| Parameter |
Value |
| Designation |
P/2012 C3 (PANSTARRS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2011-10-05T09:58:58.944000Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:02Z |
| Obs used |
20 |
| NEO |
- |
| M1 |
13.500 |
| K1 |
10.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2012-02-17.0000000 |
| e |
0.62652717 |
| q (au) |
3.624891 |
| a (au) |
9.705904 |
| i (deg) |
9.189868 |
| Ω (om, deg) |
135.441268 |
| ω (w, deg) |
344.851612 |
| M (ma, deg) |
4.386758 |
Magnitude
Scatter + Global Linear
$$
M_a = (15.290 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
15.290 |
| n |
2.000 |
| gf |
0.997 |
| gb |
-0.823 |
| 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 |
20:12:20.71 |
-17:31:34.0 |
HIP 99468 |
23.43 |
| 2026-03-26 12:00 |
20:12:25.21 |
-17:31:18.3 |
HIP 99710 |
24.33 |
| 2026-03-27 00:00 |
20:12:29.65 |
-17:31:02.8 |
HIP 99710 |
23.46 |
| 2026-03-27 12:00 |
20:12:34.04 |
-17:30:47.3 |
HIP 99710 |
22.62 |
| 2026-03-28 00:00 |
20:12:38.37 |
-17:30:32.1 |
HIP 99710 |
21.81 |
| 2026-03-28 12:00 |
20:12:42.64 |
-17:30:17.0 |
HIP 99710 |
21.03 |
| 2026-03-29 00:00 |
20:12:46.87 |
-17:30:02.0 |
HIP 99710 |
20.29 |
| 2026-03-29 12:00 |
20:12:51.03 |
-17:29:47.2 |
HIP 99710 |
19.58 |
| 2026-03-30 00:00 |
20:12:55.14 |
-17:29:32.6 |
HIP 99710 |
18.91 |
| 2026-03-30 12:00 |
20:12:59.20 |
-17:29:18.1 |
HIP 99710 |
18.29 |
| 2026-03-31 00:00 |
20:13:03.20 |
-17:29:03.7 |
HIP 99710 |
17.70 |
| 2026-03-31 12:00 |
20:13:07.14 |
-17:28:49.6 |
HIP 99710 |
17.16 |
| 2026-04-01 00:00 |
20:13:11.02 |
-17:28:35.5 |
HIP 99710 |
16.66 |
| 2026-04-01 12:00 |
20:13:14.85 |
-17:28:21.7 |
HIP 99710 |
16.21 |
| 2026-04-02 00:00 |
20:13:18.63 |
-17:28:08.0 |
HIP 99710 |
15.82 |
| 2026-04-02 12:00 |
20:13:22.34 |
-17:27:54.4 |
HIP 99710 |
15.47 |
| 2026-04-03 00:00 |
20:13:26.00 |
-17:27:41.1 |
HIP 99710 |
15.17 |
| 2026-04-03 12:00 |
20:13:29.60 |
-17:27:27.9 |
HIP 99710 |
14.93 |
| 2026-04-04 00:00 |
20:13:33.15 |
-17:27:14.8 |
HIP 99710 |
14.74 |
| 2026-04-04 12:00 |
20:13:36.63 |
-17:27:02.0 |
HIP 99710 |
14.60 |
| 2026-04-05 00:00 |
20:13:40.06 |
-17:26:49.3 |
HIP 99710 |
14.52 |
| 2026-04-05 12:00 |
20:13:43.43 |
-17:26:36.7 |
HIP 99710 |
14.48 |
| 2026-04-06 00:00 |
20:13:46.74 |
-17:26:24.4 |
HIP 99710 |
14.49 |
| 2026-04-06 12:00 |
20:13:49.99 |
-17:26:12.2 |
HIP 99710 |
14.55 |
| 2026-04-07 00:00 |
20:13:53.19 |
-17:26:00.1 |
HIP 99710 |
14.65 |
| 2026-04-07 12:00 |
20:13:56.32 |
-17:25:48.3 |
HIP 99710 |
14.78 |
| 2026-04-08 00:00 |
20:13:59.39 |
-17:25:36.6 |
HIP 99710 |
14.96 |
| 2026-04-08 12:00 |
20:14:02.41 |
-17:25:25.1 |
HIP 99710 |
15.16 |
| 2026-04-09 00:00 |
20:14:05.36 |
-17:25:13.8 |
HIP 99710 |
15.40 |
| 2026-04-09 12:00 |
20:14:08.26 |
-17:25:02.7 |
HIP 99710 |
15.66 |
| 2026-04-10 00:00 |
20:14:11.09 |
-17:24:51.7 |
HIP 99710 |
15.94 |
| 2026-04-10 12:00 |
20:14:13.87 |
-17:24:41.0 |
HIP 99710 |
16.24 |
| 2026-04-11 00:00 |
20:14:16.58 |
-17:24:30.4 |
HIP 99710 |
16.56 |
| 2026-04-11 12:00 |
20:14:19.24 |
-17:24:20.0 |
HIP 99710 |
16.89 |
| 2026-04-12 00:00 |
20:14:21.83 |
-17:24:09.7 |
HIP 99710 |
17.24 |
| 2026-04-12 12:00 |
20:14:24.36 |
-17:23:59.7 |
HIP 99710 |
17.59 |
| 2026-04-13 00:00 |
20:14:26.83 |
-17:23:49.9 |
HIP 99710 |
17.95 |
| 2026-04-13 12:00 |
20:14:29.23 |
-17:23:40.2 |
HIP 99710 |
18.31 |
| 2026-04-14 00:00 |
20:14:31.58 |
-17:23:30.7 |
HIP 99710 |
18.68 |
| 2026-04-14 12:00 |
20:14:33.86 |
-17:23:21.4 |
HIP 99710 |
19.05 |
| 2026-04-15 00:00 |
20:14:36.09 |
-17:23:12.4 |
HIP 99710 |
19.42 |
| 2026-04-15 12:00 |
20:14:38.25 |
-17:23:03.5 |
HIP 99710 |
19.78 |
| 2026-04-16 00:00 |
20:14:40.34 |
-17:22:54.8 |
HIP 99710 |
20.15 |