メタデータ
| 項目 |
値 |
| Designation |
C/2018 B1 (Lemmon) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2018-03-30T10:39:55.339200Z |
| Orbit solution date (soln_date, UTC) |
2022-07-19T01:12:15Z |
| Obs used |
316 |
| NEO |
- |
| M1 |
12.300 |
| 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) |
2018-10-22.0000000 |
| e |
1.00296934 |
| q (au) |
5.116718 |
| a (au) |
-1723.183540 |
| i (deg) |
162.423569 |
| Ω (om, deg) |
133.168875 |
| ω (w, deg) |
68.349093 |
| M (ma, deg) |
0.002832 |
等級
散乱 + 全体線形
$$
M_a = (15.479 + 2.127\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
15.479 |
| n |
2.127 |
| gf |
1.000 |
| gb |
-0.810 |
| 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 |
| 2017-01-16 |
2018-03-03 |
+44.9933 |
-31.597 |
| 2018-08-17 |
2019-10-31 |
+3.0484 |
-2.392 |
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 |
20:40:41.34 |
-20:24:46.6 |
HIP 101952 |
24.69 |
| 2026-07-29 12:00 |
20:40:33.78 |
-20:25:19.8 |
HIP 101952 |
24.09 |
| 2026-07-30 00:00 |
20:40:26.23 |
-20:25:53.0 |
HIP 101952 |
23.62 |
| 2026-07-30 12:00 |
20:40:18.67 |
-20:26:26.1 |
HIP 101952 |
23.29 |
| 2026-07-31 00:00 |
20:40:11.12 |
-20:26:59.2 |
HIP 101952 |
23.11 |
| 2026-07-31 12:00 |
20:40:03.56 |
-20:27:32.2 |
HIP 101952 |
23.07 |
| 2026-08-01 00:00 |
20:39:56.01 |
-20:28:05.1 |
HIP 101952 |
23.18 |
| 2026-08-01 12:00 |
20:39:48.46 |
-20:28:38.0 |
HIP 101952 |
23.43 |
| 2026-08-02 00:00 |
20:39:40.91 |
-20:29:10.9 |
HIP 101952 |
23.83 |
| 2026-08-02 12:00 |
20:39:33.37 |
-20:29:43.6 |
HIP 101952 |
24.36 |
| 2026-08-03 00:00 |
20:39:25.82 |
-20:30:16.3 |
HIP 101952 |
25.01 |
| 2026-08-03 12:00 |
20:39:18.29 |
-20:30:48.9 |
HIP 101952 |
25.78 |
| 2026-08-04 00:00 |
20:39:10.75 |
-20:31:21.5 |
HIP 101952 |
26.66 |
| 2026-08-04 12:00 |
20:39:03.23 |
-20:31:54.0 |
HIP 101952 |
27.63 |
| 2026-08-05 00:00 |
20:38:55.70 |
-20:32:26.4 |
HIP 101858 |
28.11 |
| 2026-08-05 12:00 |
20:38:48.19 |
-20:32:58.7 |
HIP 101858 |
27.19 |
| 2026-08-06 00:00 |
20:38:40.68 |
-20:33:30.9 |
HIP 101858 |
26.37 |
| 2026-08-06 12:00 |
20:38:33.18 |
-20:34:03.1 |
HIP 101858 |
25.65 |
| 2026-08-07 00:00 |
20:38:25.69 |
-20:34:35.2 |
HIP 101858 |
25.05 |
| 2026-08-07 12:00 |
20:38:18.20 |
-20:35:07.2 |
HIP 101858 |
24.58 |
| 2026-08-08 00:00 |
20:38:10.72 |
-20:35:39.1 |
HIP 101858 |
24.23 |
| 2026-08-08 12:00 |
20:38:03.26 |
-20:36:10.9 |
HIP 101666 |
22.68 |
| 2026-08-09 00:00 |
20:37:55.80 |
-20:36:42.6 |
HIP 101666 |
20.97 |
| 2026-08-09 12:00 |
20:37:48.36 |
-20:37:14.2 |
HIP 101666 |
19.28 |
| 2026-08-10 00:00 |
20:37:40.92 |
-20:37:45.8 |
HIP 101666 |
17.62 |
| 2026-08-10 12:00 |
20:37:33.50 |
-20:38:17.2 |
HIP 101666 |
16.00 |
| 2026-08-11 00:00 |
20:37:26.09 |
-20:38:48.6 |
HIP 101666 |
14.43 |
| 2026-08-11 12:00 |
20:37:18.69 |
-20:39:19.8 |
HIP 101666 |
12.92 |
| 2026-08-12 00:00 |
20:37:11.31 |
-20:39:50.9 |
HIP 101666 |
11.51 |
| 2026-08-12 12:00 |
20:37:03.94 |
-20:40:21.9 |
HIP 101666 |
10.21 |
| 2026-08-13 00:00 |
20:36:56.59 |
-20:40:52.9 |
HIP 101666 |
9.10 |
| 2026-08-13 12:00 |
20:36:49.25 |
-20:41:23.7 |
HIP 101666 |
8.23 |
| 2026-08-14 00:00 |
20:36:41.93 |
-20:41:54.4 |
HIP 101666 |
7.68 |
| 2026-08-14 12:00 |
20:36:34.62 |
-20:42:24.9 |
HIP 101666 |
7.53 |
| 2026-08-15 00:00 |
20:36:27.34 |
-20:42:55.4 |
HIP 101666 |
7.80 |
| 2026-08-15 12:00 |
20:36:20.07 |
-20:43:25.8 |
HIP 101666 |
8.44 |
| 2026-08-16 00:00 |
20:36:12.81 |
-20:43:56.0 |
HIP 101666 |
9.37 |
| 2026-08-16 12:00 |
20:36:05.58 |
-20:44:26.1 |
HIP 101666 |
10.51 |
| 2026-08-17 00:00 |
20:35:58.37 |
-20:44:56.1 |
HIP 101666 |
11.81 |
| 2026-08-17 12:00 |
20:35:51.17 |
-20:45:25.9 |
HIP 101666 |
13.20 |
| 2026-08-18 00:00 |
20:35:44.00 |
-20:45:55.7 |
HIP 101666 |
14.67 |
| 2026-08-18 12:00 |
20:35:36.85 |
-20:46:25.3 |
HIP 101666 |
16.19 |
| 2026-08-19 00:00 |
20:35:29.72 |
-20:46:54.7 |
HIP 101666 |
17.75 |