メタデータ
| 項目 |
値 |
| Designation |
C/2014 C2 (STEREO) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2014-02-18T05:53:19.752000Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:48Z |
| Obs used |
297 |
| NEO |
- |
| M1 |
14.400 |
| K1 |
9.300 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2014-03-08.0000000 |
| e |
1.00000000 |
| q (au) |
0.512340 |
| a (au) |
- |
| i (deg) |
135.502163 |
| Ω (om, deg) |
283.347106 |
| ω (w, deg) |
56.075501 |
| M (ma, deg) |
- |
等級
散乱 + 全体線形
$$
M_a = (15.851 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
15.851 |
| n |
6.000 |
| gf |
0.800 |
| gb |
-1.000 |
| k |
0.800 |
| 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 |
| 2014-01-31 |
2014-02-16 |
-109.8474 |
-24.213 |
| 2014-02-19 |
2014-04-21 |
-4.4994 |
+2.124 |
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) |
| 2026-07-29 00:00 |
05:00:31.87 |
-04:13:09.5 |
HIP 23475 |
33.29 |
| 2026-07-29 12:00 |
05:00:34.22 |
-04:13:27.7 |
HIP 23475 |
32.71 |
| 2026-07-30 00:00 |
05:00:36.56 |
-04:13:46.1 |
HIP 23475 |
32.14 |
| 2026-07-30 12:00 |
05:00:38.86 |
-04:14:04.6 |
HIP 23475 |
31.58 |
| 2026-07-31 00:00 |
05:00:41.15 |
-04:14:23.4 |
HIP 23475 |
31.02 |
| 2026-07-31 12:00 |
05:00:43.41 |
-04:14:42.3 |
HIP 23475 |
30.48 |
| 2026-08-01 00:00 |
05:00:45.64 |
-04:15:01.4 |
HIP 23475 |
29.95 |
| 2026-08-01 12:00 |
05:00:47.85 |
-04:15:20.7 |
HIP 23475 |
29.43 |
| 2026-08-02 00:00 |
05:00:50.03 |
-04:15:40.1 |
HIP 23475 |
28.92 |
| 2026-08-02 12:00 |
05:00:52.19 |
-04:15:59.7 |
HIP 23475 |
28.42 |
| 2026-08-03 00:00 |
05:00:54.33 |
-04:16:19.5 |
HIP 23475 |
27.93 |
| 2026-08-03 12:00 |
05:00:56.43 |
-04:16:39.5 |
HIP 23475 |
27.46 |
| 2026-08-04 00:00 |
05:00:58.52 |
-04:16:59.7 |
HIP 23475 |
27.00 |
| 2026-08-04 12:00 |
05:01:00.57 |
-04:17:20.0 |
HIP 23475 |
26.55 |
| 2026-08-05 00:00 |
05:01:02.60 |
-04:17:40.5 |
HIP 23475 |
26.12 |
| 2026-08-05 12:00 |
05:01:04.60 |
-04:18:01.1 |
HIP 23475 |
25.70 |
| 2026-08-06 00:00 |
05:01:06.58 |
-04:18:21.9 |
HIP 23475 |
25.29 |
| 2026-08-06 12:00 |
05:01:08.53 |
-04:18:42.9 |
HIP 23475 |
24.90 |
| 2026-08-07 00:00 |
05:01:10.46 |
-04:19:04.1 |
HIP 23475 |
24.53 |
| 2026-08-07 12:00 |
05:01:12.35 |
-04:19:25.4 |
HIP 23475 |
24.17 |
| 2026-08-08 00:00 |
05:01:14.22 |
-04:19:46.9 |
HIP 23475 |
23.83 |
| 2026-08-08 12:00 |
05:01:16.07 |
-04:20:08.5 |
HIP 23475 |
23.50 |
| 2026-08-09 00:00 |
05:01:17.88 |
-04:20:30.3 |
HIP 23475 |
23.20 |
| 2026-08-09 12:00 |
05:01:19.67 |
-04:20:52.3 |
HIP 23475 |
22.91 |
| 2026-08-10 00:00 |
05:01:21.43 |
-04:21:14.4 |
HIP 23475 |
22.64 |
| 2026-08-10 12:00 |
05:01:23.16 |
-04:21:36.7 |
HIP 23475 |
22.39 |
| 2026-08-11 00:00 |
05:01:24.86 |
-04:21:59.1 |
HIP 23475 |
22.15 |
| 2026-08-11 12:00 |
05:01:26.53 |
-04:22:21.7 |
HIP 23475 |
21.94 |
| 2026-08-12 00:00 |
05:01:28.18 |
-04:22:44.4 |
HIP 23475 |
21.75 |
| 2026-08-12 12:00 |
05:01:29.80 |
-04:23:07.3 |
HIP 23475 |
21.58 |
| 2026-08-13 00:00 |
05:01:31.39 |
-04:23:30.4 |
HIP 23475 |
21.42 |
| 2026-08-13 12:00 |
05:01:32.95 |
-04:23:53.5 |
HIP 23475 |
21.29 |
| 2026-08-14 00:00 |
05:01:34.48 |
-04:24:16.9 |
HIP 23475 |
21.18 |
| 2026-08-14 12:00 |
05:01:35.98 |
-04:24:40.4 |
HIP 23475 |
21.09 |
| 2026-08-15 00:00 |
05:01:37.45 |
-04:25:04.0 |
HIP 23475 |
21.02 |
| 2026-08-15 12:00 |
05:01:38.89 |
-04:25:27.8 |
HIP 23475 |
20.97 |
| 2026-08-16 00:00 |
05:01:40.30 |
-04:25:51.7 |
HIP 23475 |
20.95 |
| 2026-08-16 12:00 |
05:01:41.68 |
-04:26:15.7 |
HIP 23475 |
20.94 |
| 2026-08-17 00:00 |
05:01:43.04 |
-04:26:39.9 |
HIP 23475 |
20.95 |
| 2026-08-17 12:00 |
05:01:44.36 |
-04:27:04.2 |
HIP 23475 |
20.99 |
| 2026-08-18 00:00 |
05:01:45.65 |
-04:27:28.7 |
HIP 23475 |
21.04 |
| 2026-08-18 12:00 |
05:01:46.91 |
-04:27:53.2 |
HIP 23475 |
21.11 |
| 2026-08-19 00:00 |
05:01:48.14 |
-04:28:18.0 |
HIP 23475 |
21.21 |