メタデータ
| 項目 |
値 |
| Designation |
C/2005 S4 (McNaught) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2007-07-18T15:31:21.316800Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:53Z |
| Obs used |
580 |
| NEO |
- |
| M1 |
9.900 |
| K1 |
5.500 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2007-06-06.0000000 |
| e |
0.99897119 |
| q (au) |
5.850108 |
| a (au) |
5686.269098 |
| i (deg) |
107.958958 |
| Ω (om, deg) |
318.290291 |
| ω (w, deg) |
31.453945 |
| M (ma, deg) |
359.999902 |
等級
散乱 + 全体線形
$$
M_a = (6.966 + 3.745\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
6.966 |
| n |
3.745 |
| gf |
0.995 |
| gb |
-0.897 |
| k |
0.999 |
| 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 |
| 2005-07-27 |
2007-07-16 |
-1.0253 |
+0.679 |
| 2007-07-19 |
2008-10-06 |
+18.7523 |
-14.647 |
| 2008-10-06 |
2009-07-23 |
+4.6293 |
-3.301 |
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) |
| 2026-05-12 00:00 |
10:00:26.38 |
+29:12:12.2 |
HIP 49109 |
25.90 |
| 2026-05-12 12:00 |
10:00:25.69 |
+29:11:55.8 |
HIP 49109 |
26.21 |
| 2026-05-13 00:00 |
10:00:25.03 |
+29:11:39.1 |
HIP 49109 |
26.53 |
| 2026-05-13 12:00 |
10:00:24.40 |
+29:11:22.4 |
HIP 49109 |
26.84 |
| 2026-05-14 00:00 |
10:00:23.80 |
+29:11:05.5 |
HIP 49103 |
26.82 |
| 2026-05-14 12:00 |
10:00:23.23 |
+29:10:48.4 |
HIP 49103 |
26.63 |
| 2026-05-15 00:00 |
10:00:22.70 |
+29:10:31.3 |
HIP 49103 |
26.42 |
| 2026-05-15 12:00 |
10:00:22.19 |
+29:10:13.9 |
HIP 49103 |
26.22 |
| 2026-05-16 00:00 |
10:00:21.72 |
+29:09:56.5 |
HIP 49103 |
26.01 |
| 2026-05-16 12:00 |
10:00:21.27 |
+29:09:38.9 |
HIP 49103 |
25.80 |
| 2026-05-17 00:00 |
10:00:20.86 |
+29:09:21.1 |
HIP 49103 |
25.59 |
| 2026-05-17 12:00 |
10:00:20.48 |
+29:09:03.2 |
HIP 49103 |
25.37 |
| 2026-05-18 00:00 |
10:00:20.13 |
+29:08:45.2 |
HIP 49103 |
25.15 |
| 2026-05-18 12:00 |
10:00:19.81 |
+29:08:27.1 |
HIP 49103 |
24.92 |
| 2026-05-19 00:00 |
10:00:19.52 |
+29:08:08.8 |
HIP 49103 |
24.70 |
| 2026-05-19 12:00 |
10:00:19.27 |
+29:07:50.4 |
HIP 49103 |
24.47 |
| 2026-05-20 00:00 |
10:00:19.04 |
+29:07:31.8 |
HIP 49103 |
24.23 |
| 2026-05-20 12:00 |
10:00:18.85 |
+29:07:13.1 |
HIP 49103 |
23.99 |
| 2026-05-21 00:00 |
10:00:18.68 |
+29:06:54.3 |
HIP 49103 |
23.75 |
| 2026-05-21 12:00 |
10:00:18.55 |
+29:06:35.4 |
HIP 49103 |
23.50 |
| 2026-05-22 00:00 |
10:00:18.44 |
+29:06:16.4 |
HIP 49103 |
23.25 |
| 2026-05-22 12:00 |
10:00:18.37 |
+29:05:57.2 |
HIP 49103 |
23.00 |
| 2026-05-23 00:00 |
10:00:18.33 |
+29:05:37.9 |
HIP 49103 |
22.74 |
| 2026-05-23 12:00 |
10:00:18.32 |
+29:05:18.5 |
HIP 49103 |
22.48 |
| 2026-05-24 00:00 |
10:00:18.34 |
+29:04:58.9 |
HIP 49103 |
22.21 |
| 2026-05-24 12:00 |
10:00:18.39 |
+29:04:39.3 |
HIP 49103 |
21.94 |
| 2026-05-25 00:00 |
10:00:18.46 |
+29:04:19.5 |
HIP 49103 |
21.67 |
| 2026-05-25 12:00 |
10:00:18.57 |
+29:03:59.6 |
HIP 49103 |
21.39 |
| 2026-05-26 00:00 |
10:00:18.71 |
+29:03:39.6 |
HIP 49103 |
21.11 |
| 2026-05-26 12:00 |
10:00:18.88 |
+29:03:19.5 |
HIP 49103 |
20.82 |
| 2026-05-27 00:00 |
10:00:19.08 |
+29:02:59.3 |
HIP 49103 |
20.54 |
| 2026-05-27 12:00 |
10:00:19.31 |
+29:02:39.0 |
HIP 49103 |
20.24 |
| 2026-05-28 00:00 |
10:00:19.57 |
+29:02:18.5 |
HIP 49103 |
19.94 |
| 2026-05-28 12:00 |
10:00:19.86 |
+29:01:58.0 |
HIP 49103 |
19.64 |
| 2026-05-29 00:00 |
10:00:20.18 |
+29:01:37.3 |
HIP 49103 |
19.34 |
| 2026-05-29 12:00 |
10:00:20.52 |
+29:01:16.6 |
HIP 49103 |
19.03 |
| 2026-05-30 00:00 |
10:00:20.90 |
+29:00:55.7 |
HIP 49103 |
18.71 |
| 2026-05-30 12:00 |
10:00:21.31 |
+29:00:34.7 |
HIP 49103 |
18.40 |
| 2026-05-31 00:00 |
10:00:21.74 |
+29:00:13.6 |
HIP 49103 |
18.07 |
| 2026-05-31 12:00 |
10:00:22.21 |
+28:59:52.5 |
HIP 49103 |
17.75 |
| 2026-06-01 00:00 |
10:00:22.70 |
+28:59:31.2 |
HIP 49103 |
17.42 |
| 2026-06-01 12:00 |
10:00:23.22 |
+28:59:09.8 |
HIP 49103 |
17.09 |
| 2026-06-02 00:00 |
10:00:23.77 |
+28:58:48.4 |
HIP 49103 |
16.75 |