| Parameter |
Value |
| Designation |
C/1979 M1 (Bradfield) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1979-07-23T06:18:13.374720Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:27Z |
| Obs used |
25 |
| NEO |
- |
| M1 |
14.600 |
| K1 |
35.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1979-08-03.0000000 |
| e |
1.00003214 |
| q (au) |
0.413217 |
| a (au) |
-12856.433853 |
| i (deg) |
136.228721 |
| Ω (om, deg) |
164.217096 |
| ω (w, deg) |
47.651179 |
| M (ma, deg) |
0.000007 |
Magnitude
Scatter + Global Linear
$$
M_a = (11.901 + 5.224\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
11.901 |
| n |
5.224 |
| gf |
0.800 |
| gb |
-0.500 |
| k |
1.000 |
| δ90 |
1.000 |
| 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) |
| 2026-05-12 00:00 |
21:48:05.91 |
-40:50:13.5 |
HIP 107565 |
13.58 |
| 2026-05-12 12:00 |
21:48:06.04 |
-40:50:24.5 |
HIP 107565 |
13.49 |
| 2026-05-13 00:00 |
21:48:06.16 |
-40:50:35.5 |
HIP 107565 |
13.39 |
| 2026-05-13 12:00 |
21:48:06.26 |
-40:50:46.6 |
HIP 107565 |
13.30 |
| 2026-05-14 00:00 |
21:48:06.34 |
-40:50:57.7 |
HIP 107565 |
13.20 |
| 2026-05-14 12:00 |
21:48:06.40 |
-40:51:08.9 |
HIP 107565 |
13.10 |
| 2026-05-15 00:00 |
21:48:06.45 |
-40:51:20.2 |
HIP 107565 |
13.00 |
| 2026-05-15 12:00 |
21:48:06.48 |
-40:51:31.5 |
HIP 107565 |
12.90 |
| 2026-05-16 00:00 |
21:48:06.49 |
-40:51:42.9 |
HIP 107565 |
12.80 |
| 2026-05-16 12:00 |
21:48:06.49 |
-40:51:54.4 |
HIP 107565 |
12.70 |
| 2026-05-17 00:00 |
21:48:06.47 |
-40:52:05.9 |
HIP 107565 |
12.60 |
| 2026-05-17 12:00 |
21:48:06.43 |
-40:52:17.5 |
HIP 107565 |
12.49 |
| 2026-05-18 00:00 |
21:48:06.37 |
-40:52:29.1 |
HIP 107565 |
12.38 |
| 2026-05-18 12:00 |
21:48:06.30 |
-40:52:40.9 |
HIP 107565 |
12.28 |
| 2026-05-19 00:00 |
21:48:06.21 |
-40:52:52.6 |
HIP 107565 |
12.17 |
| 2026-05-19 12:00 |
21:48:06.10 |
-40:53:04.4 |
HIP 107565 |
12.06 |
| 2026-05-20 00:00 |
21:48:05.97 |
-40:53:16.3 |
HIP 107565 |
11.95 |
| 2026-05-20 12:00 |
21:48:05.83 |
-40:53:28.3 |
HIP 107565 |
11.83 |
| 2026-05-21 00:00 |
21:48:05.67 |
-40:53:40.3 |
HIP 107565 |
11.72 |
| 2026-05-21 12:00 |
21:48:05.49 |
-40:53:52.3 |
HIP 107565 |
11.61 |
| 2026-05-22 00:00 |
21:48:05.30 |
-40:54:04.4 |
HIP 107565 |
11.49 |
| 2026-05-22 12:00 |
21:48:05.09 |
-40:54:16.6 |
HIP 107565 |
11.38 |
| 2026-05-23 00:00 |
21:48:04.86 |
-40:54:28.8 |
HIP 107565 |
11.26 |
| 2026-05-23 12:00 |
21:48:04.62 |
-40:54:41.0 |
HIP 107565 |
11.14 |
| 2026-05-24 00:00 |
21:48:04.35 |
-40:54:53.3 |
HIP 107565 |
11.03 |
| 2026-05-24 12:00 |
21:48:04.08 |
-40:55:05.7 |
HIP 107565 |
10.91 |
| 2026-05-25 00:00 |
21:48:03.78 |
-40:55:18.1 |
HIP 107565 |
10.79 |
| 2026-05-25 12:00 |
21:48:03.47 |
-40:55:30.5 |
HIP 107565 |
10.67 |
| 2026-05-26 00:00 |
21:48:03.14 |
-40:55:43.0 |
HIP 107565 |
10.55 |
| 2026-05-26 12:00 |
21:48:02.79 |
-40:55:55.6 |
HIP 107565 |
10.43 |
| 2026-05-27 00:00 |
21:48:02.43 |
-40:56:08.2 |
HIP 107565 |
10.32 |
| 2026-05-27 12:00 |
21:48:02.04 |
-40:56:20.8 |
HIP 107565 |
10.20 |
| 2026-05-28 00:00 |
21:48:01.65 |
-40:56:33.5 |
HIP 107565 |
10.08 |
| 2026-05-28 12:00 |
21:48:01.23 |
-40:56:46.2 |
HIP 107565 |
9.96 |
| 2026-05-29 00:00 |
21:48:00.80 |
-40:56:58.9 |
HIP 107565 |
9.84 |
| 2026-05-29 12:00 |
21:48:00.35 |
-40:57:11.7 |
HIP 107565 |
9.73 |
| 2026-05-30 00:00 |
21:47:59.89 |
-40:57:24.6 |
HIP 107565 |
9.61 |
| 2026-05-30 12:00 |
21:47:59.41 |
-40:57:37.4 |
HIP 107565 |
9.49 |
| 2026-05-31 00:00 |
21:47:58.91 |
-40:57:50.3 |
HIP 107565 |
9.38 |
| 2026-05-31 12:00 |
21:47:58.40 |
-40:58:03.3 |
HIP 107565 |
9.27 |
| 2026-06-01 00:00 |
21:47:57.86 |
-40:58:16.3 |
HIP 107565 |
9.16 |
| 2026-06-01 12:00 |
21:47:57.32 |
-40:58:29.3 |
HIP 107565 |
9.05 |
| 2026-06-02 00:00 |
21:47:56.75 |
-40:58:42.3 |
HIP 107565 |
8.94 |