メタデータ
| 項目 |
値 |
| Designation |
C/2017 T3 (ATLAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2018-07-19T03:33:40.913280Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:37Z |
| Obs used |
542 |
| NEO |
- |
| M1 |
11.100 |
| K1 |
7.250 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2017-12-26.0000000 |
| e |
0.99938609 |
| q (au) |
0.825222 |
| a (au) |
1344.198875 |
| i (deg) |
88.107202 |
| Ω (om, deg) |
230.086754 |
| ω (w, deg) |
246.893600 |
| M (ma, deg) |
359.995897 |
等級
散乱 + 全体線形
$$
M_a = (8.810 + 4.560\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
8.810 |
| n |
4.560 |
| gf |
0.999 |
| gb |
-1.000 |
| k |
0.996 |
| 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 |
| 2017-09-11 |
2018-02-06 |
-0.7566 |
+0.403 |
| 2018-02-06 |
2018-03-16 |
-3.9246 |
+1.642 |
| 2018-03-16 |
2018-04-07 |
-11.8318 |
+4.242 |
| 2018-04-07 |
2018-07-18 |
+4.1330 |
-0.327 |
| 2018-07-19 |
2019-02-28 |
+4.6236 |
+0.173 |
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) |
| 2026-05-12 00:00 |
16:06:13.33 |
+26:22:24.0 |
HIP 78787 |
29.81 |
| 2026-05-12 12:00 |
16:06:07.37 |
+26:22:53.0 |
HIP 78787 |
28.71 |
| 2026-05-13 00:00 |
16:06:01.39 |
+26:23:21.4 |
HIP 78787 |
27.65 |
| 2026-05-13 12:00 |
16:05:55.41 |
+26:23:49.4 |
HIP 78787 |
26.64 |
| 2026-05-14 00:00 |
16:05:49.41 |
+26:24:16.8 |
HIP 78787 |
25.66 |
| 2026-05-14 12:00 |
16:05:43.41 |
+26:24:43.6 |
HIP 78787 |
24.74 |
| 2026-05-15 00:00 |
16:05:37.39 |
+26:25:10.0 |
HIP 78787 |
23.87 |
| 2026-05-15 12:00 |
16:05:31.37 |
+26:25:35.8 |
HIP 78787 |
23.06 |
| 2026-05-16 00:00 |
16:05:25.34 |
+26:26:01.1 |
HIP 78787 |
22.33 |
| 2026-05-16 12:00 |
16:05:19.31 |
+26:26:25.8 |
HIP 78787 |
21.67 |
| 2026-05-17 00:00 |
16:05:13.26 |
+26:26:50.0 |
HIP 78787 |
21.09 |
| 2026-05-17 12:00 |
16:05:07.22 |
+26:27:13.7 |
HIP 78787 |
20.60 |
| 2026-05-18 00:00 |
16:05:01.16 |
+26:27:36.8 |
HIP 78787 |
20.21 |
| 2026-05-18 12:00 |
16:04:55.10 |
+26:27:59.3 |
HIP 78787 |
19.91 |
| 2026-05-19 00:00 |
16:04:49.04 |
+26:28:21.4 |
HIP 78787 |
19.73 |
| 2026-05-19 12:00 |
16:04:42.97 |
+26:28:42.8 |
HIP 78787 |
19.65 |
| 2026-05-20 00:00 |
16:04:36.90 |
+26:29:03.8 |
HIP 78787 |
19.68 |
| 2026-05-20 12:00 |
16:04:30.83 |
+26:29:24.2 |
HIP 78787 |
19.82 |
| 2026-05-21 00:00 |
16:04:24.75 |
+26:29:44.0 |
HIP 78787 |
20.06 |
| 2026-05-21 12:00 |
16:04:18.68 |
+26:30:03.3 |
HIP 78787 |
20.40 |
| 2026-05-22 00:00 |
16:04:12.60 |
+26:30:22.0 |
HIP 78787 |
20.84 |
| 2026-05-22 12:00 |
16:04:06.52 |
+26:30:40.2 |
HIP 78572 |
20.61 |
| 2026-05-23 00:00 |
16:04:00.44 |
+26:30:57.9 |
HIP 78572 |
19.22 |
| 2026-05-23 12:00 |
16:03:54.37 |
+26:31:14.9 |
HIP 78572 |
17.84 |
| 2026-05-24 00:00 |
16:03:48.29 |
+26:31:31.5 |
HIP 78572 |
16.47 |
| 2026-05-24 12:00 |
16:03:42.22 |
+26:31:47.5 |
HIP 78572 |
15.09 |
| 2026-05-25 00:00 |
16:03:36.14 |
+26:32:02.9 |
HIP 78572 |
13.73 |
| 2026-05-25 12:00 |
16:03:30.07 |
+26:32:17.8 |
HIP 78572 |
12.37 |
| 2026-05-26 00:00 |
16:03:24.01 |
+26:32:32.2 |
HIP 78572 |
11.02 |
| 2026-05-26 12:00 |
16:03:17.94 |
+26:32:45.9 |
HIP 78572 |
9.68 |
| 2026-05-27 00:00 |
16:03:11.88 |
+26:32:59.2 |
HIP 78572 |
8.36 |
| 2026-05-27 12:00 |
16:03:05.83 |
+26:33:11.9 |
HIP 78572 |
7.07 |
| 2026-05-28 00:00 |
16:02:59.78 |
+26:33:24.0 |
HIP 78572 |
5.82 |
| 2026-05-28 12:00 |
16:02:53.73 |
+26:33:35.6 |
HIP 78572 |
4.64 |
| 2026-05-29 00:00 |
16:02:47.69 |
+26:33:46.6 |
HIP 78572 |
3.61 |
| 2026-05-29 12:00 |
16:02:41.66 |
+26:33:57.1 |
HIP 78572 |
2.87 |
| 2026-05-30 00:00 |
16:02:35.63 |
+26:34:07.1 |
HIP 78572 |
2.69 |
| 2026-05-30 12:00 |
16:02:29.61 |
+26:34:16.5 |
HIP 78572 |
3.15 |
| 2026-05-31 00:00 |
16:02:23.60 |
+26:34:25.3 |
HIP 78572 |
4.04 |
| 2026-05-31 12:00 |
16:02:17.60 |
+26:34:33.6 |
HIP 78572 |
5.14 |
| 2026-06-01 00:00 |
16:02:11.61 |
+26:34:41.3 |
HIP 78572 |
6.34 |
| 2026-06-01 12:00 |
16:02:05.62 |
+26:34:48.5 |
HIP 78572 |
7.58 |
| 2026-06-02 00:00 |
16:01:59.65 |
+26:34:55.1 |
HIP 78572 |
8.86 |