C/2018 L2 (ATLAS)
メタデータ
| 項目 |
値 |
| Designation |
C/2018 L2 (ATLAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2018-12-02T13:55:55.485120Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:44Z |
| Obs used |
731 |
| NEO |
- |
| M1 |
9.500 |
| K1 |
10.750 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2018-06-06T07:58:35.040000Z |
| Discovery magnitude (MPC) |
15.60 o |
| Discovery observatory (MPC) |
T08 · ATLAS-MLO, Mauna Loa |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2018-12-29.0000000 |
| e |
0.99298130 |
| q (au) |
1.711711 |
| a (au) |
243.878556 |
| i (deg) |
67.423590 |
| Ω (om, deg) |
243.018259 |
| ω (w, deg) |
56.230818 |
| M (ma, deg) |
0.006837 |
等級
散乱 + 全体線形
$$
M_a = (8.836 + 4.978\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
8.836 |
| n |
4.978 |
| gf |
1.000 |
| gb |
-0.767 |
| k |
0.985 |
| 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 |
| 2018-06-04 |
2018-09-08 |
+4.1202 |
-1.557 |
| 2018-09-08 |
2018-12-01 |
+25.5943 |
-7.920 |
| 2018-12-03 |
2020-01-20 |
+2.8927 |
-2.045 |
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) |
| 2026-02-03 00:00 |
04:42:02.74 |
+01:14:24.2 |
HIP 21944 |
16.45 |
| 2026-02-03 12:00 |
04:42:00.12 |
+01:14:41.4 |
HIP 21944 |
17.16 |
| 2026-02-04 00:00 |
04:41:57.56 |
+01:14:58.7 |
HIP 21944 |
17.86 |
| 2026-02-04 12:00 |
04:41:55.04 |
+01:15:16.3 |
HIP 21944 |
18.55 |
| 2026-02-05 00:00 |
04:41:52.58 |
+01:15:34.1 |
HIP 21944 |
19.23 |
| 2026-02-05 12:00 |
04:41:50.17 |
+01:15:52.1 |
HIP 21944 |
19.90 |
| 2026-02-06 00:00 |
04:41:47.81 |
+01:16:10.3 |
HIP 21944 |
20.57 |
| 2026-02-06 12:00 |
04:41:45.50 |
+01:16:28.6 |
HIP 21944 |
21.22 |
| 2026-02-07 00:00 |
04:41:43.25 |
+01:16:47.2 |
HIP 21944 |
21.86 |
| 2026-02-07 12:00 |
04:41:41.05 |
+01:17:06.0 |
HIP 21795 |
22.35 |
| 2026-02-08 00:00 |
04:41:38.90 |
+01:17:25.0 |
HIP 21795 |
22.36 |
| 2026-02-08 12:00 |
04:41:36.80 |
+01:17:44.2 |
HIP 21795 |
22.40 |
| 2026-02-09 00:00 |
04:41:34.76 |
+01:18:03.5 |
HIP 21795 |
22.46 |
| 2026-02-09 12:00 |
04:41:32.77 |
+01:18:23.1 |
HIP 21795 |
22.55 |
| 2026-02-10 00:00 |
04:41:30.83 |
+01:18:42.8 |
HIP 21795 |
22.66 |
| 2026-02-10 12:00 |
04:41:28.95 |
+01:19:02.7 |
HIP 21795 |
22.80 |
| 2026-02-11 00:00 |
04:41:27.12 |
+01:19:22.8 |
HIP 21795 |
22.95 |
| 2026-02-11 12:00 |
04:41:25.34 |
+01:19:43.1 |
HIP 21795 |
23.13 |
| 2026-02-12 00:00 |
04:41:23.62 |
+01:20:03.6 |
HIP 21795 |
23.32 |
| 2026-02-12 12:00 |
04:41:21.95 |
+01:20:24.2 |
HIP 21795 |
23.53 |
| 2026-02-13 00:00 |
04:41:20.33 |
+01:20:45.0 |
HIP 21795 |
23.76 |
| 2026-02-13 12:00 |
04:41:18.77 |
+01:21:05.9 |
HIP 21795 |
24.00 |
| 2026-02-14 00:00 |
04:41:17.26 |
+01:21:27.1 |
HIP 21795 |
24.26 |
| 2026-02-14 12:00 |
04:41:15.80 |
+01:21:48.3 |
HIP 21795 |
24.53 |
| 2026-02-15 00:00 |
04:41:14.40 |
+01:22:09.8 |
HIP 21795 |
24.82 |
| 2026-02-15 12:00 |
04:41:13.05 |
+01:22:31.4 |
HIP 21795 |
25.11 |
| 2026-02-16 00:00 |
04:41:11.76 |
+01:22:53.2 |
HIP 21795 |
25.42 |
| 2026-02-16 12:00 |
04:41:10.52 |
+01:23:15.1 |
HIP 21795 |
25.73 |
| 2026-02-17 00:00 |
04:41:09.34 |
+01:23:37.1 |
HIP 21795 |
26.06 |
| 2026-02-17 12:00 |
04:41:08.21 |
+01:23:59.3 |
HIP 21795 |
26.39 |
| 2026-02-18 00:00 |
04:41:07.13 |
+01:24:21.7 |
HIP 21795 |
26.73 |
| 2026-02-18 12:00 |
04:41:06.11 |
+01:24:44.2 |
HIP 21795 |
27.08 |
| 2026-02-19 00:00 |
04:41:05.14 |
+01:25:06.8 |
HIP 21795 |
27.44 |
| 2026-02-19 12:00 |
04:41:04.23 |
+01:25:29.6 |
HIP 21795 |
27.80 |
| 2026-02-20 00:00 |
04:41:03.37 |
+01:25:52.5 |
HIP 21795 |
28.16 |
| 2026-02-20 12:00 |
04:41:02.57 |
+01:26:15.5 |
HIP 21795 |
28.54 |
| 2026-02-21 00:00 |
04:41:01.82 |
+01:26:38.6 |
HIP 21826 |
28.37 |
| 2026-02-21 12:00 |
04:41:01.12 |
+01:27:01.9 |
HIP 21826 |
28.04 |
| 2026-02-22 00:00 |
04:41:00.48 |
+01:27:25.3 |
HIP 21826 |
27.71 |
| 2026-02-22 12:00 |
04:40:59.89 |
+01:27:48.8 |
HIP 21826 |
27.38 |
| 2026-02-23 00:00 |
04:40:59.36 |
+01:28:12.5 |
HIP 21826 |
27.04 |
| 2026-02-23 12:00 |
04:40:58.88 |
+01:28:36.2 |
HIP 21826 |
26.70 |
| 2026-02-24 00:00 |
04:40:58.45 |
+01:29:00.1 |
HIP 21826 |
26.36 |