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
$$
M_a = (5.606 + 4.567\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
5.606 |
| n |
4.567 |
| gf |
0.823 |
| gb |
-1.000 |
| k |
1.000 |
| δ90 |
6.217 |
| 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 |
10:29:27.86 |
+29:16:41.0 |
HIP 51358 |
24.26 |
| 2026-07-29 12:00 |
10:29:31.12 |
+29:16:13.4 |
HIP 51358 |
24.75 |
| 2026-07-30 00:00 |
10:29:34.39 |
+29:15:45.9 |
HIP 51358 |
25.26 |
| 2026-07-30 12:00 |
10:29:37.68 |
+29:15:18.4 |
HIP 51358 |
25.78 |
| 2026-07-31 00:00 |
10:29:41.00 |
+29:14:51.0 |
HIP 51358 |
26.32 |
| 2026-07-31 12:00 |
10:29:44.32 |
+29:14:23.7 |
HIP 51358 |
26.88 |
| 2026-08-01 00:00 |
10:29:47.67 |
+29:13:56.5 |
HIP 51358 |
27.45 |
| 2026-08-01 12:00 |
10:29:51.03 |
+29:13:29.3 |
HIP 51358 |
28.03 |
| 2026-08-02 00:00 |
10:29:54.41 |
+29:13:02.3 |
HIP 51358 |
28.63 |
| 2026-08-02 12:00 |
10:29:57.80 |
+29:12:35.3 |
HIP 51367 |
28.58 |
| 2026-08-03 00:00 |
10:30:01.21 |
+29:12:08.4 |
HIP 51367 |
28.31 |
| 2026-08-03 12:00 |
10:30:04.63 |
+29:11:41.6 |
HIP 51367 |
28.07 |
| 2026-08-04 00:00 |
10:30:08.07 |
+29:11:14.9 |
HIP 51367 |
27.85 |
| 2026-08-04 12:00 |
10:30:11.53 |
+29:10:48.3 |
HIP 51367 |
27.67 |
| 2026-08-05 00:00 |
10:30:15.00 |
+29:10:21.8 |
HIP 51367 |
27.51 |
| 2026-08-05 12:00 |
10:30:18.48 |
+29:09:55.4 |
HIP 51367 |
27.38 |
| 2026-08-06 00:00 |
10:30:21.98 |
+29:09:29.1 |
HIP 51367 |
27.29 |
| 2026-08-06 12:00 |
10:30:25.49 |
+29:09:02.9 |
HIP 51367 |
27.22 |
| 2026-08-07 00:00 |
10:30:29.02 |
+29:08:36.8 |
HIP 51367 |
27.19 |
| 2026-08-07 12:00 |
10:30:32.56 |
+29:08:10.8 |
HIP 51367 |
27.19 |
| 2026-08-08 00:00 |
10:30:36.11 |
+29:07:44.9 |
HIP 51367 |
27.22 |
| 2026-08-08 12:00 |
10:30:39.68 |
+29:07:19.1 |
HIP 51367 |
27.29 |
| 2026-08-09 00:00 |
10:30:43.25 |
+29:06:53.4 |
HIP 51367 |
27.38 |
| 2026-08-09 12:00 |
10:30:46.84 |
+29:06:27.8 |
HIP 51367 |
27.51 |
| 2026-08-10 00:00 |
10:30:50.45 |
+29:06:02.4 |
HIP 51367 |
27.67 |
| 2026-08-10 12:00 |
10:30:54.06 |
+29:05:37.0 |
HIP 51367 |
27.86 |
| 2026-08-11 00:00 |
10:30:57.69 |
+29:05:11.8 |
HIP 51367 |
28.08 |
| 2026-08-11 12:00 |
10:31:01.32 |
+29:04:46.7 |
HIP 51367 |
28.33 |
| 2026-08-12 00:00 |
10:31:04.97 |
+29:04:21.7 |
HIP 51367 |
28.61 |
| 2026-08-12 12:00 |
10:31:08.63 |
+29:03:56.9 |
HIP 51367 |
28.92 |
| 2026-08-13 00:00 |
10:31:12.29 |
+29:03:32.1 |
HIP 51367 |
29.25 |
| 2026-08-13 12:00 |
10:31:15.97 |
+29:03:07.5 |
HIP 51367 |
29.61 |
| 2026-08-14 00:00 |
10:31:19.66 |
+29:02:43.1 |
HIP 51367 |
30.00 |
| 2026-08-14 12:00 |
10:31:23.35 |
+29:02:18.7 |
HIP 51684 |
29.58 |
| 2026-08-15 00:00 |
10:31:27.06 |
+29:01:54.5 |
HIP 51684 |
28.68 |
| 2026-08-15 12:00 |
10:31:30.77 |
+29:01:30.5 |
HIP 51684 |
27.79 |
| 2026-08-16 00:00 |
10:31:34.49 |
+29:01:06.6 |
HIP 51684 |
26.89 |
| 2026-08-16 12:00 |
10:31:38.22 |
+29:00:42.8 |
HIP 51684 |
25.99 |
| 2026-08-17 00:00 |
10:31:41.96 |
+29:00:19.1 |
HIP 51684 |
25.09 |
| 2026-08-17 12:00 |
10:31:45.70 |
+28:59:55.6 |
HIP 51684 |
24.19 |
| 2026-08-18 00:00 |
10:31:49.45 |
+28:59:32.3 |
HIP 51684 |
23.29 |
| 2026-08-18 12:00 |
10:31:53.21 |
+28:59:09.1 |
HIP 51684 |
22.39 |
| 2026-08-19 00:00 |
10:31:56.98 |
+28:58:46.0 |
HIP 51684 |
21.49 |