メタデータ
| 項目 |
値 |
| Designation |
213P/Van Ness |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2017-09-24T09:09:50.725440Z |
| Orbit solution date (soln_date, UTC) |
2025-04-11T15:15:55Z |
| Obs used |
367 |
| NEO |
- |
| M1 |
10.800 |
| K1 |
16.000 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2018-02-12.0000000 |
| e |
0.40755795 |
| q (au) |
1.983344 |
| a (au) |
3.347744 |
| i (deg) |
10.377842 |
| Ω (om, deg) |
311.315921 |
| ω (w, deg) |
5.559827 |
| M (ma, deg) |
22.626485 |
等級
散乱 + 全体線形
$$
M_a = (18.184 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
18.184 |
| n |
2.000 |
| gf |
0.996 |
| gb |
-0.598 |
| k |
0.800 |
| 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 |
08:38:14.24 |
+18:56:20.9 |
HIP 42284 |
13.88 |
| 2026-07-29 12:00 |
08:38:42.03 |
+18:54:16.3 |
HIP 42284 |
19.93 |
| 2026-07-30 00:00 |
08:39:09.81 |
+18:52:11.4 |
HIP 42487 |
20.57 |
| 2026-07-30 12:00 |
08:39:37.57 |
+18:50:06.3 |
HIP 42487 |
16.98 |
| 2026-07-31 00:00 |
08:40:05.32 |
+18:48:01.0 |
HIP 42487 |
15.76 |
| 2026-07-31 12:00 |
08:40:33.05 |
+18:45:55.4 |
HIP 42487 |
17.42 |
| 2026-08-01 00:00 |
08:41:00.77 |
+18:43:49.7 |
HIP 42705 |
20.60 |
| 2026-08-01 12:00 |
08:41:28.48 |
+18:41:43.7 |
HIP 42705 |
17.49 |
| 2026-08-02 00:00 |
08:41:56.16 |
+18:39:37.5 |
HIP 42705 |
16.80 |
| 2026-08-02 12:00 |
08:42:23.84 |
+18:37:31.1 |
HIP 42705 |
18.80 |
| 2026-08-03 00:00 |
08:42:51.49 |
+18:35:24.4 |
HIP 42705 |
22.79 |
| 2026-08-03 12:00 |
08:43:19.13 |
+18:33:17.6 |
HIP 42791 |
24.39 |
| 2026-08-04 00:00 |
08:43:46.74 |
+18:31:10.6 |
HIP 42791 |
23.94 |
| 2026-08-04 12:00 |
08:44:14.34 |
+18:29:03.3 |
HIP 42911 |
20.76 |
| 2026-08-05 00:00 |
08:44:41.92 |
+18:26:55.9 |
HIP 42911 |
17.64 |
| 2026-08-05 12:00 |
08:45:09.48 |
+18:24:48.2 |
HIP 42911 |
16.91 |
| 2026-08-06 00:00 |
08:45:37.02 |
+18:22:40.3 |
HIP 43044 |
14.47 |
| 2026-08-06 12:00 |
08:46:04.54 |
+18:20:32.3 |
HIP 43044 |
9.90 |
| 2026-08-07 00:00 |
08:46:32.04 |
+18:18:24.0 |
HIP 43044 |
9.01 |
| 2026-08-07 12:00 |
08:46:59.52 |
+18:16:15.6 |
HIP 43044 |
12.59 |
| 2026-08-08 00:00 |
08:47:26.97 |
+18:14:07.0 |
HIP 43044 |
18.17 |
| 2026-08-08 12:00 |
08:47:54.40 |
+18:11:58.1 |
HIP 43044 |
24.41 |
| 2026-08-09 00:00 |
08:48:21.80 |
+18:09:49.1 |
HIP 43044 |
30.91 |
| 2026-08-09 12:00 |
08:48:49.19 |
+18:07:40.0 |
HIP 43421 |
27.47 |
| 2026-08-10 00:00 |
08:49:16.54 |
+18:05:30.6 |
HIP 43421 |
20.63 |
| 2026-08-10 12:00 |
08:49:43.87 |
+18:03:21.1 |
HIP 43421 |
13.81 |
| 2026-08-11 00:00 |
08:50:11.17 |
+18:01:11.4 |
HIP 43421 |
7.02 |
| 2026-08-11 12:00 |
08:50:38.45 |
+17:59:01.5 |
HIP 43421 |
1.27 |
| 2026-08-12 00:00 |
08:51:05.69 |
+17:56:51.5 |
HIP 43421 |
6.88 |
| 2026-08-12 12:00 |
08:51:32.91 |
+17:54:41.3 |
HIP 43510 |
13.10 |
| 2026-08-13 00:00 |
08:52:00.10 |
+17:52:31.0 |
HIP 43510 |
15.45 |
| 2026-08-13 12:00 |
08:52:27.25 |
+17:50:20.5 |
HIP 43510 |
19.97 |
| 2026-08-14 00:00 |
08:52:54.38 |
+17:48:09.9 |
HIP 43672 |
20.48 |
| 2026-08-14 12:00 |
08:53:21.47 |
+17:45:59.1 |
HIP 43672 |
15.00 |
| 2026-08-15 00:00 |
08:53:48.53 |
+17:43:48.2 |
HIP 43672 |
11.11 |
| 2026-08-15 12:00 |
08:54:15.56 |
+17:41:37.1 |
HIP 43672 |
10.69 |
| 2026-08-16 00:00 |
08:54:42.56 |
+17:39:25.9 |
HIP 43672 |
14.06 |
| 2026-08-16 12:00 |
08:55:09.51 |
+17:37:14.6 |
HIP 43846 |
10.15 |
| 2026-08-17 00:00 |
08:55:36.44 |
+17:35:03.1 |
HIP 43846 |
5.91 |
| 2026-08-17 12:00 |
08:56:03.33 |
+17:32:51.6 |
HIP 43846 |
7.66 |
| 2026-08-18 00:00 |
08:56:30.18 |
+17:30:39.9 |
HIP 43915 |
4.16 |
| 2026-08-18 12:00 |
08:56:56.99 |
+17:28:28.0 |
HIP 43915 |
2.66 |
| 2026-08-19 00:00 |
08:57:23.77 |
+17:26:16.1 |
HIP 43915 |
9.39 |