C/2012 K1 (PANSTARRS)
| Parameter |
Value |
| Designation |
C/2012 K1 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2014-08-27T15:50:55.363200Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:09Z |
| Obs used |
7829 |
| NEO |
- |
| M1 |
7.300 |
| K1 |
6.750 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2014-02-09.0000000 |
| e |
1.00015292 |
| q (au) |
1.054597 |
| a (au) |
-6896.600671 |
| i (deg) |
142.428258 |
| Ω (om, deg) |
317.737649 |
| ω (w, deg) |
203.106601 |
| M (ma, deg) |
-0.000344 |
Magnitude
Scatter + Global Linear
$$
M_a = (11.415 + 2.384\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
11.415 |
| n |
2.384 |
| gf |
1.000 |
| gb |
-0.794 |
| 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 |
| 2012-05-14 |
2014-07-17 |
+1.6930 |
-1.293 |
| 2014-08-31 |
2014-10-31 |
+17.6052 |
-4.110 |
| 2014-10-31 |
2016-08-07 |
+3.7216 |
-1.212 |
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 |
21:18:28.22 |
-15:22:32.3 |
HIP 105285 |
21.93 |
| 2026-02-03 12:00 |
21:18:32.16 |
-15:22:12.1 |
HIP 105285 |
21.02 |
| 2026-02-04 00:00 |
21:18:36.09 |
-15:21:51.9 |
HIP 105285 |
20.13 |
| 2026-02-04 12:00 |
21:18:40.03 |
-15:21:31.7 |
HIP 105285 |
19.24 |
| 2026-02-05 00:00 |
21:18:43.97 |
-15:21:11.5 |
HIP 105285 |
18.37 |
| 2026-02-05 12:00 |
21:18:47.91 |
-15:20:51.3 |
HIP 105285 |
17.51 |
| 2026-02-06 00:00 |
21:18:51.85 |
-15:20:31.0 |
HIP 105285 |
16.67 |
| 2026-02-06 12:00 |
21:18:55.79 |
-15:20:10.8 |
HIP 105285 |
15.85 |
| 2026-02-07 00:00 |
21:18:59.73 |
-15:19:50.5 |
HIP 105285 |
15.06 |
| 2026-02-07 12:00 |
21:19:03.66 |
-15:19:30.3 |
HIP 105285 |
14.29 |
| 2026-02-08 00:00 |
21:19:07.60 |
-15:19:10.0 |
HIP 105285 |
13.55 |
| 2026-02-08 12:00 |
21:19:11.53 |
-15:18:49.8 |
HIP 105285 |
12.84 |
| 2026-02-09 00:00 |
21:19:15.46 |
-15:18:29.5 |
HIP 105285 |
12.18 |
| 2026-02-09 12:00 |
21:19:19.39 |
-15:18:09.3 |
HIP 105285 |
11.57 |
| 2026-02-10 00:00 |
21:19:23.32 |
-15:17:49.0 |
HIP 105285 |
11.02 |
| 2026-02-10 12:00 |
21:19:27.25 |
-15:17:28.8 |
HIP 105285 |
10.54 |
| 2026-02-11 00:00 |
21:19:31.17 |
-15:17:08.6 |
HIP 105285 |
10.13 |
| 2026-02-11 12:00 |
21:19:35.09 |
-15:16:48.3 |
HIP 105285 |
9.81 |
| 2026-02-12 00:00 |
21:19:39.00 |
-15:16:28.1 |
HIP 105285 |
9.58 |
| 2026-02-12 12:00 |
21:19:42.91 |
-15:16:07.9 |
HIP 105285 |
9.46 |
| 2026-02-13 00:00 |
21:19:46.82 |
-15:15:47.7 |
HIP 105285 |
9.44 |
| 2026-02-13 12:00 |
21:19:50.72 |
-15:15:27.5 |
HIP 105285 |
9.53 |
| 2026-02-14 00:00 |
21:19:54.62 |
-15:15:07.4 |
HIP 105285 |
9.72 |
| 2026-02-14 12:00 |
21:19:58.51 |
-15:14:47.2 |
HIP 105285 |
10.00 |
| 2026-02-15 00:00 |
21:20:02.39 |
-15:14:27.1 |
HIP 105285 |
10.37 |
| 2026-02-15 12:00 |
21:20:06.28 |
-15:14:06.9 |
HIP 105285 |
10.82 |
| 2026-02-16 00:00 |
21:20:10.15 |
-15:13:46.8 |
HIP 105285 |
11.34 |
| 2026-02-16 12:00 |
21:20:14.02 |
-15:13:26.8 |
HIP 105285 |
11.92 |
| 2026-02-17 00:00 |
21:20:17.88 |
-15:13:06.7 |
HIP 105285 |
12.55 |
| 2026-02-17 12:00 |
21:20:21.74 |
-15:12:46.7 |
HIP 105285 |
13.22 |
| 2026-02-18 00:00 |
21:20:25.58 |
-15:12:26.7 |
HIP 105285 |
13.93 |
| 2026-02-18 12:00 |
21:20:29.43 |
-15:12:06.7 |
HIP 105285 |
14.67 |
| 2026-02-19 00:00 |
21:20:33.26 |
-15:11:46.7 |
HIP 105285 |
15.43 |
| 2026-02-19 12:00 |
21:20:37.08 |
-15:11:26.8 |
HIP 105285 |
16.22 |
| 2026-02-20 00:00 |
21:20:40.90 |
-15:11:06.9 |
HIP 105285 |
17.02 |
| 2026-02-20 12:00 |
21:20:44.71 |
-15:10:47.0 |
HIP 105285 |
17.85 |
| 2026-02-21 00:00 |
21:20:48.50 |
-15:10:27.2 |
HIP 105498 |
17.47 |
| 2026-02-21 12:00 |
21:20:52.29 |
-15:10:07.4 |
HIP 105498 |
16.55 |
| 2026-02-22 00:00 |
21:20:56.07 |
-15:09:47.7 |
HIP 105498 |
15.63 |
| 2026-02-22 12:00 |
21:20:59.84 |
-15:09:27.9 |
HIP 105498 |
14.71 |
| 2026-02-23 00:00 |
21:21:03.60 |
-15:09:08.3 |
HIP 105498 |
13.81 |
| 2026-02-23 12:00 |
21:21:07.35 |
-15:08:48.6 |
HIP 105498 |
12.92 |
| 2026-02-24 00:00 |
21:21:11.09 |
-15:08:29.0 |
HIP 105498 |
12.05 |