メタデータ
| 項目 |
値 |
| Designation |
C/2015 K7 (COIAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2013-02-19T19:51:17.665920Z |
| Orbit solution date (soln_date, UTC) |
2024-12-23T14:42:02Z |
| Obs used |
59 |
| NEO |
- |
| M1 |
7.400 |
| K1 |
10.250 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2015-05-17T09:45:54.432000Z |
| Discovery magnitude (MPC) |
23.40 g |
| Discovery observatory (MPC) |
T09 · Subaru Telescope, Maunakea |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2014-08-27.0000000 |
| e |
1.00398018 |
| q (au) |
9.940926 |
| a (au) |
-2497.604954 |
| i (deg) |
159.939165 |
| Ω (om, deg) |
258.001127 |
| ω (w, deg) |
5.158803 |
| M (ma, deg) |
0.004368 |
等級
散乱 + 全体線形
$$
M_a = (5.609 + 4.567\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
5.609 |
| n |
4.567 |
| gf |
0.937 |
| gb |
-1.000 |
| k |
1.000 |
| δ90 |
5.810 |
| 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 |
10:27:09.94 |
+30:22:29.1 |
HIP 50997 |
27.68 |
| 2026-05-12 12:00 |
10:27:07.79 |
+30:22:14.3 |
HIP 50997 |
27.21 |
| 2026-05-13 00:00 |
10:27:05.68 |
+30:21:59.2 |
HIP 50997 |
26.76 |
| 2026-05-13 12:00 |
10:27:03.62 |
+30:21:44.0 |
HIP 50997 |
26.32 |
| 2026-05-14 00:00 |
10:27:01.60 |
+30:21:28.5 |
HIP 50997 |
25.89 |
| 2026-05-14 12:00 |
10:26:59.62 |
+30:21:12.7 |
HIP 50997 |
25.48 |
| 2026-05-15 00:00 |
10:26:57.69 |
+30:20:56.7 |
HIP 50997 |
25.07 |
| 2026-05-15 12:00 |
10:26:55.80 |
+30:20:40.5 |
HIP 50997 |
24.68 |
| 2026-05-16 00:00 |
10:26:53.95 |
+30:20:24.1 |
HIP 50997 |
24.31 |
| 2026-05-16 12:00 |
10:26:52.15 |
+30:20:07.4 |
HIP 50997 |
23.95 |
| 2026-05-17 00:00 |
10:26:50.40 |
+30:19:50.5 |
HIP 50997 |
23.60 |
| 2026-05-17 12:00 |
10:26:48.68 |
+30:19:33.4 |
HIP 50997 |
23.26 |
| 2026-05-18 00:00 |
10:26:47.02 |
+30:19:16.1 |
HIP 50997 |
22.94 |
| 2026-05-18 12:00 |
10:26:45.39 |
+30:18:58.5 |
HIP 50997 |
22.63 |
| 2026-05-19 00:00 |
10:26:43.81 |
+30:18:40.8 |
HIP 50997 |
22.34 |
| 2026-05-19 12:00 |
10:26:42.27 |
+30:18:22.8 |
HIP 50997 |
22.07 |
| 2026-05-20 00:00 |
10:26:40.78 |
+30:18:04.6 |
HIP 50997 |
21.81 |
| 2026-05-20 12:00 |
10:26:39.33 |
+30:17:46.2 |
HIP 50997 |
21.56 |
| 2026-05-21 00:00 |
10:26:37.92 |
+30:17:27.6 |
HIP 50997 |
21.34 |
| 2026-05-21 12:00 |
10:26:36.56 |
+30:17:08.8 |
HIP 50997 |
21.12 |
| 2026-05-22 00:00 |
10:26:35.24 |
+30:16:49.7 |
HIP 50997 |
20.93 |
| 2026-05-22 12:00 |
10:26:33.97 |
+30:16:30.5 |
HIP 50997 |
20.75 |
| 2026-05-23 00:00 |
10:26:32.73 |
+30:16:11.1 |
HIP 50997 |
20.59 |
| 2026-05-23 12:00 |
10:26:31.54 |
+30:15:51.5 |
HIP 50997 |
20.45 |
| 2026-05-24 00:00 |
10:26:30.40 |
+30:15:31.7 |
HIP 50997 |
20.32 |
| 2026-05-24 12:00 |
10:26:29.30 |
+30:15:11.7 |
HIP 50997 |
20.21 |
| 2026-05-25 00:00 |
10:26:28.24 |
+30:14:51.5 |
HIP 50997 |
20.12 |
| 2026-05-25 12:00 |
10:26:27.22 |
+30:14:31.1 |
HIP 50997 |
20.05 |
| 2026-05-26 00:00 |
10:26:26.25 |
+30:14:10.5 |
HIP 50997 |
19.99 |
| 2026-05-26 12:00 |
10:26:25.32 |
+30:13:49.8 |
HIP 50997 |
19.95 |
| 2026-05-27 00:00 |
10:26:24.43 |
+30:13:28.8 |
HIP 50997 |
19.93 |
| 2026-05-27 12:00 |
10:26:23.58 |
+30:13:07.7 |
HIP 50997 |
19.93 |
| 2026-05-28 00:00 |
10:26:22.78 |
+30:12:46.4 |
HIP 50997 |
19.94 |
| 2026-05-28 12:00 |
10:26:22.02 |
+30:12:24.9 |
HIP 50997 |
19.97 |
| 2026-05-29 00:00 |
10:26:21.31 |
+30:12:03.3 |
HIP 50997 |
20.02 |
| 2026-05-29 12:00 |
10:26:20.63 |
+30:11:41.5 |
HIP 50997 |
20.08 |
| 2026-05-30 00:00 |
10:26:20.00 |
+30:11:19.5 |
HIP 50997 |
20.17 |
| 2026-05-30 12:00 |
10:26:19.41 |
+30:10:57.3 |
HIP 50997 |
20.26 |
| 2026-05-31 00:00 |
10:26:18.86 |
+30:10:35.0 |
HIP 50997 |
20.38 |
| 2026-05-31 12:00 |
10:26:18.35 |
+30:10:12.5 |
HIP 50997 |
20.51 |
| 2026-06-01 00:00 |
10:26:17.89 |
+30:09:49.8 |
HIP 50997 |
20.65 |
| 2026-06-01 12:00 |
10:26:17.47 |
+30:09:27.0 |
HIP 50997 |
20.81 |
| 2026-06-02 00:00 |
10:26:17.08 |
+30:09:04.1 |
HIP 50997 |
20.99 |