C/1975 E1 (Bradfield)

メタデータ

項目
Designation C/1975 E1 (Bradfield)
Type C
Perihelion (tp_cal, UTC) 1975-04-04T13:55:24.000960Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:29:24Z
Obs used 52
NEO -
M1 -
K1 -
PC 0.030
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 1975-06-11.0000000
e 1.00140639
q (au) 1.216946
a (au) -865.298894
i (deg) 55.243879
Ω (om, deg) 157.908852
ω (w, deg) 264.130708
M (ma, deg) 0.002611

等級

C/1975 E1 (Bradfield) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (10.105 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 10.105
n 6.000
gf 1.000
gb -0.804
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

天体暦

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-07-29 00:00 15:18:39.92 +34:26:33.3 HIP 74914 23.52
2026-07-29 12:00 15:18:39.48 +34:26:16.9 HIP 74914 23.24
2026-07-30 00:00 15:18:39.05 +34:26:00.5 HIP 74914 22.96
2026-07-30 12:00 15:18:38.63 +34:25:44.0 HIP 74914 22.68
2026-07-31 00:00 15:18:38.23 +34:25:27.4 HIP 74914 22.40
2026-07-31 12:00 15:18:37.84 +34:25:10.7 HIP 74914 22.12
2026-08-01 00:00 15:18:37.47 +34:24:54.0 HIP 74914 21.84
2026-08-01 12:00 15:18:37.11 +34:24:37.3 HIP 74914 21.56
2026-08-02 00:00 15:18:36.77 +34:24:20.4 HIP 74914 21.28
2026-08-02 12:00 15:18:36.44 +34:24:03.5 HIP 74914 20.99
2026-08-03 00:00 15:18:36.13 +34:23:46.6 HIP 74914 20.71
2026-08-03 12:00 15:18:35.83 +34:23:29.6 HIP 74914 20.42
2026-08-04 00:00 15:18:35.55 +34:23:12.5 HIP 74914 20.14
2026-08-04 12:00 15:18:35.28 +34:22:55.4 HIP 74914 19.85
2026-08-05 00:00 15:18:35.02 +34:22:38.2 HIP 74914 19.56
2026-08-05 12:00 15:18:34.78 +34:22:21.0 HIP 74914 19.28
2026-08-06 00:00 15:18:34.56 +34:22:03.7 HIP 74914 18.99
2026-08-06 12:00 15:18:34.35 +34:21:46.3 HIP 74914 18.70
2026-08-07 00:00 15:18:34.15 +34:21:29.0 HIP 74914 18.41
2026-08-07 12:00 15:18:33.97 +34:21:11.5 HIP 74914 18.12
2026-08-08 00:00 15:18:33.81 +34:20:54.1 HIP 74914 17.83
2026-08-08 12:00 15:18:33.66 +34:20:36.5 HIP 74914 17.53
2026-08-09 00:00 15:18:33.52 +34:20:19.0 HIP 74914 17.24
2026-08-09 12:00 15:18:33.40 +34:20:01.3 HIP 74914 16.95
2026-08-10 00:00 15:18:33.30 +34:19:43.7 HIP 74914 16.65
2026-08-10 12:00 15:18:33.21 +34:19:26.0 HIP 74914 16.36
2026-08-11 00:00 15:18:33.13 +34:19:08.2 HIP 74914 16.06
2026-08-11 12:00 15:18:33.07 +34:18:50.5 HIP 74914 15.77
2026-08-12 00:00 15:18:33.03 +34:18:32.6 HIP 74914 15.47
2026-08-12 12:00 15:18:33.00 +34:18:14.8 HIP 74914 15.17
2026-08-13 00:00 15:18:32.98 +34:17:56.9 HIP 74914 14.87
2026-08-13 12:00 15:18:32.98 +34:17:39.0 HIP 74914 14.57
2026-08-14 00:00 15:18:33.00 +34:17:21.0 HIP 74914 14.28
2026-08-14 12:00 15:18:33.03 +34:17:03.1 HIP 74914 13.98
2026-08-15 00:00 15:18:33.08 +34:16:45.1 HIP 74914 13.68
2026-08-15 12:00 15:18:33.14 +34:16:27.0 HIP 74914 13.38
2026-08-16 00:00 15:18:33.21 +34:16:09.0 HIP 74914 13.07
2026-08-16 12:00 15:18:33.30 +34:15:50.9 HIP 74914 12.77
2026-08-17 00:00 15:18:33.41 +34:15:32.8 HIP 74914 12.47
2026-08-17 12:00 15:18:33.53 +34:15:14.6 HIP 74914 12.17
2026-08-18 00:00 15:18:33.67 +34:14:56.5 HIP 74914 11.87
2026-08-18 12:00 15:18:33.82 +34:14:38.3 HIP 74914 11.56
2026-08-19 00:00 15:18:33.99 +34:14:20.1 HIP 74914 11.26