メタデータ
| 項目 |
値 |
| Designation |
327P/Van Ness |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2022-09-02T13:33:36.086400Z |
| Orbit solution date (soln_date, UTC) |
2024-06-21T13:42:21Z |
| Obs used |
900 |
| NEO |
- |
| M1 |
14.800 |
| K1 |
11.500 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2020-09-26.0000000 |
| e |
0.56283038 |
| q (au) |
1.557541 |
| a (au) |
3.562783 |
| i (deg) |
36.245156 |
| Ω (om, deg) |
173.974419 |
| ω (w, deg) |
185.022025 |
| M (ma, deg) |
256.444765 |
等級
散乱 + 全体線形
$$
M_a = (14.825 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
14.825 |
| n |
6.000 |
| gf |
0.995 |
| gb |
-0.647 |
| k |
0.800 |
| δ90 |
2.043 |
| 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
残差 (区間線形)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| 開始日 (UTC) |
終了日 (UTC) |
a |
b |
| 2020-05-30 |
2022-09-02 |
-11.8557 |
+2.478 |
| 2022-09-03 |
2023-01-20 |
-0.5923 |
+0.111 |
log10 r = log10(太陽距離/AU)、Δ = 地球距離(AU)
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-06-01 00:00 |
11:47:37.48 |
+09:31:33.9 |
HIP 57501 |
7.42 |
| 2026-06-01 12:00 |
11:47:37.59 |
+09:31:50.1 |
HIP 57501 |
7.57 |
| 2026-06-02 00:00 |
11:47:37.86 |
+09:32:05.0 |
HIP 57501 |
7.75 |
| 2026-06-02 12:00 |
11:47:38.30 |
+09:32:18.7 |
HIP 57501 |
7.96 |
| 2026-06-03 00:00 |
11:47:38.90 |
+09:32:31.2 |
HIP 57501 |
8.19 |
| 2026-06-03 12:00 |
11:47:39.67 |
+09:32:42.5 |
HIP 57501 |
8.45 |
| 2026-06-04 00:00 |
11:47:40.61 |
+09:32:52.6 |
HIP 57501 |
8.74 |
| 2026-06-04 12:00 |
11:47:41.72 |
+09:33:01.5 |
HIP 57501 |
9.05 |
| 2026-06-05 00:00 |
11:47:42.99 |
+09:33:09.3 |
HIP 57501 |
9.38 |
| 2026-06-05 12:00 |
11:47:44.42 |
+09:33:15.8 |
HIP 57501 |
9.74 |
| 2026-06-06 00:00 |
11:47:46.02 |
+09:33:21.2 |
HIP 57501 |
10.13 |
| 2026-06-06 12:00 |
11:47:47.79 |
+09:33:25.4 |
HIP 57501 |
10.54 |
| 2026-06-07 00:00 |
11:47:49.71 |
+09:33:28.4 |
HIP 57501 |
10.98 |
| 2026-06-07 12:00 |
11:47:51.81 |
+09:33:30.3 |
HIP 57501 |
11.45 |
| 2026-06-08 00:00 |
11:47:54.06 |
+09:33:31.0 |
HIP 57501 |
11.95 |
| 2026-06-08 12:00 |
11:47:56.48 |
+09:33:30.6 |
HIP 57501 |
12.48 |
| 2026-06-09 00:00 |
11:47:59.06 |
+09:33:29.1 |
HIP 57501 |
13.05 |
| 2026-06-09 12:00 |
11:48:01.80 |
+09:33:26.4 |
HIP 57501 |
13.65 |
| 2026-06-10 00:00 |
11:48:04.71 |
+09:33:22.6 |
HIP 57501 |
14.29 |
| 2026-06-10 12:00 |
11:48:07.77 |
+09:33:17.6 |
HIP 57501 |
14.97 |
| 2026-06-11 00:00 |
11:48:11.00 |
+09:33:11.6 |
HIP 57501 |
15.69 |
| 2026-06-11 12:00 |
11:48:14.38 |
+09:33:04.4 |
HIP 57501 |
16.45 |
| 2026-06-12 00:00 |
11:48:17.93 |
+09:32:56.1 |
HIP 57501 |
17.25 |
| 2026-06-12 12:00 |
11:48:21.63 |
+09:32:46.8 |
HIP 57501 |
18.09 |
| 2026-06-13 00:00 |
11:48:25.50 |
+09:32:36.3 |
HIP 57501 |
18.97 |
| 2026-06-13 12:00 |
11:48:29.52 |
+09:32:24.7 |
HIP 57501 |
19.89 |
| 2026-06-14 00:00 |
11:48:33.70 |
+09:32:12.1 |
HIP 57501 |
20.86 |
| 2026-06-14 12:00 |
11:48:38.04 |
+09:31:58.4 |
HIP 57501 |
21.87 |
| 2026-06-15 00:00 |
11:48:42.54 |
+09:31:43.6 |
HIP 57501 |
22.93 |
| 2026-06-15 12:00 |
11:48:47.19 |
+09:31:27.8 |
HIP 57501 |
24.02 |
| 2026-06-16 00:00 |
11:48:52.00 |
+09:31:10.9 |
HIP 57501 |
25.16 |
| 2026-06-16 12:00 |
11:48:56.96 |
+09:30:53.0 |
HIP 57755 |
25.58 |
| 2026-06-17 00:00 |
11:49:02.08 |
+09:30:34.1 |
HIP 57755 |
24.32 |
| 2026-06-17 12:00 |
11:49:07.35 |
+09:30:14.1 |
HIP 57755 |
23.03 |
| 2026-06-18 00:00 |
11:49:12.77 |
+09:29:53.1 |
HIP 57755 |
21.70 |
| 2026-06-18 12:00 |
11:49:18.35 |
+09:29:31.1 |
HIP 57755 |
20.35 |
| 2026-06-19 00:00 |
11:49:24.08 |
+09:29:08.0 |
HIP 57755 |
18.98 |
| 2026-06-19 12:00 |
11:49:29.96 |
+09:28:44.0 |
HIP 57755 |
17.58 |
| 2026-06-20 00:00 |
11:49:35.99 |
+09:28:19.0 |
HIP 57755 |
16.17 |
| 2026-06-20 12:00 |
11:49:42.17 |
+09:27:53.0 |
HIP 57755 |
14.76 |
| 2026-06-21 00:00 |
11:49:48.49 |
+09:27:26.0 |
HIP 57755 |
13.35 |
| 2026-06-21 12:00 |
11:49:54.97 |
+09:26:58.1 |
HIP 57755 |
11.96 |
| 2026-06-22 00:00 |
11:50:01.59 |
+09:26:29.2 |
HIP 57755 |
10.63 |