| Parameter |
Value |
| Designation |
C/1966 P2 (Barbon) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1966-04-17T18:42:45.604800Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:17Z |
| Obs used |
90 |
| NEO |
- |
| M1 |
5.600 |
| K1 |
11.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1966-09-13.0000000 |
| e |
0.99811001 |
| q (au) |
2.018741 |
| a (au) |
1068.123028 |
| i (deg) |
28.707616 |
| Ω (om, deg) |
167.689319 |
| ω (w, deg) |
136.165961 |
| M (ma, deg) |
0.004185 |
Magnitude
Scatter + Global Linear
$$
M_a = (4.104 + 4.736\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
4.104 |
| n |
4.736 |
| gf |
1.000 |
| gb |
-1.000 |
| 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) |
| 2026-03-26 00:00 |
07:08:08.80 |
-02:38:46.8 |
HIP 34494 |
11.09 |
| 2026-03-26 12:00 |
07:08:08.56 |
-02:38:37.4 |
HIP 34494 |
11.19 |
| 2026-03-27 00:00 |
07:08:08.32 |
-02:38:27.9 |
HIP 34494 |
11.30 |
| 2026-03-27 12:00 |
07:08:08.10 |
-02:38:18.5 |
HIP 34494 |
11.40 |
| 2026-03-28 00:00 |
07:08:07.90 |
-02:38:09.1 |
HIP 34494 |
11.51 |
| 2026-03-28 12:00 |
07:08:07.70 |
-02:37:59.7 |
HIP 34494 |
11.61 |
| 2026-03-29 00:00 |
07:08:07.52 |
-02:37:50.3 |
HIP 34494 |
11.71 |
| 2026-03-29 12:00 |
07:08:07.35 |
-02:37:40.9 |
HIP 34494 |
11.81 |
| 2026-03-30 00:00 |
07:08:07.19 |
-02:37:31.5 |
HIP 34494 |
11.91 |
| 2026-03-30 12:00 |
07:08:07.04 |
-02:37:22.1 |
HIP 34494 |
12.00 |
| 2026-03-31 00:00 |
07:08:06.91 |
-02:37:12.8 |
HIP 34494 |
12.10 |
| 2026-03-31 12:00 |
07:08:06.79 |
-02:37:03.5 |
HIP 34494 |
12.19 |
| 2026-04-01 00:00 |
07:08:06.68 |
-02:36:54.1 |
HIP 34494 |
12.28 |
| 2026-04-01 12:00 |
07:08:06.58 |
-02:36:44.8 |
HIP 34494 |
12.37 |
| 2026-04-02 00:00 |
07:08:06.49 |
-02:36:35.5 |
HIP 34494 |
12.46 |
| 2026-04-02 12:00 |
07:08:06.42 |
-02:36:26.3 |
HIP 34494 |
12.55 |
| 2026-04-03 00:00 |
07:08:06.36 |
-02:36:17.0 |
HIP 34494 |
12.63 |
| 2026-04-03 12:00 |
07:08:06.31 |
-02:36:07.8 |
HIP 34494 |
12.72 |
| 2026-04-04 00:00 |
07:08:06.27 |
-02:35:58.5 |
HIP 34494 |
12.80 |
| 2026-04-04 12:00 |
07:08:06.24 |
-02:35:49.3 |
HIP 34494 |
12.88 |
| 2026-04-05 00:00 |
07:08:06.23 |
-02:35:40.2 |
HIP 34494 |
12.96 |
| 2026-04-05 12:00 |
07:08:06.23 |
-02:35:31.0 |
HIP 34494 |
13.04 |
| 2026-04-06 00:00 |
07:08:06.24 |
-02:35:21.8 |
HIP 34494 |
13.11 |
| 2026-04-06 12:00 |
07:08:06.26 |
-02:35:12.7 |
HIP 34494 |
13.19 |
| 2026-04-07 00:00 |
07:08:06.30 |
-02:35:03.6 |
HIP 34494 |
13.26 |
| 2026-04-07 12:00 |
07:08:06.35 |
-02:34:54.5 |
HIP 34494 |
13.33 |
| 2026-04-08 00:00 |
07:08:06.40 |
-02:34:45.5 |
HIP 34494 |
13.41 |
| 2026-04-08 12:00 |
07:08:06.48 |
-02:34:36.4 |
HIP 34494 |
13.47 |
| 2026-04-09 00:00 |
07:08:06.56 |
-02:34:27.4 |
HIP 34494 |
13.54 |
| 2026-04-09 12:00 |
07:08:06.65 |
-02:34:18.5 |
HIP 34494 |
13.61 |
| 2026-04-10 00:00 |
07:08:06.76 |
-02:34:09.5 |
HIP 34494 |
13.68 |
| 2026-04-10 12:00 |
07:08:06.88 |
-02:34:00.6 |
HIP 34494 |
13.74 |
| 2026-04-11 00:00 |
07:08:07.01 |
-02:33:51.7 |
HIP 34494 |
13.80 |
| 2026-04-11 12:00 |
07:08:07.16 |
-02:33:42.8 |
HIP 34494 |
13.86 |
| 2026-04-12 00:00 |
07:08:07.31 |
-02:33:33.9 |
HIP 34494 |
13.93 |
| 2026-04-12 12:00 |
07:08:07.48 |
-02:33:25.1 |
HIP 34494 |
13.98 |
| 2026-04-13 00:00 |
07:08:07.66 |
-02:33:16.3 |
HIP 34494 |
14.04 |
| 2026-04-13 12:00 |
07:08:07.85 |
-02:33:07.6 |
HIP 34494 |
14.10 |
| 2026-04-14 00:00 |
07:08:08.06 |
-02:32:58.8 |
HIP 34494 |
14.15 |
| 2026-04-14 12:00 |
07:08:08.27 |
-02:32:50.1 |
HIP 34494 |
14.21 |
| 2026-04-15 00:00 |
07:08:08.50 |
-02:32:41.5 |
HIP 34494 |
14.26 |
| 2026-04-15 12:00 |
07:08:08.74 |
-02:32:32.8 |
HIP 34494 |
14.31 |
| 2026-04-16 00:00 |
07:08:08.99 |
-02:32:24.2 |
HIP 34494 |
14.37 |