C/2012 F3 (PANSTARRS)
| Parameter |
Value |
| Designation |
C/2012 F3 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2015-04-06T16:44:17.200320Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:06Z |
| Obs used |
1763 |
| NEO |
- |
| M1 |
8.100 |
| K1 |
7.500 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2014-11-27.0000000 |
| e |
1.00163676 |
| q (au) |
3.456939 |
| a (au) |
-2112.060187 |
| i (deg) |
11.354698 |
| Ω (om, deg) |
164.617309 |
| ω (w, deg) |
104.020514 |
| M (ma, deg) |
-0.001327 |
Magnitude
Scatter + Global Linear
$$
M_a = (11.830 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
11.830 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.609 |
| k |
0.800 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2012-01-19 |
2015-04-02 |
+2.7355 |
-2.126 |
| 2015-04-10 |
2016-06-05 |
-2.9643 |
+1.982 |
| 2016-06-05 |
2016-09-23 |
-1.7407 |
+1.316 |
| 2016-09-23 |
2017-10-17 |
+7.8916 |
-5.843 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-02-03 00:00 |
02:48:53.72 |
+06:00:12.1 |
HIP 13170 |
20.19 |
| 2026-02-03 12:00 |
02:48:54.18 |
+06:00:26.3 |
HIP 13170 |
20.37 |
| 2026-02-04 00:00 |
02:48:54.69 |
+06:00:40.8 |
HIP 13170 |
20.55 |
| 2026-02-04 12:00 |
02:48:55.23 |
+06:00:55.4 |
HIP 13170 |
20.74 |
| 2026-02-05 00:00 |
02:48:55.82 |
+06:01:10.2 |
HIP 13170 |
20.93 |
| 2026-02-05 12:00 |
02:48:56.44 |
+06:01:25.2 |
HIP 13170 |
21.12 |
| 2026-02-06 00:00 |
02:48:57.11 |
+06:01:40.3 |
HIP 13170 |
21.31 |
| 2026-02-06 12:00 |
02:48:57.82 |
+06:01:55.6 |
HIP 13170 |
21.50 |
| 2026-02-07 00:00 |
02:48:58.56 |
+06:02:11.1 |
HIP 13170 |
21.70 |
| 2026-02-07 12:00 |
02:48:59.35 |
+06:02:26.7 |
HIP 13170 |
21.90 |
| 2026-02-08 00:00 |
02:49:00.17 |
+06:02:42.5 |
HIP 13170 |
22.10 |
| 2026-02-08 12:00 |
02:49:01.03 |
+06:02:58.5 |
HIP 13170 |
22.31 |
| 2026-02-09 00:00 |
02:49:01.94 |
+06:03:14.6 |
HIP 13170 |
22.52 |
| 2026-02-09 12:00 |
02:49:02.88 |
+06:03:30.9 |
HIP 13170 |
22.73 |
| 2026-02-10 00:00 |
02:49:03.87 |
+06:03:47.3 |
HIP 13170 |
22.95 |
| 2026-02-10 12:00 |
02:49:04.89 |
+06:04:03.9 |
HIP 13170 |
23.18 |
| 2026-02-11 00:00 |
02:49:05.95 |
+06:04:20.6 |
HIP 13170 |
23.40 |
| 2026-02-11 12:00 |
02:49:07.05 |
+06:04:37.5 |
HIP 13170 |
23.64 |
| 2026-02-12 00:00 |
02:49:08.19 |
+06:04:54.6 |
HIP 13170 |
23.87 |
| 2026-02-12 12:00 |
02:49:09.37 |
+06:05:11.8 |
HIP 13170 |
24.12 |
| 2026-02-13 00:00 |
02:49:10.59 |
+06:05:29.1 |
HIP 13170 |
24.37 |
| 2026-02-13 12:00 |
02:49:11.85 |
+06:05:46.7 |
HIP 13198 |
24.38 |
| 2026-02-14 00:00 |
02:49:13.15 |
+06:06:04.3 |
HIP 13198 |
23.98 |
| 2026-02-14 12:00 |
02:49:14.48 |
+06:06:22.1 |
HIP 13198 |
23.58 |
| 2026-02-15 00:00 |
02:49:15.86 |
+06:06:40.0 |
HIP 13198 |
23.17 |
| 2026-02-15 12:00 |
02:49:17.27 |
+06:06:58.1 |
HIP 13198 |
22.76 |
| 2026-02-16 00:00 |
02:49:18.72 |
+06:07:16.3 |
HIP 13198 |
22.34 |
| 2026-02-16 12:00 |
02:49:20.21 |
+06:07:34.7 |
HIP 13198 |
21.92 |
| 2026-02-17 00:00 |
02:49:21.74 |
+06:07:53.2 |
HIP 13198 |
21.50 |
| 2026-02-17 12:00 |
02:49:23.30 |
+06:08:11.8 |
HIP 13198 |
21.07 |
| 2026-02-18 00:00 |
02:49:24.91 |
+06:08:30.6 |
HIP 13198 |
20.65 |
| 2026-02-18 12:00 |
02:49:26.55 |
+06:08:49.5 |
HIP 13198 |
20.22 |
| 2026-02-19 00:00 |
02:49:28.23 |
+06:09:08.6 |
HIP 13198 |
19.79 |
| 2026-02-19 12:00 |
02:49:29.94 |
+06:09:27.7 |
HIP 13198 |
19.36 |
| 2026-02-20 00:00 |
02:49:31.70 |
+06:09:47.0 |
HIP 13198 |
18.93 |
| 2026-02-20 12:00 |
02:49:33.49 |
+06:10:06.4 |
HIP 13198 |
18.51 |
| 2026-02-21 00:00 |
02:49:35.32 |
+06:10:26.0 |
HIP 13198 |
18.08 |
| 2026-02-21 12:00 |
02:49:37.18 |
+06:10:45.7 |
HIP 13198 |
17.66 |
| 2026-02-22 00:00 |
02:49:39.08 |
+06:11:05.5 |
HIP 13198 |
17.25 |
| 2026-02-22 12:00 |
02:49:41.02 |
+06:11:25.4 |
HIP 13198 |
16.84 |
| 2026-02-23 00:00 |
02:49:43.00 |
+06:11:45.4 |
HIP 13198 |
16.44 |
| 2026-02-23 12:00 |
02:49:45.01 |
+06:12:05.5 |
HIP 13198 |
16.04 |
| 2026-02-24 00:00 |
02:49:47.05 |
+06:12:25.8 |
HIP 13198 |
15.66 |