メタデータ
| 項目 |
値 |
| Designation |
C/2015 V2 (Johnson) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2017-06-12T08:20:20.423040Z |
| Orbit solution date (soln_date, UTC) |
2026-06-09T11:12:24Z |
| Obs used |
5890 |
| NEO |
- |
| M1 |
10.000 |
| K1 |
4.500 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2017-01-18.0000000 |
| e |
1.00170261 |
| q (au) |
1.636950 |
| a (au) |
-961.433151 |
| i (deg) |
49.874812 |
| Ω (om, deg) |
69.852100 |
| ω (w, deg) |
164.898098 |
| M (ma, deg) |
-0.004805 |
等級
散乱 + 全体線形
$$
M_a = (12.183 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
12.183 |
| n |
2.000 |
| gf |
0.999 |
| gb |
-0.781 |
| 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
残差 (区間線形)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| 開始日 (UTC) |
終了日 (UTC) |
a |
b |
| 2015-01-11 |
2017-06-11 |
+1.6631 |
-1.343 |
| 2017-06-12 |
2017-08-29 |
-9.8516 |
+0.988 |
| 2017-08-29 |
2019-10-27 |
+2.9922 |
-2.101 |
log10 r = log10(太陽距離/AU)、Δ = 地球距離(AU)
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-09-20 00:00 |
03:07:33.78 |
-18:24:17.0 |
HIP 14674 |
35.34 |
| 2026-09-20 12:00 |
03:07:30.67 |
-18:24:58.1 |
HIP 14635 |
35.98 |
| 2026-09-21 00:00 |
03:07:27.52 |
-18:25:38.9 |
HIP 14635 |
35.95 |
| 2026-09-21 12:00 |
03:07:24.33 |
-18:26:19.7 |
HIP 14635 |
35.94 |
| 2026-09-22 00:00 |
03:07:21.11 |
-18:27:00.3 |
HIP 14635 |
35.97 |
| 2026-09-22 12:00 |
03:07:17.85 |
-18:27:40.8 |
HIP 14635 |
36.04 |
| 2026-09-23 00:00 |
03:07:14.55 |
-18:28:21.2 |
HIP 14635 |
36.15 |
| 2026-09-23 12:00 |
03:07:11.22 |
-18:29:01.4 |
HIP 14635 |
36.29 |
| 2026-09-24 00:00 |
03:07:07.86 |
-18:29:41.5 |
HIP 14635 |
36.47 |
| 2026-09-24 12:00 |
03:07:04.46 |
-18:30:21.4 |
HIP 14635 |
36.68 |
| 2026-09-25 00:00 |
03:07:01.03 |
-18:31:01.2 |
HIP 14635 |
36.94 |
| 2026-09-25 12:00 |
03:06:57.56 |
-18:31:40.8 |
HIP 14635 |
37.22 |
| 2026-09-26 00:00 |
03:06:54.06 |
-18:32:20.3 |
HIP 14635 |
37.55 |
| 2026-09-26 12:00 |
03:06:50.52 |
-18:32:59.6 |
HIP 14635 |
37.90 |
| 2026-09-27 00:00 |
03:06:46.95 |
-18:33:38.8 |
HIP 14635 |
38.30 |
| 2026-09-27 12:00 |
03:06:43.35 |
-18:34:17.7 |
HIP 14357 |
37.31 |
| 2026-09-28 00:00 |
03:06:39.72 |
-18:34:56.5 |
HIP 14357 |
36.29 |
| 2026-09-28 12:00 |
03:06:36.05 |
-18:35:35.2 |
HIP 14357 |
35.27 |
| 2026-09-29 00:00 |
03:06:32.35 |
-18:36:13.6 |
HIP 14357 |
34.25 |
| 2026-09-29 12:00 |
03:06:28.62 |
-18:36:51.9 |
HIP 14357 |
33.24 |
| 2026-09-30 00:00 |
03:06:24.86 |
-18:37:30.0 |
HIP 14357 |
32.22 |
| 2026-09-30 12:00 |
03:06:21.06 |
-18:38:07.8 |
HIP 14357 |
31.21 |
| 2026-10-01 00:00 |
03:06:17.24 |
-18:38:45.5 |
HIP 14357 |
30.21 |
| 2026-10-01 12:00 |
03:06:13.38 |
-18:39:23.0 |
HIP 14357 |
29.22 |
| 2026-10-02 00:00 |
03:06:09.49 |
-18:40:00.3 |
HIP 14357 |
28.23 |
| 2026-10-02 12:00 |
03:06:05.57 |
-18:40:37.4 |
HIP 14357 |
27.25 |
| 2026-10-03 00:00 |
03:06:01.62 |
-18:41:14.3 |
HIP 14357 |
26.28 |
| 2026-10-03 12:00 |
03:05:57.64 |
-18:41:51.0 |
HIP 14357 |
25.32 |
| 2026-10-04 00:00 |
03:05:53.64 |
-18:42:27.5 |
HIP 14357 |
24.38 |
| 2026-10-04 12:00 |
03:05:49.60 |
-18:43:03.7 |
HIP 14357 |
23.46 |
| 2026-10-05 00:00 |
03:05:45.53 |
-18:43:39.8 |
HIP 14357 |
22.56 |
| 2026-10-05 12:00 |
03:05:41.44 |
-18:44:15.5 |
HIP 14357 |
21.67 |
| 2026-10-06 00:00 |
03:05:37.31 |
-18:44:51.1 |
HIP 14357 |
20.82 |
| 2026-10-06 12:00 |
03:05:33.16 |
-18:45:26.4 |
HIP 14357 |
20.00 |
| 2026-10-07 00:00 |
03:05:28.98 |
-18:46:01.5 |
HIP 14357 |
19.21 |
| 2026-10-07 12:00 |
03:05:24.78 |
-18:46:36.4 |
HIP 14357 |
18.46 |
| 2026-10-08 00:00 |
03:05:20.54 |
-18:47:11.0 |
HIP 14357 |
17.76 |
| 2026-10-08 12:00 |
03:05:16.28 |
-18:47:45.4 |
HIP 14357 |
17.12 |
| 2026-10-09 00:00 |
03:05:12.00 |
-18:48:19.5 |
HIP 14357 |
16.53 |
| 2026-10-09 12:00 |
03:05:07.69 |
-18:48:53.3 |
HIP 14357 |
16.01 |
| 2026-10-10 00:00 |
03:05:03.35 |
-18:49:26.9 |
HIP 14357 |
15.57 |
| 2026-10-10 12:00 |
03:04:58.98 |
-18:50:00.2 |
HIP 14357 |
15.21 |
| 2026-10-11 00:00 |
03:04:54.60 |
-18:50:33.3 |
HIP 14357 |
14.94 |