メタデータ
| 項目 |
値 |
| Designation |
C/2018 S2 (TESS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2018-11-05T04:38:14.709120Z |
| Orbit solution date (soln_date, UTC) |
2022-08-25T20:42:05Z |
| Obs used |
803 |
| NEO |
- |
| M1 |
6.700 |
| K1 |
11.000 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2018-09-23T18:44:41.078400Z |
| Discovery magnitude (MPC) |
18.50 G |
| Discovery observatory (MPC) |
C57 · TESS |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2018-04-11.0000000 |
| e |
0.61491477 |
| q (au) |
5.470619 |
| a (au) |
14.206254 |
| i (deg) |
64.220443 |
| Ω (om, deg) |
85.125919 |
| ω (w, deg) |
290.683496 |
| M (ma, deg) |
356.167772 |
等級
散乱 + 全体線形
$$
M_a = (8.539 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
8.539 |
| n |
6.000 |
| gf |
0.973 |
| gb |
-0.935 |
| k |
0.800 |
| δ90 |
9.920 |
| 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) |
| 2026-06-01 00:00 |
08:47:20.64 |
+65:44:13.2 |
HIP 43094 |
17.50 |
| 2026-06-01 12:00 |
08:47:34.51 |
+65:42:57.1 |
HIP 43094 |
16.74 |
| 2026-06-02 00:00 |
08:47:48.48 |
+65:41:41.3 |
HIP 43094 |
16.17 |
| 2026-06-02 12:00 |
08:48:02.55 |
+65:40:25.6 |
HIP 43094 |
15.83 |
| 2026-06-03 00:00 |
08:48:16.73 |
+65:39:10.2 |
HIP 43094 |
15.73 |
| 2026-06-03 12:00 |
08:48:31.02 |
+65:37:55.1 |
HIP 43094 |
15.88 |
| 2026-06-04 00:00 |
08:48:45.40 |
+65:36:40.1 |
HIP 43094 |
16.28 |
| 2026-06-04 12:00 |
08:48:59.89 |
+65:35:25.4 |
HIP 43094 |
16.90 |
| 2026-06-05 00:00 |
08:49:14.48 |
+65:34:11.0 |
HIP 43094 |
17.73 |
| 2026-06-05 12:00 |
08:49:29.17 |
+65:32:56.8 |
HIP 43094 |
18.74 |
| 2026-06-06 00:00 |
08:49:43.97 |
+65:31:42.8 |
HIP 43094 |
19.91 |
| 2026-06-06 12:00 |
08:49:58.86 |
+65:30:29.1 |
HIP 43094 |
21.20 |
| 2026-06-07 00:00 |
08:50:13.84 |
+65:29:15.6 |
HIP 43094 |
22.61 |
| 2026-06-07 12:00 |
08:50:28.93 |
+65:28:02.4 |
HIP 43094 |
24.12 |
| 2026-06-08 00:00 |
08:50:44.11 |
+65:26:49.4 |
HIP 43094 |
25.70 |
| 2026-06-08 12:00 |
08:50:59.39 |
+65:25:36.7 |
HIP 43586 |
27.00 |
| 2026-06-09 00:00 |
08:51:14.76 |
+65:24:24.2 |
HIP 43586 |
27.61 |
| 2026-06-09 12:00 |
08:51:30.23 |
+65:23:12.1 |
HIP 43586 |
28.33 |
| 2026-06-10 00:00 |
08:51:45.79 |
+65:22:00.2 |
HIP 43586 |
29.17 |
| 2026-06-10 12:00 |
08:52:01.44 |
+65:20:48.5 |
HIP 43586 |
30.11 |
| 2026-06-11 00:00 |
08:52:17.18 |
+65:19:37.2 |
HIP 43399 |
30.16 |
| 2026-06-11 12:00 |
08:52:33.02 |
+65:18:26.1 |
HIP 43399 |
29.79 |
| 2026-06-12 00:00 |
08:52:48.94 |
+65:17:15.3 |
HIP 43928 |
29.30 |
| 2026-06-12 12:00 |
08:53:04.95 |
+65:16:04.8 |
HIP 43928 |
28.49 |
| 2026-06-13 00:00 |
08:53:21.05 |
+65:14:54.6 |
HIP 43928 |
27.79 |
| 2026-06-13 12:00 |
08:53:37.24 |
+65:13:44.7 |
HIP 43928 |
27.21 |
| 2026-06-14 00:00 |
08:53:53.52 |
+65:12:35.0 |
HIP 43928 |
26.77 |
| 2026-06-14 12:00 |
08:54:09.88 |
+65:11:25.7 |
HIP 43910 |
25.07 |
| 2026-06-15 00:00 |
08:54:26.32 |
+65:10:16.7 |
HIP 43910 |
23.08 |
| 2026-06-15 12:00 |
08:54:42.85 |
+65:09:08.0 |
HIP 43910 |
21.11 |
| 2026-06-16 00:00 |
08:54:59.46 |
+65:07:59.6 |
HIP 43910 |
19.16 |
| 2026-06-16 12:00 |
08:55:16.16 |
+65:06:51.5 |
HIP 43910 |
17.24 |
| 2026-06-17 00:00 |
08:55:32.93 |
+65:05:43.7 |
HIP 43910 |
15.37 |
| 2026-06-17 12:00 |
08:55:49.78 |
+65:04:36.3 |
HIP 43910 |
13.56 |
| 2026-06-18 00:00 |
08:56:06.72 |
+65:03:29.2 |
HIP 43910 |
11.86 |
| 2026-06-18 12:00 |
08:56:23.73 |
+65:02:22.4 |
HIP 43910 |
10.32 |
| 2026-06-19 00:00 |
08:56:40.81 |
+65:01:15.9 |
HIP 43910 |
9.01 |
| 2026-06-19 12:00 |
08:56:57.98 |
+65:00:09.8 |
HIP 43910 |
8.06 |
| 2026-06-20 00:00 |
08:57:15.21 |
+64:59:04.0 |
HIP 43910 |
7.62 |
| 2026-06-20 12:00 |
08:57:32.53 |
+64:57:58.5 |
HIP 43910 |
7.77 |
| 2026-06-21 00:00 |
08:57:49.91 |
+64:56:53.4 |
HIP 43910 |
8.48 |
| 2026-06-21 12:00 |
08:58:07.37 |
+64:55:48.6 |
HIP 43910 |
9.64 |
| 2026-06-22 00:00 |
08:58:24.90 |
+64:54:44.2 |
HIP 43910 |
11.10 |