23Z |
| Obs used |
148 |
| NEO |
- |
| M1 |
13.800 |
| K1 |
20.750 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2016-03-12.0000000 |
| e |
0.97563583 |
| q (au) |
1.559754 |
| a (au) |
64.018322 |
| i (deg) |
38.156610 |
| Ω (om, deg) |
24.404634 |
| ω (w, deg) |
214.403353 |
| M (ma, deg) |
359.925732 |
等級
散乱 + 全体線形
$$
M_a = (14.251 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
14.251 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.500 |
| 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
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
01:42:17.26 |
+15:14:36.2 |
HIP 8073 |
24.07 |
| 2026-03-26 12:00 |
01:42:21.81 |
+15:15:02.8 |
HIP 8073 |
23.37 |
| 2026-03-27 00:00 |
01:42:26.37 |
+15:15:29.4 |
HIP 8073 |
22.70 |
| 2026-03-27 12:00 |
01:42:30.94 |
+15:15:56.2 |
HIP 8073 |
22.08 |
| 2026-03-28 00:00 |
01:42:35.52 |
+15:16:23.0 |
HIP 8073 |
21.50 |
| 2026-03-28 12:00 |
01:42:40.12 |
+15:16:50.0 |
HIP 8073 |
20.97 |
| 2026-03-29 00:00 |
01:42:44.72 |
+15:17:17.1 |
HIP 8073 |
20.51 |
| 2026-03-29 12:00 |
01:42:49.34 |
+15:17:44.2 |
HIP 8073 |
20.10 |
| 2026-03-30 00:00 |
01:42:53.97 |
+15:18:11.5 |
HIP 8073 |
19.75 |
| 2026-03-30 12:00 |
01:42:58.61 |
+15:18:38.9 |
HIP 8073 |
19.48 |
| 2026-03-31 00:00 |
01:43:03.27 |
+15:19:06.4 |
HIP 8073 |
19.27 |
| 2026-03-31 12:00 |
01:43:07.93 |
+15:19:34.0 |
HIP 8073 |
19.14 |
| 2026-04-01 00:00 |
01:43:12.60 |
+15:20:01.6 |
HIP 8073 |
19.09 |
| 2026-04-01 12:00 |
01:43:17.29 |
+15:20:29.4 |
HIP 8073 |
19.12 |
| 2026-04-02 00:00 |
01:43:21.98 |
+15:20:57.3 |
HIP 8073 |
19.23 |
| 2026-04-02 12:00 |
01:43:26.68 |
+15:21:25.2 |
HIP 8073 |
19.41 |
| 2026-04-03 00:00 |
01:43:31.40 |
+15:21:53.3 |
HIP 8073 |
19.67 |
| 2026-04-03 12:00 |
01:43:36.12 |
+15:22:21.4 |
HIP 8073 |
20.00 |
| 2026-04-04 00:00 |
01:43:40.85 |
+15:22:49.6 |
HIP 8073 |
20.41 |
| 2026-04-04 12:00 |
01:43:45.58 |
+15:23:18.0 |
HIP 8073 |
20.88 |
| 2026-04-05 00:00 |
01:43:50.33 |
+15:23:46.4 |
HIP 8073 |
21.41 |
| 2026-04-05 12:00 |
01:43:55.08 |
+15:24:14.8 |
HIP 8073 |
22.00 |
| 2026-04-06 00:00 |
01:43:59.85 |
+15:24:43.4 |
HIP 8073 |
22.65 |
| 2026-04-06 12:00 |
01:44:04.61 |
+15:25:12.0 |
HIP 8073 |
23.35 |
| 2026-04-07 00:00 |
01:44:09.39 |
+15:25:40.8 |
HIP 8073 |
24.09 |
| 2026-04-07 12:00 |
01:44:14.17 |
+15:26:09.6 |
HIP 8073 |
24.87 |
| 2026-04-08 00:00 |
01:44:18.96 |
+15:26:38.4 |
HIP 8073 |
25.69 |
| 2026-04-08 12:00 |
01:44:23.76 |
+15:27:07.4 |
HIP 8073 |
26.55 |
| 2026-04-09 00:00 |
01:44:28.56 |
+15:27:36.4 |
HIP 8073 |
27.44 |
| 2026-04-09 12:00 |
01:44:33.36 |
+15:28:05.5 |
HIP 8073 |
28.36 |
| 2026-04-10 00:00 |
01:44:38.17 |
+15:28:34.7 |
HIP 8073 |
29.31 |
| 2026-04-10 12:00 |
01:44:42.99 |
+15:29:03.9 |
HIP 8262 |
28.26 |
| 2026-04-11 00:00 |
01:44:47.81 |
+15:29:33.2 |
HIP 8262 |
27.01 |
| 2026-04-11 12:00 |
01:44:52.64 |
+15:30:02.5 |
HIP 8262 |
25.76 |
| 2026-04-12 00:00 |
01:44:57.47 |
+15:30:32.0 |
HIP 8262 |
24.50 |
| 2026-04-12 12:00 |
01:45:02.30 |
+15:31:01.4 |
HIP 8262 |
23.25 |
| 2026-04-13 00:00 |
01:45:07.13 |
+15:31:31.0 |
HIP 8262 |
22.00 |
| 2026-04-13 12:00 |
01:45:11.97 |
+15:32:00.6 |
HIP 8262 |
20.74 |
| 2026-04-14 00:00 |
01:45:16.82 |
+15:32:30.2 |
HIP 8262 |
19.49 |
| 2026-04-14 12:00 |
01:45:21.66 |
+15:33:00.0 |
HIP 8262 |
18.24 |
| 2026-04-15 00:00 |
01:45:26.51 |
+15:33:29.7 |
HIP 8262 |
16.99 |
| 2026-04-15 12:00 |
01:45:31.36 |
+15:33:59.5 |
HIP 8262 |
15.74 |
| 2026-04-16 00:00 |
01:45:36.21 |
+15:34:29.4 |
HIP 8262 |
14.50 |