メタデータ
| 項目 |
値 |
| Designation |
C/2017 A3 (Elenin) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2017-01-30T14:31:52.288320Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:28Z |
| Obs used |
186 |
| NEO |
- |
| M1 |
9.700 |
| K1 |
10.000 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2017-02-10.0000000 |
| e |
0.91107616 |
| q (au) |
3.854543 |
| a (au) |
43.346563 |
| i (deg) |
98.508477 |
| Ω (om, deg) |
97.903943 |
| ω (w, deg) |
304.107532 |
| M (ma, deg) |
0.035899 |
等級
散乱 + 全体線形
$$
M_a = (5.803 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
5.803 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.971 |
| 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) |
| 2026-03-26 00:00 |
20:56:22.76 |
+76:30:50.1 |
HIP 103219 |
35.79 |
| 2026-03-26 12:00 |
20:56:35.40 |
+76:31:50.2 |
HIP 104149 |
36.85 |
| 2026-03-27 00:00 |
20:56:47.89 |
+76:32:50.6 |
HIP 104213 |
36.40 |
| 2026-03-27 12:00 |
20:57:00.24 |
+76:33:51.5 |
HIP 104213 |
35.95 |
| 2026-03-28 00:00 |
20:57:12.44 |
+76:34:52.7 |
HIP 104147 |
35.00 |
| 2026-03-28 12:00 |
20:57:24.50 |
+76:35:54.3 |
HIP 104147 |
33.88 |
| 2026-03-29 00:00 |
20:57:36.40 |
+76:36:56.3 |
HIP 104147 |
32.77 |
| 2026-03-29 12:00 |
20:57:48.16 |
+76:37:58.7 |
HIP 104147 |
31.67 |
| 2026-03-30 00:00 |
20:57:59.76 |
+76:39:01.5 |
HIP 104147 |
30.60 |
| 2026-03-30 12:00 |
20:58:11.22 |
+76:40:04.6 |
HIP 104147 |
29.54 |
| 2026-03-31 00:00 |
20:58:22.52 |
+76:41:08.0 |
HIP 104147 |
28.50 |
| 2026-03-31 12:00 |
20:58:33.67 |
+76:42:11.9 |
HIP 104147 |
27.49 |
| 2026-04-01 00:00 |
20:58:44.66 |
+76:43:16.1 |
HIP 104147 |
26.51 |
| 2026-04-01 12:00 |
20:58:55.49 |
+76:44:20.6 |
HIP 104147 |
25.56 |
| 2026-04-02 00:00 |
20:59:06.17 |
+76:45:25.5 |
HIP 104147 |
24.64 |
| 2026-04-02 12:00 |
20:59:16.69 |
+76:46:30.7 |
HIP 104147 |
23.76 |
| 2026-04-03 00:00 |
20:59:27.06 |
+76:47:36.3 |
HIP 104147 |
22.92 |
| 2026-04-03 12:00 |
20:59:37.26 |
+76:48:42.2 |
HIP 104147 |
22.13 |
| 2026-04-04 00:00 |
20:59:47.30 |
+76:49:48.4 |
HIP 104147 |
21.39 |
| 2026-04-04 12:00 |
20:59:57.18 |
+76:50:55.0 |
HIP 104147 |
20.71 |
| 2026-04-05 00:00 |
21:00:06.89 |
+76:52:01.8 |
HIP 104147 |
20.09 |
| 2026-04-05 12:00 |
21:00:16.44 |
+76:53:09.0 |
HIP 104147 |
19.55 |
| 2026-04-06 00:00 |
21:00:25.83 |
+76:54:16.5 |
HIP 104147 |
19.08 |
| 2026-04-06 12:00 |
21:00:35.04 |
+76:55:24.3 |
HIP 104147 |
18.70 |
| 2026-04-07 00:00 |
21:00:44.09 |
+76:56:32.5 |
HIP 104147 |
18.40 |
| 2026-04-07 12:00 |
21:00:52.97 |
+76:57:40.9 |
HIP 104147 |
18.20 |
| 2026-04-08 00:00 |
21:01:01.67 |
+76:58:49.6 |
HIP 104147 |
18.10 |
| 2026-04-08 12:00 |
21:01:10.21 |
+76:59:58.6 |
HIP 104147 |
18.09 |
| 2026-04-09 00:00 |
21:01:18.57 |
+77:01:07.9 |
HIP 104147 |
18.18 |
| 2026-04-09 12:00 |
21:01:26.76 |
+77:02:17.5 |
HIP 104147 |
18.36 |
| 2026-04-10 00:00 |
21:01:34.77 |
+77:03:27.3 |
HIP 104147 |
18.64 |
| 2026-04-10 12:00 |
21:01:42.60 |
+77:04:37.5 |
HIP 104147 |
19.01 |
| 2026-04-11 00:00 |
21:01:50.26 |
+77:05:47.9 |
HIP 104147 |
19.46 |
| 2026-04-11 12:00 |
21:01:57.73 |
+77:06:58.5 |
HIP 104147 |
20.00 |
| 2026-04-12 00:00 |
21:02:05.03 |
+77:08:09.5 |
HIP 104147 |
20.60 |
| 2026-04-12 12:00 |
21:02:12.14 |
+77:09:20.6 |
HIP 103628 |
19.69 |
| 2026-04-13 00:00 |
21:02:19.07 |
+77:10:32.1 |
HIP 103628 |
18.77 |
| 2026-04-13 12:00 |
21:02:25.81 |
+77:11:43.7 |
HIP 103628 |
17.89 |
| 2026-04-14 00:00 |
21:02:32.37 |
+77:12:55.6 |
HIP 103628 |
17.03 |
| 2026-04-14 12:00 |
21:02:38.74 |
+77:14:07.8 |
HIP 103628 |
16.22 |
| 2026-04-15 00:00 |
21:02:44.92 |
+77:15:20.2 |
HIP 103628 |
15.46 |
| 2026-04-15 12:00 |
21:02:50.91 |
+77:16:32.8 |
HIP 103628 |
14.76 |
| 2026-04-16 00:00 |
21:02:56.70 |
+77:17:45.6 |
HIP 103628 |
14.12 |