C/2024 S1 (ATLAS)
メタデータ
| 項目 | 値 |
|---|---|
| Designation | C/2024 S1 (ATLAS) |
| Type | C |
| Perihelion (tp_cal, UTC) | 2024-10-28T11:39:10.923840Z |
| Orbit solution date (soln_date, UTC) | 2025-09-09T12:42:42Z |
| Obs used | 289 |
| NEO | - |
| M1 | 15.300 |
| K1 | 4.500 |
| PC | - |
| Discovery observation (MPC, UTC) | 2024-09-27T14:47:46.464000Z |
| Discovery magnitude (MPC) | 15.30 o |
| Discovery observatory (MPC) | T05 · ATLAS-HKO, Haleakala |
オスキュレーティング軌道要素
| 項目 | 値 |
|---|---|
| Epoch (epoch_cal, TDB) | 2024-10-05.0000000 |
| e | 0.99991737 |
| q (au) | 0.007954 |
| a (au) | 96.258164 |
| i (deg) | 141.901469 |
| Ω (om, deg) | 347.150011 |
| ω (w, deg) | 69.163122 |
| M (ma, deg) | 359.975490 |
等級
散乱 + 全体線形
$$ M_a = (13.136 + 2.570\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
モデル定数
| 項目 | 値 |
|---|---|
| H0 | 13.136 |
| n | 2.570 |
| gf | 0.800 |
| gb | -0.500 |
| 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
残差 (区間線形)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| 開始日 (UTC) | 終了日 (UTC) | a | b |
|---|---|---|---|
| 2024-09-27 | 2024-10-10 | -1.0443 | +0.222 |
| 2024-10-10 | 2024-10-17 | +5.6025 | +1.583 |
| 2024-10-17 | 2024-10-20 | +8.6854 | +1.949 |
| 2024-10-20 | 2024-10-26 | -2.1925 | -1.747 |
| 2024-10-26 | 2024-10-27 | +0.2951 | -0.121 |
| 2024-10-27 | 2024-10-28 | -11.5966 | -13.835 |
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 | 06:34:39.91 | -08:30:50.1 | HIP 31371 | 5.66 |
| 2026-05-12 12:00 | 06:34:50.47 | -08:29:38.5 | HIP 31371 | 7.26 |
| 2026-05-13 00:00 | 06:35:01.10 | -08:28:27.9 | HIP 31371 | 9.48 |
| 2026-05-13 12:00 | 06:35:11.79 | -08:27:18.2 | HIP 31371 | 11.98 |
| 2026-05-14 00:00 | 06:35:22.54 | -08:26:09.4 | HIP 31371 | 14.63 |
| 2026-05-14 12:00 | 06:35:33.36 | -08:25:01.5 | HIP 31371 | 17.35 |
| 2026-05-15 00:00 | 06:35:44.24 | -08:23:54.5 | HIP 31371 | 20.13 |
| 2026-05-15 12:00 | 06:35:55.18 | -08:22:48.5 | HIP 31371 | 22.95 |
| 2026-05-16 00:00 | 06:36:06.18 | -08:21:43.3 | HIP 31656 | 22.55 |
| 2026-05-16 12:00 | 06:36:17.23 | -08:20:39.1 | HIP 31656 | 19.62 |
| 2026-05-17 00:00 | 06:36:28.35 | -08:19:35.7 | HIP 31656 | 16.67 |
| 2026-05-17 12:00 | 06:36:39.53 | -08:18:33.3 | HIP 31656 | 13.72 |
| 2026-05-18 00:00 | 06:36:50.76 | -08:17:31.8 | HIP 31656 | 10.76 |
| 2026-05-18 12:00 | 06:37:02.04 | -08:16:31.3 | HIP 31656 | 7.79 |
| 2026-05-19 00:00 | 06:37:13.39 | -08:15:31.6 | HIP 31656 | 4.82 |
| 2026-05-19 12:00 | 06:37:24.78 | -08:14:32.9 | HIP 31656 | 1.84 |
| 2026-05-20 00:00 | 06:37:36.23 | -08:13:35.1 | HIP 31656 | 1.18 |
| 2026-05-20 12:00 | 06:37:47.73 | -08:12:38.2 | HIP 31656 | 4.17 |
| 2026-05-21 00:00 | 06:37:59.28 | -08:11:42.2 | HIP 31656 | 7.17 |
| 2026-05-21 12:00 | 06:38:10.89 | -08:10:47.1 | HIP 31656 | 10.18 |
| 2026-05-22 00:00 | 06:38:22.54 | -08:09:53.0 | HIP 31656 | 13.20 |
| 2026-05-22 12:00 | 06:38:34.24 | -08:08:59.7 | HIP 31656 | 16.23 |
| 2026-05-23 00:00 | 06:38:45.99 | -08:08:07.4 | HIP 31656 | 19.26 |
| 2026-05-23 12:00 | 06:38:57.78 | -08:07:16.0 | HIP 31656 | 22.31 |
| 2026-05-24 00:00 | 06:39:09.62 | -08:06:25.5 | HIP 31656 | 25.35 |
| 2026-05-24 12:00 | 06:39:21.51 | -08:05:35.9 | HIP 31902 | 26.42 |
| 2026-05-25 00:00 | 06:39:33.44 | -08:04:47.3 | HIP 31902 | 26.13 |
| 2026-05-25 12:00 | 06:39:45.42 | -08:03:59.5 | HIP 31902 | 26.17 |
| 2026-05-26 00:00 | 06:39:57.44 | -08:03:12.7 | HIP 31902 | 26.56 |
| 2026-05-26 12:00 | 06:40:09.50 | -08:02:26.7 | HIP 31902 | 27.27 |
| 2026-05-27 00:00 | 06:40:21.60 | -08:01:41.7 | HIP 31902 | 28.29 |
| 2026-05-27 12:00 | 06:40:33.74 | -08:00:57.6 | HIP 31985 | 27.50 |
| 2026-05-28 00:00 | 06:40:45.92 | -08:00:14.4 | HIP 31985 | 26.18 |
| 2026-05-28 12:00 | 06:40:58.14 | -07:59:32.0 | HIP 31985 | 25.19 |
| 2026-05-29 00:00 | 06:41:10.40 | -07:58:50.6 | HIP 31985 | 24.58 |
| 2026-05-29 12:00 | 06:41:22.70 | -07:58:10.1 | HIP 31985 | 24.36 |
| 2026-05-30 00:00 | 06:41:35.03 | -07:57:30.5 | HIP 32176 | 23.15 |
| 2026-05-30 12:00 | 06:41:47.41 | -07:56:51.8 | HIP 32176 | 20.34 |
| 2026-05-31 00:00 | 06:41:59.81 | -07:56:14.0 | HIP 32176 | 17.64 |
| 2026-05-31 12:00 | 06:42:12.25 | -07:55:37.1 | HIP 32176 | 15.08 |
| 2026-06-01 00:00 | 06:42:24.73 | -07:55:01.1 | HIP 32176 | 12.77 |
| 2026-06-01 12:00 | 06:42:37.24 | -07:54:26.0 | HIP 32176 | 10.88 |
| 2026-06-02 00:00 | 06:42:49.78 | -07:53:51.8 | HIP 32176 | 9.64 |