メタデータ
| 項目 |
値 |
| Designation |
C/2018 F3 (Johnson) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2017-08-15T05:34:33.502080Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:43Z |
| Obs used |
51 |
| NEO |
- |
| M1 |
12.900 |
| K1 |
10.000 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2018-03-20T06:23:56.832000Z |
| Discovery magnitude (MPC) |
19.40 G |
| Discovery observatory (MPC) |
G96 · Mt. Lemmon Survey |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2018-03-23.0000000 |
| e |
1.00001624 |
| q (au) |
2.483147 |
| a (au) |
-152892.693615 |
| i (deg) |
105.534913 |
| Ω (om, deg) |
173.031139 |
| ω (w, deg) |
293.010797 |
| M (ma, deg) |
0.000004 |
等級
散乱 + 全体線形
$$
M_a = (14.744 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
14.744 |
| n |
2.000 |
| gf |
0.993 |
| gb |
-1.000 |
| k |
1.000 |
| 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 |
13:07:42.20 |
+76:33:40.8 |
HIP 64452 |
24.13 |
| 2026-05-12 12:00 |
13:07:25.21 |
+76:33:07.7 |
HIP 64452 |
24.50 |
| 2026-05-13 00:00 |
13:07:08.35 |
+76:32:33.8 |
HIP 64452 |
24.90 |
| 2026-05-13 12:00 |
13:06:51.63 |
+76:31:59.4 |
HIP 64452 |
25.34 |
| 2026-05-14 00:00 |
13:06:35.04 |
+76:31:24.3 |
HIP 64452 |
25.81 |
| 2026-05-14 12:00 |
13:06:18.58 |
+76:30:48.5 |
HIP 64452 |
26.31 |
| 2026-05-15 00:00 |
13:06:02.26 |
+76:30:12.2 |
HIP 64452 |
26.83 |
| 2026-05-15 12:00 |
13:05:46.08 |
+76:29:35.2 |
HIP 64452 |
27.39 |
| 2026-05-16 00:00 |
13:05:30.04 |
+76:28:57.6 |
HIP 64452 |
27.96 |
| 2026-05-16 12:00 |
13:05:14.15 |
+76:28:19.4 |
HIP 64452 |
28.57 |
| 2026-05-17 00:00 |
13:04:58.40 |
+76:27:40.6 |
HIP 64452 |
29.19 |
| 2026-05-17 12:00 |
13:04:42.79 |
+76:27:01.2 |
HIP 63200 |
28.62 |
| 2026-05-18 00:00 |
13:04:27.33 |
+76:26:21.2 |
HIP 63200 |
27.58 |
| 2026-05-18 12:00 |
13:04:12.01 |
+76:25:40.6 |
HIP 63200 |
26.55 |
| 2026-05-19 00:00 |
13:03:56.85 |
+76:24:59.4 |
HIP 63200 |
25.53 |
| 2026-05-19 12:00 |
13:03:41.83 |
+76:24:17.7 |
HIP 63200 |
24.53 |
| 2026-05-20 00:00 |
13:03:26.97 |
+76:23:35.4 |
HIP 63200 |
23.54 |
| 2026-05-20 12:00 |
13:03:12.25 |
+76:22:52.5 |
HIP 63200 |
22.57 |
| 2026-05-21 00:00 |
13:02:57.69 |
+76:22:09.1 |
HIP 63200 |
21.63 |
| 2026-05-21 12:00 |
13:02:43.29 |
+76:21:25.1 |
HIP 63200 |
20.70 |
| 2026-05-22 00:00 |
13:02:29.04 |
+76:20:40.6 |
HIP 63200 |
19.81 |
| 2026-05-22 12:00 |
13:02:14.95 |
+76:19:55.5 |
HIP 63200 |
18.95 |
| 2026-05-23 00:00 |
13:02:01.01 |
+76:19:10.0 |
HIP 63200 |
18.12 |
| 2026-05-23 12:00 |
13:01:47.23 |
+76:18:23.8 |
HIP 63200 |
17.33 |
| 2026-05-24 00:00 |
13:01:33.61 |
+76:17:37.2 |
HIP 63200 |
16.60 |
| 2026-05-24 12:00 |
13:01:20.15 |
+76:16:50.1 |
HIP 63200 |
15.91 |
| 2026-05-25 00:00 |
13:01:06.86 |
+76:16:02.4 |
HIP 63200 |
15.29 |
| 2026-05-25 12:00 |
13:00:53.72 |
+76:15:14.2 |
HIP 63200 |
14.73 |
| 2026-05-26 00:00 |
13:00:40.74 |
+76:14:25.6 |
HIP 63200 |
14.26 |
| 2026-05-26 12:00 |
13:00:27.92 |
+76:13:36.5 |
HIP 63200 |
13.86 |
| 2026-05-27 00:00 |
13:00:15.27 |
+76:12:46.8 |
HIP 63200 |
13.56 |
| 2026-05-27 12:00 |
13:00:02.78 |
+76:11:56.7 |
HIP 63200 |
13.36 |
| 2026-05-28 00:00 |
12:59:50.46 |
+76:11:06.1 |
HIP 63200 |
13.26 |
| 2026-05-28 12:00 |
12:59:38.30 |
+76:10:15.1 |
HIP 63200 |
13.27 |
| 2026-05-29 00:00 |
12:59:26.30 |
+76:09:23.6 |
HIP 63200 |
13.37 |
| 2026-05-29 12:00 |
12:59:14.47 |
+76:08:31.6 |
HIP 63200 |
13.59 |
| 2026-05-30 00:00 |
12:59:02.81 |
+76:07:39.2 |
HIP 63200 |
13.90 |
| 2026-05-30 12:00 |
12:58:51.31 |
+76:06:46.4 |
HIP 63200 |
14.30 |
| 2026-05-31 00:00 |
12:58:39.98 |
+76:05:53.1 |
HIP 63200 |
14.78 |
| 2026-05-31 12:00 |
12:58:28.82 |
+76:04:59.4 |
HIP 63200 |
15.34 |
| 2026-06-01 00:00 |
12:58:17.82 |
+76:04:05.2 |
HIP 63200 |
15.97 |
| 2026-06-01 12:00 |
12:58:07.00 |
+76:03:10.6 |
HIP 63200 |
16.66 |
| 2026-06-02 00:00 |
12:57:56.34 |
+76:02:15.6 |
HIP 63200 |
17.40 |