メタデータ
| 項目 |
値 |
| Designation |
C/2024 X2 (ATLAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2025-07-07T21:16:49.195200Z |
| Orbit solution date (soln_date, UTC) |
2026-07-06T12:12:24Z |
| Obs used |
505 |
| NEO |
- |
| M1 |
6.900 |
| K1 |
14.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2024-12-12T07:14:54.009600Z |
| Discovery magnitude (MPC) |
18.84 o |
| Discovery observatory (MPC) |
W68 · ATLAS Chile, Rio Hurtado |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2025-07-07.0000000 |
| e |
0.92731632 |
| q (au) |
3.676302 |
| a (au) |
50.579478 |
| i (deg) |
109.221306 |
| Ω (om, deg) |
122.522615 |
| ω (w, deg) |
315.782732 |
| M (ma, deg) |
359.997571 |
等級
散乱 + 全体線形
$$
M_a = (5.562 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
5.562 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.998 |
| 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) |
| 2026-07-29 00:00 |
08:14:25.57 |
+33:29:02.6 |
HIP 40349 |
4.56 |
| 2026-07-29 12:00 |
08:14:47.06 |
+33:30:52.4 |
HIP 40349 |
6.67 |
| 2026-07-30 00:00 |
08:15:08.53 |
+33:32:42.5 |
HIP 40349 |
10.72 |
| 2026-07-30 12:00 |
08:15:30.00 |
+33:34:32.9 |
HIP 40349 |
15.23 |
| 2026-07-31 00:00 |
08:15:51.46 |
+33:36:23.7 |
HIP 40349 |
19.89 |
| 2026-07-31 12:00 |
08:16:12.91 |
+33:38:14.9 |
HIP 40349 |
24.62 |
| 2026-08-01 00:00 |
08:16:34.34 |
+33:40:06.4 |
HIP 40349 |
29.37 |
| 2026-08-01 12:00 |
08:16:55.77 |
+33:41:58.4 |
HIP 40716 |
31.05 |
| 2026-08-02 00:00 |
08:17:17.17 |
+33:43:50.7 |
HIP 40716 |
29.53 |
| 2026-08-02 12:00 |
08:17:38.57 |
+33:45:43.4 |
HIP 40716 |
28.76 |
| 2026-08-03 00:00 |
08:17:59.95 |
+33:47:36.6 |
HIP 40716 |
28.81 |
| 2026-08-03 12:00 |
08:18:21.31 |
+33:49:30.2 |
HIP 40716 |
29.66 |
| 2026-08-04 00:00 |
08:18:42.65 |
+33:51:24.1 |
HIP 40716 |
31.25 |
| 2026-08-04 12:00 |
08:19:03.98 |
+33:53:18.6 |
HIP 40966 |
31.89 |
| 2026-08-05 00:00 |
08:19:25.29 |
+33:55:13.4 |
HIP 40966 |
27.35 |
| 2026-08-05 12:00 |
08:19:46.59 |
+33:57:08.7 |
HIP 40966 |
22.93 |
| 2026-08-06 00:00 |
08:20:07.86 |
+33:59:04.5 |
HIP 40966 |
18.72 |
| 2026-08-06 12:00 |
08:20:29.11 |
+34:01:00.8 |
HIP 40966 |
14.88 |
| 2026-08-07 00:00 |
08:20:50.34 |
+34:02:57.5 |
HIP 40966 |
11.80 |
| 2026-08-07 12:00 |
08:21:11.55 |
+34:04:54.7 |
HIP 40966 |
10.18 |
| 2026-08-08 00:00 |
08:21:32.73 |
+34:06:52.4 |
HIP 40966 |
10.70 |
| 2026-08-08 12:00 |
08:21:53.89 |
+34:08:50.5 |
HIP 40942 |
11.93 |
| 2026-08-09 00:00 |
08:22:15.02 |
+34:10:49.2 |
HIP 40942 |
13.65 |
| 2026-08-09 12:00 |
08:22:36.13 |
+34:12:48.5 |
HIP 40942 |
16.61 |
| 2026-08-10 00:00 |
08:22:57.22 |
+34:14:48.2 |
HIP 41202 |
19.84 |
| 2026-08-10 12:00 |
08:23:18.27 |
+34:16:48.5 |
HIP 41202 |
16.53 |
| 2026-08-11 00:00 |
08:23:39.29 |
+34:18:49.3 |
HIP 41202 |
14.11 |
| 2026-08-11 12:00 |
08:24:00.29 |
+34:20:50.7 |
HIP 41202 |
13.08 |
| 2026-08-12 00:00 |
08:24:21.25 |
+34:22:52.6 |
HIP 41202 |
13.76 |
| 2026-08-12 12:00 |
08:24:42.18 |
+34:24:55.2 |
HIP 41202 |
15.92 |
| 2026-08-13 00:00 |
08:25:03.08 |
+34:26:58.3 |
HIP 41202 |
19.07 |
| 2026-08-13 12:00 |
08:25:23.95 |
+34:29:01.9 |
HIP 41356 |
19.50 |
| 2026-08-14 00:00 |
08:25:44.78 |
+34:31:06.2 |
HIP 41356 |
19.57 |
| 2026-08-14 12:00 |
08:26:05.57 |
+34:33:11.1 |
HIP 41356 |
20.78 |
| 2026-08-15 00:00 |
08:26:26.33 |
+34:35:16.6 |
HIP 41356 |
22.94 |
| 2026-08-15 12:00 |
08:26:47.05 |
+34:37:22.8 |
HIP 41356 |
25.82 |
| 2026-08-16 00:00 |
08:27:07.73 |
+34:39:29.5 |
HIP 41554 |
26.49 |
| 2026-08-16 12:00 |
08:27:28.37 |
+34:41:36.9 |
HIP 41554 |
22.41 |
| 2026-08-17 00:00 |
08:27:48.97 |
+34:43:45.0 |
HIP 41554 |
18.63 |
| 2026-08-17 12:00 |
08:28:09.53 |
+34:45:53.7 |
HIP 41554 |
15.38 |
| 2026-08-18 00:00 |
08:28:30.04 |
+34:48:03.1 |
HIP 41554 |
13.07 |
| 2026-08-18 12:00 |
08:28:50.52 |
+34:50:13.1 |
HIP 41554 |
12.21 |
| 2026-08-19 00:00 |
08:29:10.94 |
+34:52:23.9 |
HIP 41669 |
9.11 |