メタデータ
| 項目 |
値 |
| Designation |
C/2018 V1 (Machholz-Fujikawa-Iwamoto) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2018-12-03T12:11:39.986880Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:46Z |
| Obs used |
750 |
| NEO |
- |
| M1 |
12.800 |
| K1 |
6.250 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2018-11-16.0000000 |
| e |
1.00039061 |
| q (au) |
0.386955 |
| a (au) |
-990.650949 |
| i (deg) |
143.987960 |
| Ω (om, deg) |
128.722091 |
| ω (w, deg) |
88.774914 |
| M (ma, deg) |
-0.000553 |
等級
散乱 + 全体線形
$$
M_a = (12.888 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
12.888 |
| n |
2.000 |
| gf |
0.800 |
| gb |
-1.000 |
| k |
0.800 |
| δ90 |
1.000 |
| 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 |
| 2018-11-08 |
2018-11-17 |
-1.9894 |
-0.711 |
| 2018-11-17 |
2018-12-01 |
+3.0505 |
+1.813 |
| 2018-12-04 |
2018-12-17 |
+11.8201 |
+5.111 |
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) |
| 2026-07-29 00:00 |
14:43:34.11 |
-52:35:23.1 |
HIP 71947 |
6.80 |
| 2026-07-29 12:00 |
14:43:32.78 |
-52:34:31.1 |
HIP 71947 |
7.10 |
| 2026-07-30 00:00 |
14:43:31.54 |
-52:33:39.3 |
HIP 71947 |
7.51 |
| 2026-07-30 12:00 |
14:43:30.36 |
-52:32:47.7 |
HIP 71947 |
7.99 |
| 2026-07-31 00:00 |
14:43:29.27 |
-52:31:56.2 |
HIP 71947 |
8.55 |
| 2026-07-31 12:00 |
14:43:28.24 |
-52:31:04.9 |
HIP 71947 |
9.16 |
| 2026-08-01 00:00 |
14:43:27.29 |
-52:30:13.7 |
HIP 71947 |
9.81 |
| 2026-08-01 12:00 |
14:43:26.41 |
-52:29:22.8 |
HIP 71947 |
10.49 |
| 2026-08-02 00:00 |
14:43:25.61 |
-52:28:32.0 |
HIP 71947 |
11.20 |
| 2026-08-02 12:00 |
14:43:24.88 |
-52:27:41.4 |
HIP 71947 |
11.94 |
| 2026-08-03 00:00 |
14:43:24.22 |
-52:26:50.9 |
HIP 71947 |
12.68 |
| 2026-08-03 12:00 |
14:43:23.63 |
-52:26:00.7 |
HIP 71947 |
13.44 |
| 2026-08-04 00:00 |
14:43:23.12 |
-52:25:10.7 |
HIP 71947 |
14.21 |
| 2026-08-04 12:00 |
14:43:22.69 |
-52:24:20.8 |
HIP 71947 |
14.99 |
| 2026-08-05 00:00 |
14:43:22.32 |
-52:23:31.2 |
HIP 71947 |
15.77 |
| 2026-08-05 12:00 |
14:43:22.03 |
-52:22:41.7 |
HIP 71947 |
16.55 |
| 2026-08-06 00:00 |
14:43:21.81 |
-52:21:52.5 |
HIP 71947 |
17.34 |
| 2026-08-06 12:00 |
14:43:21.66 |
-52:21:03.4 |
HIP 71947 |
18.13 |
| 2026-08-07 00:00 |
14:43:21.59 |
-52:20:14.6 |
HIP 71947 |
18.93 |
| 2026-08-07 12:00 |
14:43:21.59 |
-52:19:26.0 |
HIP 71947 |
19.72 |
| 2026-08-08 00:00 |
14:43:21.66 |
-52:18:37.6 |
HIP 72039 |
20.38 |
| 2026-08-08 12:00 |
14:43:21.80 |
-52:17:49.4 |
HIP 72039 |
19.63 |
| 2026-08-09 00:00 |
14:43:22.02 |
-52:17:01.5 |
HIP 72039 |
18.88 |
| 2026-08-09 12:00 |
14:43:22.30 |
-52:16:13.8 |
HIP 72039 |
18.13 |
| 2026-08-10 00:00 |
14:43:22.66 |
-52:15:26.3 |
HIP 72039 |
17.38 |
| 2026-08-10 12:00 |
14:43:23.09 |
-52:14:39.1 |
HIP 72039 |
16.64 |
| 2026-08-11 00:00 |
14:43:23.60 |
-52:13:52.1 |
HIP 72039 |
15.90 |
| 2026-08-11 12:00 |
14:43:24.17 |
-52:13:05.3 |
HIP 72039 |
15.17 |
| 2026-08-12 00:00 |
14:43:24.81 |
-52:12:18.8 |
HIP 72039 |
14.43 |
| 2026-08-12 12:00 |
14:43:25.53 |
-52:11:32.6 |
HIP 72039 |
13.71 |
| 2026-08-13 00:00 |
14:43:26.32 |
-52:10:46.5 |
HIP 72039 |
12.98 |
| 2026-08-13 12:00 |
14:43:27.17 |
-52:10:00.8 |
HIP 72039 |
12.26 |
| 2026-08-14 00:00 |
14:43:28.10 |
-52:09:15.3 |
HIP 72039 |
11.55 |
| 2026-08-14 12:00 |
14:43:29.10 |
-52:08:30.1 |
HIP 72039 |
10.84 |
| 2026-08-15 00:00 |
14:43:30.17 |
-52:07:45.1 |
HIP 72039 |
10.13 |
| 2026-08-15 12:00 |
14:43:31.31 |
-52:07:00.4 |
HIP 72039 |
9.43 |
| 2026-08-16 00:00 |
14:43:32.51 |
-52:06:16.0 |
HIP 72039 |
8.74 |
| 2026-08-16 12:00 |
14:43:33.79 |
-52:05:31.8 |
HIP 72039 |
8.06 |
| 2026-08-17 00:00 |
14:43:35.13 |
-52:04:48.0 |
HIP 72039 |
7.39 |
| 2026-08-17 12:00 |
14:43:36.55 |
-52:04:04.4 |
HIP 72039 |
6.74 |
| 2026-08-18 00:00 |
14:43:38.03 |
-52:03:21.0 |
HIP 72039 |
6.10 |
| 2026-08-18 12:00 |
14:43:39.58 |
-52:02:38.0 |
HIP 72039 |
5.49 |
| 2026-08-19 00:00 |
14:43:41.19 |
-52:01:55.3 |
HIP 72039 |
4.91 |