| Parameter |
Value |
| Designation |
C/2012 E3 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2011-05-12T22:05:22.326720Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:05Z |
| Obs used |
74 |
| NEO |
- |
| M1 |
9.900 |
| K1 |
10.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2012-03-29.0000000 |
| e |
0.98271491 |
| q (au) |
3.827319 |
| a (au) |
221.423057 |
| i (deg) |
105.658608 |
| Ω (om, deg) |
5.530998 |
| ω (w, deg) |
103.515422 |
| M (ma, deg) |
0.096047 |
Magnitude
Scatter + Global Linear
$$
M_a = (11.441 + 2.856\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
11.441 |
| n |
2.856 |
| gf |
0.800 |
| gb |
-0.500 |
| k |
0.976 |
| 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) |
| 2026-09-20 00:00 |
08:53:40.00 |
-44:30:30.0 |
HIP 43643 |
10.98 |
| 2026-09-20 12:00 |
08:53:43.02 |
-44:31:14.0 |
HIP 43643 |
11.84 |
| 2026-09-21 00:00 |
08:53:46.02 |
-44:31:58.2 |
HIP 43643 |
12.71 |
| 2026-09-21 12:00 |
08:53:48.99 |
-44:32:42.7 |
HIP 43643 |
13.59 |
| 2026-09-22 00:00 |
08:53:51.92 |
-44:33:27.4 |
HIP 43643 |
14.47 |
| 2026-09-22 12:00 |
08:53:54.83 |
-44:34:12.4 |
HIP 43643 |
15.36 |
| 2026-09-23 00:00 |
08:53:57.70 |
-44:34:57.6 |
HIP 43643 |
16.25 |
| 2026-09-23 12:00 |
08:54:00.54 |
-44:35:43.0 |
HIP 43643 |
17.15 |
| 2026-09-24 00:00 |
08:54:03.35 |
-44:36:28.6 |
HIP 43643 |
18.05 |
| 2026-09-24 12:00 |
08:54:06.13 |
-44:37:14.5 |
HIP 43643 |
18.95 |
| 2026-09-25 00:00 |
08:54:08.88 |
-44:38:00.6 |
HIP 43643 |
19.85 |
| 2026-09-25 12:00 |
08:54:11.59 |
-44:38:46.9 |
HIP 43643 |
20.75 |
| 2026-09-26 00:00 |
08:54:14.27 |
-44:39:33.4 |
HIP 43643 |
21.66 |
| 2026-09-26 12:00 |
08:54:16.92 |
-44:40:20.1 |
HIP 43643 |
22.56 |
| 2026-09-27 00:00 |
08:54:19.54 |
-44:41:07.1 |
HIP 43643 |
23.47 |
| 2026-09-27 12:00 |
08:54:22.12 |
-44:41:54.2 |
HIP 43807 |
22.95 |
| 2026-09-28 00:00 |
08:54:24.66 |
-44:42:41.6 |
HIP 43807 |
22.04 |
| 2026-09-28 12:00 |
08:54:27.18 |
-44:43:29.2 |
HIP 43807 |
21.13 |
| 2026-09-29 00:00 |
08:54:29.66 |
-44:44:16.9 |
HIP 43807 |
20.22 |
| 2026-09-29 12:00 |
08:54:32.10 |
-44:45:04.9 |
HIP 43807 |
19.31 |
| 2026-09-30 00:00 |
08:54:34.51 |
-44:45:53.0 |
HIP 43807 |
18.41 |
| 2026-09-30 12:00 |
08:54:36.89 |
-44:46:41.4 |
HIP 43807 |
17.50 |
| 2026-10-01 00:00 |
08:54:39.23 |
-44:47:29.9 |
HIP 43807 |
16.59 |
| 2026-10-01 12:00 |
08:54:41.54 |
-44:48:18.7 |
HIP 43807 |
15.68 |
| 2026-10-02 00:00 |
08:54:43.81 |
-44:49:07.6 |
HIP 43807 |
14.77 |
| 2026-10-02 12:00 |
08:54:46.04 |
-44:49:56.7 |
HIP 43807 |
13.86 |
| 2026-10-03 00:00 |
08:54:48.24 |
-44:50:45.9 |
HIP 43807 |
12.95 |
| 2026-10-03 12:00 |
08:54:50.41 |
-44:51:35.4 |
HIP 43807 |
12.04 |
| 2026-10-04 00:00 |
08:54:52.53 |
-44:52:25.0 |
HIP 43807 |
11.13 |
| 2026-10-04 12:00 |
08:54:54.62 |
-44:53:14.8 |
HIP 43807 |
10.23 |
| 2026-10-05 00:00 |
08:54:56.67 |
-44:54:04.7 |
HIP 43807 |
9.32 |
| 2026-10-05 12:00 |
08:54:58.69 |
-44:54:54.9 |
HIP 43807 |
8.41 |
| 2026-10-06 00:00 |
08:55:00.67 |
-44:55:45.1 |
HIP 43807 |
7.50 |
| 2026-10-06 12:00 |
08:55:02.61 |
-44:56:35.6 |
HIP 43807 |
6.60 |
| 2026-10-07 00:00 |
08:55:04.51 |
-44:57:26.2 |
HIP 43807 |
5.69 |
| 2026-10-07 12:00 |
08:55:06.37 |
-44:58:16.9 |
HIP 43807 |
4.79 |
| 2026-10-08 00:00 |
08:55:08.20 |
-44:59:07.8 |
HIP 43807 |
3.89 |
| 2026-10-08 12:00 |
08:55:09.99 |
-44:59:58.8 |
HIP 43807 |
3.00 |
| 2026-10-09 00:00 |
08:55:11.73 |
-45:00:50.0 |
HIP 43807 |
2.13 |
| 2026-10-09 12:00 |
08:55:13.44 |
-45:01:41.3 |
HIP 43807 |
1.30 |
| 2026-10-10 00:00 |
08:55:15.11 |
-45:02:32.7 |
HIP 43807 |
0.73 |
| 2026-10-10 12:00 |
08:55:16.74 |
-45:03:24.3 |
HIP 43807 |
1.00 |
| 2026-10-11 00:00 |
08:55:18.33 |
-45:04:16.0 |
HIP 43807 |
1.77 |