C/2025 L1 (ATLAS)
メタデータ
| 項目 | 値 |
|---|---|
| Designation | C/2025 L1 (ATLAS) |
| Type | C |
| Perihelion (tp_cal, UTC) | 2026-01-12T17:39:04.167360Z |
| Orbit solution date (soln_date, UTC) | 2026-04-21T14:52:47Z |
| Obs used | 130 |
| NEO | - |
| M1 | 14.300 |
| K1 | 4.500 |
| PC | - |
| Discovery observation (MPC, UTC) | 2025-06-06T09:16:16.579200Z |
| Discovery magnitude (MPC) | 18.22 c |
| 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) | 2025-10-19.0000000 |
| e | 1.00142840 |
| q (au) | 1.679641 |
| a (au) | -1175.889046 |
| i (deg) | 114.137040 |
| Ω (om, deg) | 208.109033 |
| ω (w, deg) | 341.250672 |
| M (ma, deg) | -0.002096 |
等級
散乱 + 全体線形
$$ M_a = (15.967 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
モデル定数
| 項目 | 値 |
|---|---|
| H0 | 15.967 |
| n | 2.000 |
| gf | 1.000 |
| gb | -0.814 |
| k | 0.800 |
| 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 |
|---|---|---|---|
| 2024-10-01 | 2026-01-02 | +6.3680 | -3.217 |
| 2026-01-13 | 2026-04-15 | +26.7848 | -6.530 |
log10 r = log10(太陽距離/AU)、Δ = 地球距離(AU)
ファインディングチャート
天体暦
| Date/Time (UTC) | RA (J2000) | Dec (J2000) | Nearest HIP | Dist from HIP (arcmin) |
|---|---|---|---|---|
| 2026-05-12 00:00 | 12:10:29.10 | +53:11:05.3 | HIP 59258 | 16.24 |
| 2026-05-12 12:00 | 12:09:19.83 | +53:12:56.6 | HIP 59258 | 10.74 |
| 2026-05-13 00:00 | 12:08:11.89 | +53:14:39.1 | HIP 59258 | 13.66 |
| 2026-05-13 12:00 | 12:07:05.25 | +53:16:12.9 | HIP 58995 | 17.49 |
| 2026-05-14 00:00 | 12:05:59.92 | +53:17:38.3 | HIP 58995 | 11.59 |
| 2026-05-14 12:00 | 12:04:55.88 | +53:18:55.7 | HIP 58995 | 12.51 |
| 2026-05-15 00:00 | 12:03:53.13 | +53:20:05.3 | HIP 58995 | 18.97 |
| 2026-05-15 12:00 | 12:02:51.65 | +53:21:07.3 | HIP 58995 | 27.07 |
| 2026-05-16 00:00 | 12:01:51.44 | +53:22:02.0 | HIP 58496 | 18.39 |
| 2026-05-16 12:00 | 12:00:52.49 | +53:22:49.6 | HIP 58496 | 9.56 |
| 2026-05-17 00:00 | 11:59:54.79 | +53:23:30.4 | HIP 58496 | 0.97 |
| 2026-05-17 12:00 | 11:58:58.32 | +53:24:04.7 | HIP 58496 | 7.52 |
| 2026-05-18 00:00 | 11:58:03.07 | +53:24:32.6 | HIP 58318 | 9.92 |
| 2026-05-18 12:00 | 11:57:09.04 | +53:24:54.4 | HIP 58318 | 8.97 |
| 2026-05-19 00:00 | 11:56:16.22 | +53:25:10.2 | HIP 58318 | 13.77 |
| 2026-05-19 12:00 | 11:55:24.58 | +53:25:20.3 | HIP 58318 | 20.43 |
| 2026-05-20 00:00 | 11:54:34.12 | +53:25:25.0 | HIP 58001 | 17.55 |
| 2026-05-20 12:00 | 11:53:44.82 | +53:25:24.4 | HIP 58001 | 16.29 |
| 2026-05-21 00:00 | 11:52:56.68 | +53:25:18.6 | HIP 58001 | 18.17 |
| 2026-05-21 12:00 | 11:52:09.68 | +53:25:07.9 | HIP 58001 | 22.24 |
| 2026-05-22 00:00 | 11:51:23.80 | +53:24:52.5 | HIP 57706 | 26.56 |
| 2026-05-22 12:00 | 11:50:39.03 | +53:24:32.6 | HIP 57706 | 24.65 |
| 2026-05-23 00:00 | 11:49:55.37 | +53:24:08.2 | HIP 57706 | 24.52 |
| 2026-05-23 12:00 | 11:49:12.79 | +53:23:39.6 | HIP 57487 | 20.76 |
| 2026-05-24 00:00 | 11:48:31.29 | +53:23:07.0 | HIP 57487 | 14.78 |
| 2026-05-24 12:00 | 11:47:50.84 | +53:22:30.4 | HIP 57487 | 9.21 |
| 2026-05-25 00:00 | 11:47:11.44 | +53:21:50.1 | HIP 57487 | 4.98 |
| 2026-05-25 12:00 | 11:46:33.07 | +53:21:06.1 | HIP 57483 | 5.59 |
| 2026-05-26 00:00 | 11:45:55.72 | +53:20:18.7 | HIP 57483 | 10.05 |
| 2026-05-26 12:00 | 11:45:19.38 | +53:19:27.9 | HIP 57483 | 15.16 |
| 2026-05-27 00:00 | 11:44:44.03 | +53:18:33.9 | HIP 57115 | 19.77 |
| 2026-05-27 12:00 | 11:44:09.66 | +53:17:36.9 | HIP 57115 | 14.68 |
| 2026-05-28 00:00 | 11:43:36.26 | +53:16:36.8 | HIP 57115 | 9.87 |
| 2026-05-28 12:00 | 11:43:03.81 | +53:15:33.9 | HIP 57115 | 5.74 |
| 2026-05-29 00:00 | 11:42:32.30 | +53:14:28.3 | HIP 57115 | 4.25 |
| 2026-05-29 12:00 | 11:42:01.72 | +53:13:20.0 | HIP 57115 | 7.01 |
| 2026-05-30 00:00 | 11:41:32.05 | +53:12:09.2 | HIP 57115 | 11.08 |
| 2026-05-30 12:00 | 11:41:03.29 | +53:10:56.0 | HIP 57115 | 15.35 |
| 2026-05-31 00:00 | 11:40:35.41 | +53:09:40.4 | HIP 57023 | 19.53 |
| 2026-05-31 12:00 | 11:40:08.42 | +53:08:22.7 | HIP 57023 | 20.48 |
| 2026-06-01 00:00 | 11:39:42.29 | +53:07:02.7 | HIP 57023 | 22.11 |
| 2026-06-01 12:00 | 11:39:17.01 | +53:05:40.8 | HIP 57023 | 24.22 |
| 2026-06-02 00:00 | 11:38:52.57 | +53:04:16.9 | HIP 57023 | 26.65 |