C/2017 S3 (PANSTARRS)
メタデータ
| 項目 | 値 |
|---|---|
| Designation | C/2017 S3 (PANSTARRS) |
| Type | C |
| Perihelion (tp_cal, UTC) | 2018-08-15T22:45:39.003840Z |
| Orbit solution date (soln_date, UTC) | 2021-04-16T12:04:16Z |
| Obs used | 986 |
| NEO | - |
| M1 | 13.200 |
| K1 | 8.250 |
| PC | - |
オスキュレーティング軌道要素
| 項目 | 値 |
|---|---|
| Epoch (epoch_cal, TDB) | 2018-04-27.0000000 |
| e | 1.00007796 |
| q (au) | 0.208446 |
| a (au) | -2673.667700 |
| i (deg) | 99.038653 |
| Ω (om, deg) | 171.042492 |
| ω (w, deg) | 255.892231 |
| M (ma, deg) | -0.000791 |
等級
散乱 + 全体線形
$$ M_a = (9.352 + 4.553\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
モデル定数
| 項目 | 値 |
|---|---|
| H0 | 9.352 |
| n | 4.553 |
| gf | 0.800 |
| gb | -0.500 |
| k | 1.000 |
| δ90 | 1.000 |
| 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 |
|---|---|---|---|
| 2017-08-17 | 2018-06-23 | -3.2015 | +2.122 |
| 2018-06-23 | 2018-07-06 | +31.4848 | -3.170 |
| 2018-07-06 | 2018-07-15 | -12.2246 | +0.039 |
| 2018-07-15 | 2018-07-21 | +4.0302 | -0.473 |
| 2018-07-21 | 2018-08-03 | -20.0442 | -1.795 |
| 2018-10-16 | 2018-11-16 | -10.4094 | -2.038 |
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) |
|---|---|---|---|---|
| 2026-02-03 00:00 | 13:50:37.74 | +64:40:56.7 | HIP 67627 | 5.70 |
| 2026-02-03 12:00 | 13:50:34.82 | +64:42:21.4 | HIP 67627 | 5.56 |
| 2026-02-04 00:00 | 13:50:31.79 | +64:43:46.0 | HIP 67627 | 5.79 |
| 2026-02-04 12:00 | 13:50:28.64 | +64:45:10.4 | HIP 67627 | 6.37 |
| 2026-02-05 00:00 | 13:50:25.39 | +64:46:34.6 | HIP 67627 | 7.20 |
| 2026-02-05 12:00 | 13:50:22.02 | +64:47:58.7 | HIP 67627 | 8.21 |
| 2026-02-06 00:00 | 13:50:18.55 | +64:49:22.6 | HIP 67627 | 9.34 |
| 2026-02-06 12:00 | 13:50:14.96 | +64:50:46.4 | HIP 67627 | 10.56 |
| 2026-02-07 00:00 | 13:50:11.27 | +64:52:10.0 | HIP 67627 | 11.84 |
| 2026-02-07 12:00 | 13:50:07.46 | +64:53:33.4 | HIP 67627 | 13.15 |
| 2026-02-08 00:00 | 13:50:03.54 | +64:54:56.6 | HIP 67627 | 14.50 |
| 2026-02-08 12:00 | 13:49:59.52 | +64:56:19.6 | HIP 67627 | 15.86 |
| 2026-02-09 00:00 | 13:49:55.38 | +64:57:42.4 | HIP 67627 | 17.25 |
| 2026-02-09 12:00 | 13:49:51.13 | +64:59:05.0 | HIP 67376 | 15.96 |
| 2026-02-10 00:00 | 13:49:46.77 | +65:00:27.4 | HIP 67376 | 14.54 |
| 2026-02-10 12:00 | 13:49:42.30 | +65:01:49.6 | HIP 67376 | 13.14 |
| 2026-02-11 00:00 | 13:49:37.72 | +65:03:11.5 | HIP 67376 | 11.74 |
| 2026-02-11 12:00 | 13:49:33.04 | +65:04:33.2 | HIP 67376 | 10.35 |
| 2026-02-12 00:00 | 13:49:28.24 | +65:05:54.6 | HIP 67376 | 8.97 |
| 2026-02-12 12:00 | 13:49:23.33 | +65:07:15.8 | HIP 67376 | 7.62 |
| 2026-02-13 00:00 | 13:49:18.31 | +65:08:36.7 | HIP 67376 | 6.30 |
| 2026-02-13 12:00 | 13:49:13.19 | +65:09:57.4 | HIP 67376 | 5.06 |
| 2026-02-14 00:00 | 13:49:07.95 | +65:11:17.8 | HIP 67376 | 3.94 |
| 2026-02-14 12:00 | 13:49:02.61 | +65:12:37.9 | HIP 67376 | 3.09 |
| 2026-02-15 00:00 | 13:48:57.16 | +65:13:57.7 | HIP 67376 | 2.79 |
| 2026-02-15 12:00 | 13:48:51.60 | +65:15:17.2 | HIP 67376 | 3.18 |
| 2026-02-16 00:00 | 13:48:45.93 | +65:16:36.4 | HIP 67376 | 4.07 |
| 2026-02-16 12:00 | 13:48:40.16 | +65:17:55.2 | HIP 67376 | 5.21 |
| 2026-02-17 00:00 | 13:48:34.28 | +65:19:13.8 | HIP 67376 | 6.47 |
| 2026-02-17 12:00 | 13:48:28.29 | +65:20:32.0 | HIP 67376 | 7.79 |
| 2026-02-18 00:00 | 13:48:22.19 | +65:21:49.9 | HIP 67376 | 9.14 |
| 2026-02-18 12:00 | 13:48:15.99 | +65:23:07.5 | HIP 67376 | 10.51 |
| 2026-02-19 00:00 | 13:48:09.68 | +65:24:24.7 | HIP 67376 | 11.90 |
| 2026-02-19 12:00 | 13:48:03.27 | +65:25:41.6 | HIP 67376 | 13.30 |
| 2026-02-20 00:00 | 13:47:56.75 | +65:26:58.0 | HIP 67376 | 14.70 |
| 2026-02-20 12:00 | 13:47:50.13 | +65:28:14.2 | HIP 67376 | 16.11 |
| 2026-02-21 00:00 | 13:47:43.41 | +65:29:29.9 | HIP 67376 | 17.52 |
| 2026-02-21 12:00 | 13:47:36.58 | +65:30:45.3 | HIP 67376 | 18.93 |
| 2026-02-22 00:00 | 13:47:29.65 | +65:32:00.2 | HIP 67141 | 20.07 |
| 2026-02-22 12:00 | 13:47:22.62 | +65:33:14.8 | HIP 67141 | 18.63 |
| 2026-02-23 00:00 | 13:47:15.48 | +65:34:28.9 | HIP 67141 | 17.20 |
| 2026-02-23 12:00 | 13:47:08.25 | +65:35:42.7 | HIP 67141 | 15.77 |
| 2026-02-24 00:00 | 13:47:00.91 | +65:36:56.0 | HIP 67141 | 14.34 |