メタデータ
| 項目 |
値 |
| Designation |
221P/LINEAR |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2009-01-24T08:32:46.219200Z |
| Orbit solution date (soln_date, UTC) |
2022-10-28T22:13:13Z |
| Obs used |
627 |
| NEO |
- |
| M1 |
14.000 |
| K1 |
13.250 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2011-08-08.0000000 |
| e |
0.48757555 |
| q (au) |
1.779766 |
| a (au) |
3.473226 |
| i (deg) |
11.431021 |
| Ω (om, deg) |
229.989314 |
| ω (w, deg) |
39.511181 |
| M (ma, deg) |
140.944591 |
等級
散乱 + 全体線形
$$
M_a = (12.562 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
12.562 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.891 |
| k |
0.999 |
| δ90 |
9.995 |
| 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 |
06:42:16.35 |
+12:50:28.4 |
HIP 31915 |
32.85 |
| 2026-03-26 12:00 |
06:42:21.72 |
+12:51:19.7 |
HIP 32249 |
32.63 |
| 2026-03-27 00:00 |
06:42:27.31 |
+12:52:10.6 |
HIP 32249 |
31.06 |
| 2026-03-27 12:00 |
06:42:33.11 |
+12:53:01.2 |
HIP 32249 |
29.46 |
| 2026-03-28 00:00 |
06:42:39.12 |
+12:53:51.4 |
HIP 32249 |
27.83 |
| 2026-03-28 12:00 |
06:42:45.35 |
+12:54:41.2 |
HIP 32249 |
26.18 |
| 2026-03-29 00:00 |
06:42:51.78 |
+12:55:30.6 |
HIP 32249 |
24.51 |
| 2026-03-29 12:00 |
06:42:58.43 |
+12:56:19.7 |
HIP 32249 |
22.83 |
| 2026-03-30 00:00 |
06:43:05.28 |
+12:57:08.4 |
HIP 32249 |
21.14 |
| 2026-03-30 12:00 |
06:43:12.34 |
+12:57:56.7 |
HIP 32249 |
19.46 |
| 2026-03-31 00:00 |
06:43:19.60 |
+12:58:44.6 |
HIP 32249 |
17.80 |
| 2026-03-31 12:00 |
06:43:27.08 |
+12:59:32.1 |
HIP 32249 |
16.18 |
| 2026-04-01 00:00 |
06:43:34.75 |
+13:00:19.2 |
HIP 32249 |
14.64 |
| 2026-04-01 12:00 |
06:43:42.63 |
+13:01:05.9 |
HIP 32249 |
13.23 |
| 2026-04-02 00:00 |
06:43:50.71 |
+13:01:52.2 |
HIP 32249 |
12.00 |
| 2026-04-02 12:00 |
06:43:59.00 |
+13:02:38.0 |
HIP 32249 |
11.05 |
| 2026-04-03 00:00 |
06:44:07.48 |
+13:03:23.5 |
HIP 32249 |
10.49 |
| 2026-04-03 12:00 |
06:44:16.16 |
+13:04:08.6 |
HIP 32249 |
10.39 |
| 2026-04-04 00:00 |
06:44:25.04 |
+13:04:53.2 |
HIP 32249 |
10.81 |
| 2026-04-04 12:00 |
06:44:34.12 |
+13:05:37.4 |
HIP 32249 |
11.70 |
| 2026-04-05 00:00 |
06:44:43.40 |
+13:06:21.2 |
HIP 32249 |
13.00 |
| 2026-04-05 12:00 |
06:44:52.87 |
+13:07:04.5 |
HIP 32359 |
14.11 |
| 2026-04-06 00:00 |
06:45:02.54 |
+13:07:47.4 |
HIP 32359 |
12.71 |
| 2026-04-06 12:00 |
06:45:12.40 |
+13:08:29.9 |
HIP 32359 |
11.67 |
| 2026-04-07 00:00 |
06:45:22.45 |
+13:09:11.9 |
HIP 32359 |
11.12 |
| 2026-04-07 12:00 |
06:45:32.70 |
+13:09:53.5 |
HIP 32359 |
11.17 |
| 2026-04-08 00:00 |
06:45:43.13 |
+13:10:34.6 |
HIP 32359 |
11.83 |
| 2026-04-08 12:00 |
06:45:53.76 |
+13:11:15.3 |
HIP 32359 |
13.04 |
| 2026-04-09 00:00 |
06:46:04.57 |
+13:11:55.5 |
HIP 32359 |
14.69 |
| 2026-04-09 12:00 |
06:46:15.58 |
+13:12:35.2 |
HIP 32359 |
16.66 |
| 2026-04-10 00:00 |
06:46:26.77 |
+13:13:14.5 |
HIP 32359 |
18.88 |
| 2026-04-10 12:00 |
06:46:38.15 |
+13:13:53.3 |
HIP 32359 |
21.28 |
| 2026-04-11 00:00 |
06:46:49.71 |
+13:14:31.6 |
HIP 32359 |
23.82 |
| 2026-04-11 12:00 |
06:47:01.46 |
+13:15:09.5 |
HIP 32359 |
26.48 |
| 2026-04-12 00:00 |
06:47:13.39 |
+13:15:46.8 |
HIP 32687 |
28.64 |
| 2026-04-12 12:00 |
06:47:25.50 |
+13:16:23.7 |
HIP 32687 |
25.63 |
| 2026-04-13 00:00 |
06:47:37.80 |
+13:17:00.1 |
HIP 32687 |
22.58 |
| 2026-04-13 12:00 |
06:47:50.27 |
+13:17:36.0 |
HIP 32687 |
19.49 |
| 2026-04-14 00:00 |
06:48:02.93 |
+13:18:11.4 |
HIP 32687 |
16.36 |
| 2026-04-14 12:00 |
06:48:15.76 |
+13:18:46.2 |
HIP 32687 |
13.19 |
| 2026-04-15 00:00 |
06:48:28.78 |
+13:19:20.6 |
HIP 32687 |
9.98 |
| 2026-04-15 12:00 |
06:48:41.97 |
+13:19:54.5 |
HIP 32687 |
6.76 |
| 2026-04-16 00:00 |
06:48:55.33 |
+13:20:27.9 |
HIP 32687 |
3.55 |