メタデータ
| 項目 |
値 |
| Designation |
C/1987 W2 (Furuyama) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1988-03-03T01:38:49.009920Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:36Z |
| Obs used |
152 |
| NEO |
- |
| M1 |
9.400 |
| K1 |
4.500 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
1988-01-12.0000000 |
| e |
1.00023007 |
| q (au) |
1.679522 |
| a (au) |
-7299.904944 |
| i (deg) |
117.781967 |
| Ω (om, deg) |
250.752559 |
| ω (w, deg) |
233.626815 |
| M (ma, deg) |
-0.000081 |
等級
散乱 + 全体線形
$$
M_a = (4.822 + 5.790\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
4.822 |
| n |
5.790 |
| gf |
0.999 |
| gb |
-0.950 |
| k |
1.000 |
| δ90 |
9.999 |
| 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) |
| 2026-06-01 00:00 |
15:51:17.20 |
+11:20:02.3 |
HIP 77597 |
14.10 |
| 2026-06-01 12:00 |
15:51:15.31 |
+11:20:05.5 |
HIP 77597 |
13.71 |
| 2026-06-02 00:00 |
15:51:13.43 |
+11:20:08.7 |
HIP 77597 |
13.32 |
| 2026-06-02 12:00 |
15:51:11.56 |
+11:20:11.7 |
HIP 77597 |
12.94 |
| 2026-06-03 00:00 |
15:51:09.68 |
+11:20:14.6 |
HIP 77597 |
12.57 |
| 2026-06-03 12:00 |
15:51:07.81 |
+11:20:17.3 |
HIP 77597 |
12.20 |
| 2026-06-04 00:00 |
15:51:05.95 |
+11:20:19.9 |
HIP 77597 |
11.85 |
| 2026-06-04 12:00 |
15:51:04.08 |
+11:20:22.4 |
HIP 77597 |
11.50 |
| 2026-06-05 00:00 |
15:51:02.22 |
+11:20:24.8 |
HIP 77597 |
11.16 |
| 2026-06-05 12:00 |
15:51:00.37 |
+11:20:27.0 |
HIP 77597 |
10.84 |
| 2026-06-06 00:00 |
15:50:58.52 |
+11:20:29.0 |
HIP 77597 |
10.53 |
| 2026-06-06 12:00 |
15:50:56.67 |
+11:20:31.0 |
HIP 77597 |
10.23 |
| 2026-06-07 00:00 |
15:50:54.83 |
+11:20:32.8 |
HIP 77597 |
9.94 |
| 2026-06-07 12:00 |
15:50:52.99 |
+11:20:34.5 |
HIP 77597 |
9.67 |
| 2026-06-08 00:00 |
15:50:51.16 |
+11:20:36.0 |
HIP 77597 |
9.42 |
| 2026-06-08 12:00 |
15:50:49.34 |
+11:20:37.4 |
HIP 77597 |
9.18 |
| 2026-06-09 00:00 |
15:50:47.51 |
+11:20:38.7 |
HIP 77597 |
8.97 |
| 2026-06-09 12:00 |
15:50:45.70 |
+11:20:39.8 |
HIP 77597 |
8.77 |
| 2026-06-10 00:00 |
15:50:43.88 |
+11:20:40.8 |
HIP 77597 |
8.59 |
| 2026-06-10 12:00 |
15:50:42.08 |
+11:20:41.7 |
HIP 77597 |
8.44 |
| 2026-06-11 00:00 |
15:50:40.28 |
+11:20:42.5 |
HIP 77597 |
8.31 |
| 2026-06-11 12:00 |
15:50:38.48 |
+11:20:43.1 |
HIP 77597 |
8.20 |
| 2026-06-12 00:00 |
15:50:36.69 |
+11:20:43.5 |
HIP 77597 |
8.12 |
| 2026-06-12 12:00 |
15:50:34.91 |
+11:20:43.9 |
HIP 77597 |
8.07 |
| 2026-06-13 00:00 |
15:50:33.13 |
+11:20:44.1 |
HIP 77597 |
8.04 |
| 2026-06-13 12:00 |
15:50:31.36 |
+11:20:44.1 |
HIP 77597 |
8.03 |
| 2026-06-14 00:00 |
15:50:29.59 |
+11:20:44.1 |
HIP 77597 |
8.06 |
| 2026-06-14 12:00 |
15:50:27.83 |
+11:20:43.9 |
HIP 77597 |
8.10 |
| 2026-06-15 00:00 |
15:50:26.08 |
+11:20:43.5 |
HIP 77597 |
8.17 |
| 2026-06-15 12:00 |
15:50:24.34 |
+11:20:43.0 |
HIP 77597 |
8.27 |
| 2026-06-16 00:00 |
15:50:22.60 |
+11:20:42.4 |
HIP 77597 |
8.38 |
| 2026-06-16 12:00 |
15:50:20.87 |
+11:20:41.7 |
HIP 77597 |
8.52 |
| 2026-06-17 00:00 |
15:50:19.14 |
+11:20:40.8 |
HIP 77597 |
8.68 |
| 2026-06-17 12:00 |
15:50:17.43 |
+11:20:39.8 |
HIP 77597 |
8.86 |
| 2026-06-18 00:00 |
15:50:15.72 |
+11:20:38.7 |
HIP 77597 |
9.05 |
| 2026-06-18 12:00 |
15:50:14.02 |
+11:20:37.4 |
HIP 77597 |
9.26 |
| 2026-06-19 00:00 |
15:50:12.32 |
+11:20:36.0 |
HIP 77597 |
9.49 |
| 2026-06-19 12:00 |
15:50:10.64 |
+11:20:34.5 |
HIP 77597 |
9.72 |
| 2026-06-20 00:00 |
15:50:08.96 |
+11:20:32.8 |
HIP 77597 |
9.97 |
| 2026-06-20 12:00 |
15:50:07.29 |
+11:20:31.0 |
HIP 77597 |
10.24 |
| 2026-06-21 00:00 |
15:50:05.62 |
+11:20:29.1 |
HIP 77597 |
10.51 |
| 2026-06-21 12:00 |
15:50:03.97 |
+11:20:27.0 |
HIP 77597 |
10.79 |
| 2026-06-22 00:00 |
15:50:02.33 |
+11:20:24.8 |
HIP 77597 |
11.08 |