| Parameter |
Value |
| Designation |
C/1984 A1 (Bradfield 1) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1983-12-27T19:07:03.864000Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:31Z |
| Obs used |
33 |
| NEO |
- |
| M1 |
- |
| K1 |
- |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1984-02-25.0000000 |
| e |
0.95231517 |
| q (au) |
1.357490 |
| a (au) |
28.467973 |
| i (deg) |
51.800566 |
| Ω (om, deg) |
356.858343 |
| ω (w, deg) |
219.164863 |
| M (ma, deg) |
0.384163 |
Magnitude
Scatter + Global Linear
$$
M_a = (7.897 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
7.897 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.500 |
| k |
1.000 |
| 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 |
00:29:07.25 |
+30:13:14.9 |
HIP 2326 |
8.25 |
| 2026-06-01 12:00 |
00:29:08.49 |
+30:13:36.7 |
HIP 2326 |
8.17 |
| 2026-06-02 00:00 |
00:29:09.71 |
+30:13:58.5 |
HIP 2326 |
8.11 |
| 2026-06-02 12:00 |
00:29:10.91 |
+30:14:20.2 |
HIP 2326 |
8.09 |
| 2026-06-03 00:00 |
00:29:12.09 |
+30:14:42.0 |
HIP 2326 |
8.09 |
| 2026-06-03 12:00 |
00:29:13.25 |
+30:15:03.6 |
HIP 2326 |
8.11 |
| 2026-06-04 00:00 |
00:29:14.39 |
+30:15:25.3 |
HIP 2326 |
8.17 |
| 2026-06-04 12:00 |
00:29:15.51 |
+30:15:46.9 |
HIP 2326 |
8.25 |
| 2026-06-05 00:00 |
00:29:16.61 |
+30:16:08.5 |
HIP 2326 |
8.35 |
| 2026-06-05 12:00 |
00:29:17.70 |
+30:16:30.0 |
HIP 2326 |
8.48 |
| 2026-06-06 00:00 |
00:29:18.76 |
+30:16:51.6 |
HIP 2326 |
8.63 |
| 2026-06-06 12:00 |
00:29:19.81 |
+30:17:13.0 |
HIP 2326 |
8.79 |
| 2026-06-07 00:00 |
00:29:20.83 |
+30:17:34.5 |
HIP 2326 |
8.98 |
| 2026-06-07 12:00 |
00:29:21.84 |
+30:17:55.8 |
HIP 2326 |
9.18 |
| 2026-06-08 00:00 |
00:29:22.82 |
+30:18:17.2 |
HIP 2326 |
9.40 |
| 2026-06-08 12:00 |
00:29:23.78 |
+30:18:38.5 |
HIP 2326 |
9.63 |
| 2026-06-09 00:00 |
00:29:24.73 |
+30:18:59.8 |
HIP 2326 |
9.88 |
| 2026-06-09 12:00 |
00:29:25.65 |
+30:19:21.0 |
HIP 2326 |
10.14 |
| 2026-06-10 00:00 |
00:29:26.56 |
+30:19:42.1 |
HIP 2326 |
10.40 |
| 2026-06-10 12:00 |
00:29:27.44 |
+30:20:03.2 |
HIP 2326 |
10.68 |
| 2026-06-11 00:00 |
00:29:28.31 |
+30:20:24.3 |
HIP 2326 |
10.96 |
| 2026-06-11 12:00 |
00:29:29.15 |
+30:20:45.3 |
HIP 2326 |
11.25 |
| 2026-06-12 00:00 |
00:29:29.97 |
+30:21:06.2 |
HIP 2326 |
11.55 |
| 2026-06-12 12:00 |
00:29:30.77 |
+30:21:27.1 |
HIP 2326 |
11.85 |
| 2026-06-13 00:00 |
00:29:31.55 |
+30:21:48.0 |
HIP 2326 |
12.16 |
| 2026-06-13 12:00 |
00:29:32.31 |
+30:22:08.8 |
HIP 2326 |
12.47 |
| 2026-06-14 00:00 |
00:29:33.05 |
+30:22:29.5 |
HIP 2326 |
12.79 |
| 2026-06-14 12:00 |
00:29:33.77 |
+30:22:50.1 |
HIP 2326 |
13.11 |
| 2026-06-15 00:00 |
00:29:34.47 |
+30:23:10.7 |
HIP 2326 |
13.43 |
| 2026-06-15 12:00 |
00:29:35.14 |
+30:23:31.2 |
HIP 2326 |
13.75 |
| 2026-06-16 00:00 |
00:29:35.80 |
+30:23:51.7 |
HIP 2326 |
14.07 |
| 2026-06-16 12:00 |
00:29:36.43 |
+30:24:12.1 |
HIP 2326 |
14.40 |
| 2026-06-17 00:00 |
00:29:37.05 |
+30:24:32.4 |
HIP 2326 |
14.73 |
| 2026-06-17 12:00 |
00:29:37.64 |
+30:24:52.7 |
HIP 2326 |
15.06 |
| 2026-06-18 00:00 |
00:29:38.21 |
+30:25:12.9 |
HIP 2326 |
15.38 |
| 2026-06-18 12:00 |
00:29:38.76 |
+30:25:33.0 |
HIP 2326 |
15.71 |
| 2026-06-19 00:00 |
00:29:39.28 |
+30:25:53.0 |
HIP 2326 |
16.04 |
| 2026-06-19 12:00 |
00:29:39.79 |
+30:26:13.0 |
HIP 2326 |
16.37 |
| 2026-06-20 00:00 |
00:29:40.27 |
+30:26:32.8 |
HIP 2326 |
16.70 |
| 2026-06-20 12:00 |
00:29:40.74 |
+30:26:52.6 |
HIP 2326 |
17.03 |
| 2026-06-21 00:00 |
00:29:41.18 |
+30:27:12.4 |
HIP 2326 |
17.35 |
| 2026-06-21 12:00 |
00:29:41.60 |
+30:27:32.0 |
HIP 2326 |
17.68 |
| 2026-06-22 00:00 |
00:29:42.00 |
+30:27:51.6 |
HIP 2326 |
18.01 |