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 |
-0.7569 |
+0.403 |
| 2018-02-06 |
2018-03-16 |
-3.9243 |
+1.642 |
| 2018-03-16 |
2018-04-07 |
-11.8310 |
+4.241 |
| 2018-04-07 |
2018-07-18 |
+4.1328 |
-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) |
| 2026-06-01 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 |
| 2026-06-02 12:00 |
16:01:53.68 |
+26:35:01.2 |
HIP 78572 |
10.15 |
| 2026-06-03 00:00 |
16:01:47.73 |
+26:35:06.8 |
HIP 78572 |
11.45 |
| 2026-06-03 12:00 |
16:01:41.79 |
+26:35:11.8 |
HIP 78497 |
11.31 |
| 2026-06-04 00:00 |
16:01:35.86 |
+26:35:16.2 |
HIP 78497 |
11.11 |
| 2026-06-04 12:00 |
16:01:29.94 |
+26:35:20.1 |
HIP 78497 |
11.06 |
| 2026-06-05 00:00 |
16:01:24.03 |
+26:35:23.5 |
HIP 78497 |
11.16 |
| 2026-06-05 12:00 |
16:01:18.13 |
+26:35:26.3 |
HIP 78497 |
11.41 |
| 2026-06-06 00:00 |
16:01:12.25 |
+26:35:28.5 |
HIP 78497 |
11.78 |
| 2026-06-06 12:00 |
16:01:06.39 |
+26:35:30.2 |
HIP 78497 |
12.28 |
| 2026-06-07 00:00 |
16:01:00.53 |
+26:35:31.4 |
HIP 78497 |
12.88 |
| 2026-06-07 12:00 |
16:00:54.70 |
+26:35:32.0 |
HIP 78497 |
13.58 |
| 2026-06-08 00:00 |
16:00:48.87 |
+26:35:32.1 |
HIP 78497 |
14.35 |
| 2026-06-08 12:00 |
16:00:43.07 |
+26:35:31.6 |
HIP 78497 |
15.18 |
| 2026-06-09 00:00 |
16:00:37.28 |
+26:35:30.6 |
HIP 78497 |
16.07 |
| 2026-06-09 12:00 |
16:00:31.50 |
+26:35:29.0 |
HIP 78497 |
17.00 |
| 2026-06-10 00:00 |
16:00:25.75 |
+26:35:26.9 |
HIP 78497 |
17.96 |
| 2026-06-10 12:00 |
16:00:20.01 |
+26:35:24.3 |
HIP 78497 |
18.96 |
| 2026-06-11 00:00 |
16:00:14.29 |
+26:35:21.1 |
HIP 78497 |
19.98 |
| 2026-06-11 12:00 |
16:00:08.58 |
+26:35:17.4 |
HIP 78497 |
21.02 |
| 2026-06-12 00:00 |
16:00:02.90 |
+26:35:13.1 |
HIP 78497 |
22.08 |
| 2026-06-12 12:00 |
15:59:57.24 |
+26:35:08.3 |
HIP 78497 |
23.15 |
| 2026-06-13 00:00 |
15:59:51.59 |
+26:35:03.0 |
HIP 78497 |
24.23 |
| 2026-06-13 12:00 |
15:59:45.97 |
+26:34:57.1 |
HIP 78234 |
23.41 |
| 2026-06-14 00:00 |
15:59:40.37 |
+26:34:50.7 |
HIP 78234 |
22.60 |
| 2026-06-14 12:00 |
15:59:34.79 |
+26:34:43.7 |
HIP 78234 |
21.85 |
| 2026-06-15 00:00 |
15:59:29.23 |
+26:34:36.2 |
HIP 78234 |
21.15 |
| 2026-06-15 12:00 |
15:59:23.69 |
+26:34:28.2 |
HIP 78234 |
20.51 |
| 2026-06-16 00:00 |
15:59:18.18 |
+26:34:19.7 |
HIP 78234 |
19.95 |
| 2026-06-16 12:00 |
15:59:12.69 |
+26:34:10.6 |
HIP 78234 |
19.45 |
| 2026-06-17 00:00 |
15:59:07.22 |
+26:34:01.0 |
HIP 78234 |
19.03 |
| 2026-06-17 12:00 |
15:59:01.78 |
+26:33:50.9 |
HIP 78234 |
18.70 |
| 2026-06-18 00:00 |
15:58:56.36 |
+26:33:40.3 |
HIP 78234 |
18.45 |
| 2026-06-18 12:00 |
15:58:50.97 |
+26:33:29.1 |
HIP 78234 |
18.29 |
| 2026-06-19 00:00 |
15:58:45.60 |
+26:33:17.5 |
HIP 78234 |
18.22 |
| 2026-06-19 12:00 |
15:58:40.26 |
+26:33:05.3 |
HIP 78234 |
18.23 |
| 2026-06-20 00:00 |
15:58:34.95 |
+26:32:52.6 |
HIP 78234 |
18.34 |
| 2026-06-20 12:00 |
15:58:29.66 |
+26:32:39.4 |
HIP 78234 |
18.53 |
| 2026-06-21 00:00 |
15:58:24.40 |
+26:32:25.7 |
HIP 78206 |
18.19 |
| 2026-06-21 12:00 |
15:58:19.17 |
+26:32:11.4 |
HIP 78206 |
17.79 |
| 2026-06-22 00:00 |
15:58:13.97 |
+26:31:56.7 |
HIP 78206 |
17.46 |