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 |
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) |
|---|---|---|---|---|
| 2026-09-20 00:00 | 13:20:43.65 | +62:22:38.3 | HIP 65068 | 12.23 |
| 2026-09-20 12:00 | 13:20:53.28 | +62:22:02.7 | HIP 65068 | 13.13 |
| 2026-09-21 00:00 | 13:21:02.93 | +62:21:27.7 | HIP 65068 | 14.08 |
| 2026-09-21 12:00 | 13:21:12.61 | +62:20:53.1 | HIP 65068 | 15.07 |
| 2026-09-22 00:00 | 13:21:22.32 | +62:20:19.1 | HIP 65068 | 16.09 |
| 2026-09-22 12:00 | 13:21:32.06 | +62:19:45.5 | HIP 65068 | 17.14 |
| 2026-09-23 00:00 | 13:21:41.83 | +62:19:12.5 | HIP 65068 | 18.21 |
| 2026-09-23 12:00 | 13:21:51.62 | +62:18:39.9 | HIP 65068 | 19.29 |
| 2026-09-24 00:00 | 13:22:01.44 | +62:18:07.9 | HIP 65068 | 20.40 |
| 2026-09-24 12:00 | 13:22:11.29 | +62:17:36.4 | HIP 65068 | 21.51 |
| 2026-09-25 00:00 | 13:22:21.15 | +62:17:05.4 | HIP 65110 | 22.34 |
| 2026-09-25 12:00 | 13:22:31.05 | +62:16:34.9 | HIP 65110 | 22.58 |
| 2026-09-26 00:00 | 13:22:40.97 | +62:16:04.9 | HIP 65110 | 22.91 |
| 2026-09-26 12:00 | 13:22:50.91 | +62:15:35.4 | HIP 65110 | 23.30 |
| 2026-09-27 00:00 | 13:23:00.87 | +62:15:06.5 | HIP 65110 | 23.76 |
| 2026-09-27 12:00 | 13:23:10.86 | +62:14:38.0 | HIP 65110 | 24.29 |
| 2026-09-28 00:00 | 13:23:20.87 | +62:14:10.1 | HIP 65110 | 24.88 |
| 2026-09-28 12:00 | 13:23:30.90 | +62:13:42.7 | HIP 65110 | 25.52 |
| 2026-09-29 00:00 | 13:23:40.95 | +62:13:15.9 | HIP 65110 | 26.22 |
| 2026-09-29 12:00 | 13:23:51.03 | +62:12:49.5 | HIP 65110 | 26.96 |
| 2026-09-30 00:00 | 13:24:01.12 | +62:12:23.7 | HIP 65561 | 26.94 |
| 2026-09-30 12:00 | 13:24:11.23 | +62:11:58.5 | HIP 65561 | 25.86 |
| 2026-10-01 00:00 | 13:24:21.37 | +62:11:33.7 | HIP 65561 | 24.79 |
| 2026-10-01 12:00 | 13:24:31.52 | +62:11:09.5 | HIP 65561 | 23.75 |
| 2026-10-02 00:00 | 13:24:41.69 | +62:10:45.8 | HIP 65561 | 22.74 |
| 2026-10-02 12:00 | 13:24:51.87 | +62:10:22.7 | HIP 65561 | 21.76 |
| 2026-10-03 00:00 | 13:25:02.08 | +62:10:00.1 | HIP 65561 | 20.81 |
| 2026-10-03 12:00 | 13:25:12.30 | +62:09:38.1 | HIP 65561 | 19.91 |
| 2026-10-04 00:00 | 13:25:22.54 | +62:09:16.6 | HIP 65561 | 19.05 |
| 2026-10-04 12:00 | 13:25:32.79 | +62:08:55.6 | HIP 65561 | 18.24 |
| 2026-10-05 00:00 | 13:25:43.06 | +62:08:35.2 | HIP 65561 | 17.50 |
| 2026-10-05 12:00 | 13:25:53.34 | +62:08:15.4 | HIP 65561 | 16.83 |
| 2026-10-06 00:00 | 13:26:03.64 | +62:07:56.1 | HIP 65561 | 16.23 |
| 2026-10-06 12:00 | 13:26:13.95 | +62:07:37.4 | HIP 65561 | 15.72 |
| 2026-10-07 00:00 | 13:26:24.27 | +62:07:19.2 | HIP 65561 | 15.30 |
| 2026-10-07 12:00 | 13:26:34.61 | +62:07:01.6 | HIP 65561 | 14.99 |
| 2026-10-08 00:00 | 13:26:44.96 | +62:06:44.5 | HIP 65561 | 14.78 |
| 2026-10-08 12:00 | 13:26:55.31 | +62:06:28.1 | HIP 65561 | 14.69 |
| 2026-10-09 00:00 | 13:27:05.68 | +62:06:12.1 | HIP 65561 | 14.71 |
| 2026-10-09 12:00 | 13:27:16.06 | +62:05:56.8 | HIP 65561 | 14.85 |
| 2026-10-10 00:00 | 13:27:26.45 | +62:05:42.0 | HIP 65561 | 15.09 |
| 2026-10-10 12:00 | 13:27:36.85 | +62:05:27.8 | HIP 65561 | 15.45 |
| 2026-10-11 00:00 | 13:27:47.25 | +62:05:14.2 | HIP 65561 | 15.90 |