C/1976 E1 (Bradfield)

Metadata

Parameter Value
Designation C/1976 E1 (Bradfield)
Type C
Perihelion (tp_cal, UTC) 1976-02-25T01:22:13.275840Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:29:24Z
Obs used 12
NEO -
M1 11.700
K1 10.000
PC -
Osculating Elements
Parameter Value
Epoch (epoch_cal, TDB) 1976-03-12.0000000
e 0.99987070
q (au) 0.678293
a (au) 5245.712828
i (deg) 147.778213
Ω (om, deg) 70.213442
ω (w, deg) 221.765775
M (ma, deg) 0.000041

Magnitude

C/1976 E1 (Bradfield) · Magnitude (Full range)

Scatter + Global Linear

$$ M_a = (14.087 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

Model Parameters

Parameter Value
H0 14.087
n 6.000
gf 1.000
gb -1.000
k 0.972
δ90 10.000
Parameter Symbol Range Description
Absolute magnitude at 1 AU from Sun and Earth H0 -5 to 20 Intrinsic brightness of the comet
Photometric slope parameter n 2 to 6 Rate of brightness change with heliocentric distance
Forward scattering asymmetry factor gf 0.8 to 1 Degree of forward scattering
Backward scattering asymmetry factor gb -1 to -0.5 Degree of backward scattering
Partitioning coefficient k 0.8 to 1 Ratio between forward/backward scattering contributions
Dust-to-gas brightness ratio δ90 1 to 10 Relative contribution of dust scattering to gas emission

Reference: EPSC-DPS2025-160

Ephemeris

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-06-01 00:00 02:18:32.39 +30:35:37.5 HIP 10884 31.40
2026-06-01 12:00 02:18:33.81 +30:35:47.5 HIP 10884 31.34
2026-06-02 00:00 02:18:35.22 +30:35:57.5 HIP 10884 31.28
2026-06-02 12:00 02:18:36.62 +30:36:07.5 HIP 10884 31.23
2026-06-03 00:00 02:18:38.02 +30:36:17.5 HIP 10884 31.18
2026-06-03 12:00 02:18:39.40 +30:36:27.5 HIP 10884 31.14
2026-06-04 00:00 02:18:40.78 +30:36:37.5 HIP 10884 31.10
2026-06-04 12:00 02:18:42.15 +30:36:47.5 HIP 10954 30.83
2026-06-05 00:00 02:18:43.51 +30:36:57.6 HIP 10954 30.52
2026-06-05 12:00 02:18:44.87 +30:37:07.6 HIP 10954 30.22
2026-06-06 00:00 02:18:46.21 +30:37:17.7 HIP 10954 29.91
2026-06-06 12:00 02:18:47.55 +30:37:27.7 HIP 10954 29.61
2026-06-07 00:00 02:18:48.87 +30:37:37.8 HIP 10954 29.30
2026-06-07 12:00 02:18:50.19 +30:37:47.9 HIP 10954 29.01
2026-06-08 00:00 02:18:51.50 +30:37:58.0 HIP 10954 28.71
2026-06-08 12:00 02:18:52.80 +30:38:08.1 HIP 10954 28.42
2026-06-09 00:00 02:18:54.09 +30:38:18.2 HIP 10954 28.13
2026-06-09 12:00 02:18:55.37 +30:38:28.3 HIP 10954 27.84
2026-06-10 00:00 02:18:56.64 +30:38:38.4 HIP 10954 27.55
2026-06-10 12:00 02:18:57.91 +30:38:48.5 HIP 10954 27.27
2026-06-11 00:00 02:18:59.16 +30:38:58.6 HIP 10954 26.99
2026-06-11 12:00 02:19:00.40 +30:39:08.7 HIP 10954 26.72
2026-06-12 00:00 02:19:01.63 +30:39:18.8 HIP 10954 26.44
2026-06-12 12:00 02:19:02.86 +30:39:28.9 HIP 10954 26.17
2026-06-13 00:00 02:19:04.07 +30:39:39.0 HIP 10954 25.91
2026-06-13 12:00 02:19:05.27 +30:39:49.1 HIP 10954 25.64
2026-06-14 00:00 02:19:06.47 +30:39:59.2 HIP 10954 25.38
2026-06-14 12:00 02:19:07.65 +30:40:09.3 HIP 10954 25.12
2026-06-15 00:00 02:19:08.82 +30:40:19.4 HIP 10954 24.87
2026-06-15 12:00 02:19:09.98 +30:40:29.4 HIP 10954 24.62
2026-06-16 00:00 02:19:11.13 +30:40:39.5 HIP 10954 24.37
2026-06-16 12:00 02:19:12.27 +30:40:49.6 HIP 10954 24.13
2026-06-17 00:00 02:19:13.40 +30:40:59.7 HIP 10954 23.89
2026-06-17 12:00 02:19:14.52 +30:41:09.7 HIP 10954 23.65
2026-06-18 00:00 02:19:15.63 +30:41:19.8 HIP 10954 23.42
2026-06-18 12:00 02:19:16.73 +30:41:29.8 HIP 10954 23.19
2026-06-19 00:00 02:19:17.81 +30:41:39.8 HIP 10954 22.96
2026-06-19 12:00 02:19:18.89 +30:41:49.8 HIP 10954 22.74
2026-06-20 00:00 02:19:19.95 +30:41:59.8 HIP 10954 22.52
2026-06-20 12:00 02:19:21.00 +30:42:09.8 HIP 10954 22.31
2026-06-21 00:00 02:19:22.05 +30:42:19.8 HIP 10954 22.10
2026-06-21 12:00 02:19:23.07 +30:42:29.8 HIP 10954 21.89
2026-06-22 00:00 02:19:24.09 +30:42:39.7 HIP 10954 21.69