| Parameter |
Value |
| Designation |
C/1975 V2 (Bradfield) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1975-12-21T04:20:57.010560Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:24Z |
| Obs used |
81 |
| NEO |
- |
| M1 |
10.400 |
| K1 |
16.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1975-12-22.0000000 |
| e |
1.00001538 |
| q (au) |
0.218721 |
| a (au) |
-14217.185675 |
| i (deg) |
70.626160 |
| Ω (om, deg) |
271.312759 |
| ω (w, deg) |
358.089866 |
| M (ma, deg) |
0.000000 |
Magnitude
Scatter + Global Linear
$$
M_a = (9.332 + 3.967\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
9.332 |
| n |
3.967 |
| gf |
0.800 |
| gb |
-0.640 |
| k |
0.800 |
| 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) |
| 2026-03-26 00:00 |
05:49:46.11 |
+30:51:54.9 |
HIP 27582 |
15.10 |
| 2026-03-26 12:00 |
05:49:46.33 |
+30:51:51.7 |
HIP 27582 |
15.11 |
| 2026-03-27 00:00 |
05:49:46.56 |
+30:51:48.6 |
HIP 27582 |
15.12 |
| 2026-03-27 12:00 |
05:49:46.82 |
+30:51:45.4 |
HIP 27582 |
15.13 |
| 2026-03-28 00:00 |
05:49:47.08 |
+30:51:42.3 |
HIP 27582 |
15.14 |
| 2026-03-28 12:00 |
05:49:47.37 |
+30:51:39.1 |
HIP 27582 |
15.15 |
| 2026-03-29 00:00 |
05:49:47.66 |
+30:51:36.0 |
HIP 27582 |
15.15 |
| 2026-03-29 12:00 |
05:49:47.98 |
+30:51:32.9 |
HIP 27582 |
15.16 |
| 2026-03-30 00:00 |
05:49:48.31 |
+30:51:29.8 |
HIP 27582 |
15.16 |
| 2026-03-30 12:00 |
05:49:48.65 |
+30:51:26.7 |
HIP 27582 |
15.16 |
| 2026-03-31 00:00 |
05:49:49.01 |
+30:51:23.6 |
HIP 27582 |
15.16 |
| 2026-03-31 12:00 |
05:49:49.38 |
+30:51:20.5 |
HIP 27582 |
15.15 |
| 2026-04-01 00:00 |
05:49:49.77 |
+30:51:17.5 |
HIP 27582 |
15.15 |
| 2026-04-01 12:00 |
05:49:50.18 |
+30:51:14.4 |
HIP 27582 |
15.15 |
| 2026-04-02 00:00 |
05:49:50.59 |
+30:51:11.4 |
HIP 27582 |
15.14 |
| 2026-04-02 12:00 |
05:49:51.03 |
+30:51:08.3 |
HIP 27582 |
15.13 |
| 2026-04-03 00:00 |
05:49:51.48 |
+30:51:05.3 |
HIP 27582 |
15.12 |
| 2026-04-03 12:00 |
05:49:51.94 |
+30:51:02.3 |
HIP 27582 |
15.11 |
| 2026-04-04 00:00 |
05:49:52.42 |
+30:50:59.3 |
HIP 27582 |
15.10 |
| 2026-04-04 12:00 |
05:49:52.91 |
+30:50:56.3 |
HIP 27582 |
15.09 |
| 2026-04-05 00:00 |
05:49:53.42 |
+30:50:53.3 |
HIP 27582 |
15.08 |
| 2026-04-05 12:00 |
05:49:53.94 |
+30:50:50.4 |
HIP 27582 |
15.07 |
| 2026-04-06 00:00 |
05:49:54.48 |
+30:50:47.4 |
HIP 27582 |
15.05 |
| 2026-04-06 12:00 |
05:49:55.03 |
+30:50:44.5 |
HIP 27582 |
15.04 |
| 2026-04-07 00:00 |
05:49:55.60 |
+30:50:41.5 |
HIP 27582 |
15.02 |
| 2026-04-07 12:00 |
05:49:56.18 |
+30:50:38.6 |
HIP 27582 |
15.01 |
| 2026-04-08 00:00 |
05:49:56.78 |
+30:50:35.7 |
HIP 27582 |
14.99 |
| 2026-04-08 12:00 |
05:49:57.39 |
+30:50:32.8 |
HIP 27582 |
14.97 |
| 2026-04-09 00:00 |
05:49:58.01 |
+30:50:29.9 |
HIP 27582 |
14.96 |
| 2026-04-09 12:00 |
05:49:58.65 |
+30:50:27.1 |
HIP 27582 |
14.94 |
| 2026-04-10 00:00 |
05:49:59.30 |
+30:50:24.2 |
HIP 27582 |
14.92 |
| 2026-04-10 12:00 |
05:49:59.97 |
+30:50:21.4 |
HIP 27582 |
14.90 |
| 2026-04-11 00:00 |
05:50:00.65 |
+30:50:18.6 |
HIP 27582 |
14.89 |
| 2026-04-11 12:00 |
05:50:01.35 |
+30:50:15.7 |
HIP 27582 |
14.87 |
| 2026-04-12 00:00 |
05:50:02.06 |
+30:50:12.9 |
HIP 27582 |
14.85 |
| 2026-04-12 12:00 |
05:50:02.78 |
+30:50:10.1 |
HIP 27582 |
14.84 |
| 2026-04-13 00:00 |
05:50:03.52 |
+30:50:07.4 |
HIP 27582 |
14.82 |
| 2026-04-13 12:00 |
05:50:04.27 |
+30:50:04.6 |
HIP 27582 |
14.81 |
| 2026-04-14 00:00 |
05:50:05.03 |
+30:50:01.9 |
HIP 27582 |
14.79 |
| 2026-04-14 12:00 |
05:50:05.81 |
+30:49:59.1 |
HIP 27582 |
14.78 |
| 2026-04-15 00:00 |
05:50:06.61 |
+30:49:56.4 |
HIP 27582 |
14.76 |
| 2026-04-15 12:00 |
05:50:07.41 |
+30:49:53.7 |
HIP 27582 |
14.75 |
| 2026-04-16 00:00 |
05:50:08.23 |
+30:49:51.0 |
HIP 27582 |
14.74 |