メタデータ
| 項目 |
値 |
| Designation |
C/2013 W2 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2015-01-05T06:10:39.014400Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:43Z |
| Obs used |
179 |
| NEO |
- |
| M1 |
6.900 |
| K1 |
13.750 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2015-01-20.0000000 |
| e |
0.57470690 |
| q (au) |
4.444439 |
| a (au) |
10.450297 |
| i (deg) |
4.567063 |
| Ω (om, deg) |
179.842795 |
| ω (w, deg) |
307.197933 |
| M (ma, deg) |
0.430116 |
等級
散乱 + 全体線形
$$
M_a = (5.108 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
5.108 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.507 |
| 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 |
| 2013-11-27 |
2014-10-24 |
+27.9138 |
-19.052 |
| 2015-01-17 |
2016-05-05 |
+3.0612 |
-2.167 |
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 |
19:03:14.70 |
-17:57:44.6 |
HIP 93644 |
17.65 |
| 2026-09-20 12:00 |
19:03:13.80 |
-17:57:56.4 |
HIP 93644 |
17.94 |
| 2026-09-21 00:00 |
19:03:12.97 |
-17:58:08.0 |
HIP 93644 |
18.22 |
| 2026-09-21 12:00 |
19:03:12.22 |
-17:58:19.6 |
HIP 93644 |
18.48 |
| 2026-09-22 00:00 |
19:03:11.53 |
-17:58:31.0 |
HIP 93644 |
18.73 |
| 2026-09-22 12:00 |
19:03:10.92 |
-17:58:42.4 |
HIP 93644 |
18.97 |
| 2026-09-23 00:00 |
19:03:10.38 |
-17:58:53.6 |
HIP 93644 |
19.19 |
| 2026-09-23 12:00 |
19:03:09.92 |
-17:59:04.8 |
HIP 93644 |
19.40 |
| 2026-09-24 00:00 |
19:03:09.52 |
-17:59:15.8 |
HIP 93644 |
19.59 |
| 2026-09-24 12:00 |
19:03:09.20 |
-17:59:26.7 |
HIP 93644 |
19.77 |
| 2026-09-25 00:00 |
19:03:08.96 |
-17:59:37.6 |
HIP 93644 |
19.94 |
| 2026-09-25 12:00 |
19:03:08.78 |
-17:59:48.3 |
HIP 93644 |
20.10 |
| 2026-09-26 00:00 |
19:03:08.68 |
-17:59:58.9 |
HIP 93644 |
20.24 |
| 2026-09-26 12:00 |
19:03:08.65 |
-18:00:09.4 |
HIP 93644 |
20.37 |
| 2026-09-27 00:00 |
19:03:08.69 |
-18:00:19.8 |
HIP 93644 |
20.49 |
| 2026-09-27 12:00 |
19:03:08.81 |
-18:00:30.1 |
HIP 93644 |
20.59 |
| 2026-09-28 00:00 |
19:03:09.00 |
-18:00:40.3 |
HIP 93644 |
20.68 |
| 2026-09-28 12:00 |
19:03:09.26 |
-18:00:50.3 |
HIP 93644 |
20.76 |
| 2026-09-29 00:00 |
19:03:09.59 |
-18:01:00.3 |
HIP 93644 |
20.83 |
| 2026-09-29 12:00 |
19:03:10.00 |
-18:01:10.1 |
HIP 93644 |
20.89 |
| 2026-09-30 00:00 |
19:03:10.48 |
-18:01:19.9 |
HIP 93644 |
20.93 |
| 2026-09-30 12:00 |
19:03:11.03 |
-18:01:29.5 |
HIP 93644 |
20.96 |
| 2026-10-01 00:00 |
19:03:11.66 |
-18:01:39.0 |
HIP 93644 |
20.99 |
| 2026-10-01 12:00 |
19:03:12.36 |
-18:01:48.4 |
HIP 93644 |
21.00 |
| 2026-10-02 00:00 |
19:03:13.13 |
-18:01:57.7 |
HIP 93644 |
21.01 |
| 2026-10-02 12:00 |
19:03:13.97 |
-18:02:06.9 |
HIP 93644 |
21.00 |
| 2026-10-03 00:00 |
19:03:14.88 |
-18:02:15.9 |
HIP 93644 |
20.98 |
| 2026-10-03 12:00 |
19:03:15.87 |
-18:02:24.8 |
HIP 93644 |
20.96 |
| 2026-10-04 00:00 |
19:03:16.93 |
-18:02:33.7 |
HIP 93644 |
20.93 |
| 2026-10-04 12:00 |
19:03:18.07 |
-18:02:42.4 |
HIP 93644 |
20.89 |
| 2026-10-05 00:00 |
19:03:19.28 |
-18:02:50.9 |
HIP 93644 |
20.84 |
| 2026-10-05 12:00 |
19:03:20.56 |
-18:02:59.4 |
HIP 93644 |
20.79 |
| 2026-10-06 00:00 |
19:03:21.91 |
-18:03:07.7 |
HIP 93644 |
20.73 |
| 2026-10-06 12:00 |
19:03:23.33 |
-18:03:15.9 |
HIP 93644 |
20.67 |
| 2026-10-07 00:00 |
19:03:24.83 |
-18:03:24.0 |
HIP 93644 |
20.60 |
| 2026-10-07 12:00 |
19:03:26.40 |
-18:03:32.0 |
HIP 93644 |
20.53 |
| 2026-10-08 00:00 |
19:03:28.04 |
-18:03:39.8 |
HIP 93644 |
20.45 |
| 2026-10-08 12:00 |
19:03:29.76 |
-18:03:47.5 |
HIP 93644 |
20.38 |
| 2026-10-09 00:00 |
19:03:31.55 |
-18:03:55.1 |
HIP 93644 |
20.30 |
| 2026-10-09 12:00 |
19:03:33.40 |
-18:04:02.6 |
HIP 93644 |
20.23 |
| 2026-10-10 00:00 |
19:03:35.34 |
-18:04:09.9 |
HIP 93644 |
20.15 |
| 2026-10-10 12:00 |
19:03:37.34 |
-18:04:17.1 |
HIP 93644 |
20.08 |
| 2026-10-11 00:00 |
19:03:39.41 |
-18:04:24.2 |
HIP 93644 |
20.01 |