| Parameter |
Value |
| Designation |
C/2012 S3 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2013-08-31T03:14:37.167360Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:22Z |
| Obs used |
730 |
| NEO |
- |
| M1 |
13.700 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2013-05-22.0000000 |
| e |
1.00070829 |
| q (au) |
2.308066 |
| a (au) |
-3258.643490 |
| i (deg) |
112.930798 |
| Ω (om, deg) |
121.305818 |
| ω (w, deg) |
183.752733 |
| M (ma, deg) |
-0.000536 |
Magnitude
Scatter + Global Linear
$$
M_a = (12.451 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
12.451 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.996 |
| 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 |
08:27:23.56 |
-09:15:57.0 |
HIP 41433 |
10.05 |
| 2026-03-26 12:00 |
08:27:21.43 |
-09:15:19.0 |
HIP 41433 |
10.34 |
| 2026-03-27 00:00 |
08:27:19.32 |
-09:14:41.1 |
HIP 41433 |
10.68 |
| 2026-03-27 12:00 |
08:27:17.25 |
-09:14:03.1 |
HIP 41433 |
11.08 |
| 2026-03-28 00:00 |
08:27:15.22 |
-09:13:25.1 |
HIP 41433 |
11.53 |
| 2026-03-28 12:00 |
08:27:13.21 |
-09:12:47.1 |
HIP 41433 |
12.01 |
| 2026-03-29 00:00 |
08:27:11.24 |
-09:12:09.2 |
HIP 41433 |
12.53 |
| 2026-03-29 12:00 |
08:27:09.31 |
-09:11:31.2 |
HIP 41433 |
13.08 |
| 2026-03-30 00:00 |
08:27:07.41 |
-09:10:53.3 |
HIP 41433 |
13.65 |
| 2026-03-30 12:00 |
08:27:05.54 |
-09:10:15.4 |
HIP 41433 |
14.24 |
| 2026-03-31 00:00 |
08:27:03.70 |
-09:09:37.5 |
HIP 41433 |
14.85 |
| 2026-03-31 12:00 |
08:27:01.90 |
-09:08:59.6 |
HIP 41433 |
15.48 |
| 2026-04-01 00:00 |
08:27:00.13 |
-09:08:21.7 |
HIP 41433 |
16.12 |
| 2026-04-01 12:00 |
08:26:58.40 |
-09:07:43.9 |
HIP 41433 |
16.76 |
| 2026-04-02 00:00 |
08:26:56.70 |
-09:07:06.1 |
HIP 41433 |
17.42 |
| 2026-04-02 12:00 |
08:26:55.04 |
-09:06:28.3 |
HIP 41433 |
18.08 |
| 2026-04-03 00:00 |
08:26:53.41 |
-09:05:50.5 |
HIP 41433 |
18.75 |
| 2026-04-03 12:00 |
08:26:51.81 |
-09:05:12.8 |
HIP 41433 |
19.42 |
| 2026-04-04 00:00 |
08:26:50.25 |
-09:04:35.1 |
HIP 41303 |
19.38 |
| 2026-04-04 12:00 |
08:26:48.72 |
-09:03:57.5 |
HIP 41303 |
18.81 |
| 2026-04-05 00:00 |
08:26:47.23 |
-09:03:19.9 |
HIP 41303 |
18.25 |
| 2026-04-05 12:00 |
08:26:45.77 |
-09:02:42.4 |
HIP 41303 |
17.71 |
| 2026-04-06 00:00 |
08:26:44.35 |
-09:02:04.9 |
HIP 41303 |
17.19 |
| 2026-04-06 12:00 |
08:26:42.96 |
-09:01:27.4 |
HIP 41303 |
16.70 |
| 2026-04-07 00:00 |
08:26:41.61 |
-09:00:50.0 |
HIP 41303 |
16.23 |
| 2026-04-07 12:00 |
08:26:40.29 |
-09:00:12.7 |
HIP 41303 |
15.79 |
| 2026-04-08 00:00 |
08:26:39.01 |
-08:59:35.4 |
HIP 41303 |
15.38 |
| 2026-04-08 12:00 |
08:26:37.76 |
-08:58:58.1 |
HIP 41303 |
14.99 |
| 2026-04-09 00:00 |
08:26:36.55 |
-08:58:21.0 |
HIP 41303 |
14.64 |
| 2026-04-09 12:00 |
08:26:35.37 |
-08:57:43.8 |
HIP 41303 |
14.32 |
| 2026-04-10 00:00 |
08:26:34.23 |
-08:57:06.8 |
HIP 41303 |
14.04 |
| 2026-04-10 12:00 |
08:26:33.12 |
-08:56:29.8 |
HIP 41303 |
13.79 |
| 2026-04-11 00:00 |
08:26:32.05 |
-08:55:52.9 |
HIP 41303 |
13.58 |
| 2026-04-11 12:00 |
08:26:31.01 |
-08:55:16.1 |
HIP 41303 |
13.41 |
| 2026-04-12 00:00 |
08:26:30.01 |
-08:54:39.3 |
HIP 41303 |
13.27 |
| 2026-04-12 12:00 |
08:26:29.04 |
-08:54:02.7 |
HIP 41303 |
13.18 |
| 2026-04-13 00:00 |
08:26:28.11 |
-08:53:26.1 |
HIP 41303 |
13.13 |
| 2026-04-13 12:00 |
08:26:27.22 |
-08:52:49.6 |
HIP 41303 |
13.12 |
| 2026-04-14 00:00 |
08:26:26.36 |
-08:52:13.1 |
HIP 41303 |
13.14 |
| 2026-04-14 12:00 |
08:26:25.53 |
-08:51:36.8 |
HIP 41303 |
13.21 |
| 2026-04-15 00:00 |
08:26:24.75 |
-08:51:00.5 |
HIP 41303 |
13.31 |
| 2026-04-15 12:00 |
08:26:23.99 |
-08:50:24.4 |
HIP 41303 |
13.45 |
| 2026-04-16 00:00 |
08:26:23.28 |
-08:49:48.3 |
HIP 41303 |
13.62 |