メタデータ
| 項目 |
値 |
| Designation |
C/1998 K2 (LINEAR) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1998-09-01T05:31:38.231040Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:53Z |
| Obs used |
201 |
| NEO |
- |
| M1 |
10.300 |
| K1 |
5.500 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
1998-10-01.0000000 |
| e |
0.99927629 |
| q (au) |
2.323478 |
| a (au) |
3210.507001 |
| i (deg) |
64.456675 |
| Ω (om, deg) |
68.781077 |
| ω (w, deg) |
221.417912 |
| M (ma, deg) |
0.000161 |
等級
散乱 + 全体線形
$$
M_a = (11.927 + 2.178\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
11.927 |
| n |
2.178 |
| gf |
1.000 |
| gb |
-0.601 |
| 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) |
| 2026-05-12 00:00 |
04:49:12.84 |
+37:17:37.1 |
HIP 22421 |
4.21 |
| 2026-05-12 12:00 |
04:49:15.58 |
+37:17:38.8 |
HIP 22421 |
3.77 |
| 2026-05-13 00:00 |
04:49:18.34 |
+37:17:40.6 |
HIP 22421 |
3.35 |
| 2026-05-13 12:00 |
04:49:21.10 |
+37:17:42.5 |
HIP 22421 |
2.97 |
| 2026-05-14 00:00 |
04:49:23.87 |
+37:17:44.5 |
HIP 22421 |
2.65 |
| 2026-05-14 12:00 |
04:49:26.65 |
+37:17:46.6 |
HIP 22421 |
2.42 |
| 2026-05-15 00:00 |
04:49:29.43 |
+37:17:48.7 |
HIP 22421 |
2.29 |
| 2026-05-15 12:00 |
04:49:32.23 |
+37:17:50.9 |
HIP 22421 |
2.30 |
| 2026-05-16 00:00 |
04:49:35.03 |
+37:17:53.2 |
HIP 22421 |
2.43 |
| 2026-05-16 12:00 |
04:49:37.84 |
+37:17:55.6 |
HIP 22421 |
2.68 |
| 2026-05-17 00:00 |
04:49:40.66 |
+37:17:58.1 |
HIP 22421 |
3.01 |
| 2026-05-17 12:00 |
04:49:43.48 |
+37:18:00.6 |
HIP 22421 |
3.41 |
| 2026-05-18 00:00 |
04:49:46.31 |
+37:18:03.2 |
HIP 22421 |
3.84 |
| 2026-05-18 12:00 |
04:49:49.15 |
+37:18:05.9 |
HIP 22421 |
4.31 |
| 2026-05-19 00:00 |
04:49:52.00 |
+37:18:08.7 |
HIP 22421 |
4.80 |
| 2026-05-19 12:00 |
04:49:54.85 |
+37:18:11.6 |
HIP 22421 |
5.30 |
| 2026-05-20 00:00 |
04:49:57.71 |
+37:18:14.5 |
HIP 22421 |
5.82 |
| 2026-05-20 12:00 |
04:50:00.57 |
+37:18:17.5 |
HIP 22421 |
6.35 |
| 2026-05-21 00:00 |
04:50:03.44 |
+37:18:20.6 |
HIP 22421 |
6.88 |
| 2026-05-21 12:00 |
04:50:06.32 |
+37:18:23.8 |
HIP 22421 |
7.43 |
| 2026-05-22 00:00 |
04:50:09.20 |
+37:18:27.0 |
HIP 22421 |
7.97 |
| 2026-05-22 12:00 |
04:50:12.09 |
+37:18:30.3 |
HIP 22421 |
8.53 |
| 2026-05-23 00:00 |
04:50:14.98 |
+37:18:33.7 |
HIP 22421 |
9.08 |
| 2026-05-23 12:00 |
04:50:17.87 |
+37:18:37.2 |
HIP 22421 |
9.64 |
| 2026-05-24 00:00 |
04:50:20.78 |
+37:18:40.8 |
HIP 22421 |
10.20 |
| 2026-05-24 12:00 |
04:50:23.68 |
+37:18:44.4 |
HIP 22421 |
10.77 |
| 2026-05-25 00:00 |
04:50:26.59 |
+37:18:48.1 |
HIP 22421 |
11.33 |
| 2026-05-25 12:00 |
04:50:29.50 |
+37:18:51.9 |
HIP 22421 |
11.90 |
| 2026-05-26 00:00 |
04:50:32.42 |
+37:18:55.7 |
HIP 22421 |
12.47 |
| 2026-05-26 12:00 |
04:50:35.34 |
+37:18:59.7 |
HIP 22421 |
13.04 |
| 2026-05-27 00:00 |
04:50:38.27 |
+37:19:03.7 |
HIP 22453 |
13.40 |
| 2026-05-27 12:00 |
04:50:41.20 |
+37:19:07.8 |
HIP 22453 |
13.73 |
| 2026-05-28 00:00 |
04:50:44.13 |
+37:19:11.9 |
HIP 22453 |
14.08 |
| 2026-05-28 12:00 |
04:50:47.06 |
+37:19:16.2 |
HIP 22453 |
14.45 |
| 2026-05-29 00:00 |
04:50:50.00 |
+37:19:20.5 |
HIP 22453 |
14.82 |
| 2026-05-29 12:00 |
04:50:52.94 |
+37:19:24.9 |
HIP 22453 |
15.21 |
| 2026-05-30 00:00 |
04:50:55.88 |
+37:19:29.3 |
HIP 22453 |
15.62 |
| 2026-05-30 12:00 |
04:50:58.82 |
+37:19:33.9 |
HIP 22453 |
16.03 |
| 2026-05-31 00:00 |
04:51:01.77 |
+37:19:38.5 |
HIP 22453 |
16.45 |
| 2026-05-31 12:00 |
04:51:04.72 |
+37:19:43.1 |
HIP 22453 |
16.89 |
| 2026-06-01 00:00 |
04:51:07.67 |
+37:19:47.9 |
HIP 22453 |
17.33 |
| 2026-06-01 12:00 |
04:51:10.62 |
+37:19:52.7 |
HIP 22453 |
17.78 |
| 2026-06-02 00:00 |
04:51:13.57 |
+37:19:57.6 |
HIP 22453 |
18.24 |