C/2012 S3 (PANSTARRS)
| 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) |
| 2026-02-03 00:00 |
08:33:19.81 |
-10:11:57.0 |
HIP 42013 |
13.77 |
| 2026-02-03 12:00 |
08:33:15.45 |
-10:11:33.3 |
HIP 42013 |
13.98 |
| 2026-02-04 00:00 |
08:33:11.09 |
-10:11:09.5 |
HIP 42013 |
14.29 |
| 2026-02-04 12:00 |
08:33:06.74 |
-10:10:45.3 |
HIP 42013 |
14.67 |
| 2026-02-05 00:00 |
08:33:02.40 |
-10:10:20.9 |
HIP 42013 |
15.12 |
| 2026-02-05 12:00 |
08:32:58.07 |
-10:09:56.3 |
HIP 42013 |
15.64 |
| 2026-02-06 00:00 |
08:32:53.75 |
-10:09:31.4 |
HIP 42013 |
16.22 |
| 2026-02-06 12:00 |
08:32:49.43 |
-10:09:06.3 |
HIP 42013 |
16.86 |
| 2026-02-07 00:00 |
08:32:45.12 |
-10:08:40.9 |
HIP 42013 |
17.54 |
| 2026-02-07 12:00 |
08:32:40.82 |
-10:08:15.3 |
HIP 42013 |
18.26 |
| 2026-02-08 00:00 |
08:32:36.53 |
-10:07:49.4 |
HIP 42013 |
19.02 |
| 2026-02-08 12:00 |
08:32:32.25 |
-10:07:23.3 |
HIP 42013 |
19.82 |
| 2026-02-09 00:00 |
08:32:27.98 |
-10:06:56.9 |
HIP 42013 |
20.64 |
| 2026-02-09 12:00 |
08:32:23.72 |
-10:06:30.3 |
HIP 42013 |
21.49 |
| 2026-02-10 00:00 |
08:32:19.47 |
-10:06:03.5 |
HIP 42013 |
22.36 |
| 2026-02-10 12:00 |
08:32:15.23 |
-10:05:36.4 |
HIP 42013 |
23.25 |
| 2026-02-11 00:00 |
08:32:11.00 |
-10:05:09.1 |
HIP 42013 |
24.16 |
| 2026-02-11 12:00 |
08:32:06.78 |
-10:04:41.6 |
HIP 41733 |
23.51 |
| 2026-02-12 00:00 |
08:32:02.57 |
-10:04:13.8 |
HIP 41733 |
22.68 |
| 2026-02-12 12:00 |
08:31:58.38 |
-10:03:45.8 |
HIP 41733 |
21.88 |
| 2026-02-13 00:00 |
08:31:54.20 |
-10:03:17.6 |
HIP 41733 |
21.11 |
| 2026-02-13 12:00 |
08:31:50.04 |
-10:02:49.1 |
HIP 41733 |
20.39 |
| 2026-02-14 00:00 |
08:31:45.88 |
-10:02:20.5 |
HIP 41733 |
19.70 |
| 2026-02-14 12:00 |
08:31:41.74 |
-10:01:51.6 |
HIP 41733 |
19.07 |
| 2026-02-15 00:00 |
08:31:37.62 |
-10:01:22.5 |
HIP 41733 |
18.48 |
| 2026-02-15 12:00 |
08:31:33.50 |
-10:00:53.2 |
HIP 41733 |
17.95 |
| 2026-02-16 00:00 |
08:31:29.41 |
-10:00:23.7 |
HIP 41733 |
17.48 |
| 2026-02-16 12:00 |
08:31:25.33 |
-09:59:53.9 |
HIP 41733 |
17.08 |
| 2026-02-17 00:00 |
08:31:21.26 |
-09:59:24.0 |
HIP 41733 |
16.75 |
| 2026-02-17 12:00 |
08:31:17.21 |
-09:58:53.9 |
HIP 41733 |
16.49 |
| 2026-02-18 00:00 |
08:31:13.18 |
-09:58:23.5 |
HIP 41733 |
16.31 |
| 2026-02-18 12:00 |
08:31:09.16 |
-09:57:53.0 |
HIP 41733 |
16.21 |
| 2026-02-19 00:00 |
08:31:05.16 |
-09:57:22.2 |
HIP 41733 |
16.19 |
| 2026-02-19 12:00 |
08:31:01.18 |
-09:56:51.3 |
HIP 41733 |
16.25 |
| 2026-02-20 00:00 |
08:30:57.21 |
-09:56:20.2 |
HIP 41733 |
16.39 |
| 2026-02-20 12:00 |
08:30:53.27 |
-09:55:48.8 |
HIP 41733 |
16.61 |
| 2026-02-21 00:00 |
08:30:49.34 |
-09:55:17.3 |
HIP 41733 |
16.90 |
| 2026-02-21 12:00 |
08:30:45.43 |
-09:54:45.6 |
HIP 41662 |
16.44 |
| 2026-02-22 00:00 |
08:30:41.53 |
-09:54:13.8 |
HIP 41662 |
15.65 |
| 2026-02-22 12:00 |
08:30:37.66 |
-09:53:41.7 |
HIP 41662 |
14.91 |
| 2026-02-23 00:00 |
08:30:33.81 |
-09:53:09.5 |
HIP 41662 |
14.21 |
| 2026-02-23 12:00 |
08:30:29.98 |
-09:52:37.1 |
HIP 41662 |
13.57 |
| 2026-02-24 00:00 |
08:30:26.16 |
-09:52:04.5 |
HIP 41662 |
13.00 |