| Parameter |
Value |
| Designation |
C/2012 K6 (McNaught) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2013-05-21T11:03:28.212480Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:10Z |
| Obs used |
1091 |
| NEO |
- |
| M1 |
8.900 |
| K1 |
7.750 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2013-12-31.0000000 |
| e |
0.99919878 |
| q (au) |
3.353032 |
| a (au) |
4184.883889 |
| i (deg) |
135.215103 |
| Ω (om, deg) |
206.898541 |
| ω (w, deg) |
338.826785 |
| M (ma, deg) |
0.000814 |
Magnitude
Scatter + Global Linear
$$
M_a = (8.021 + 3.183\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
8.021 |
| n |
3.183 |
| gf |
0.997 |
| gb |
-1.000 |
| k |
1.000 |
| δ90 |
9.993 |
| 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 |
| 2012-04-20 |
2013-05-20 |
+12.1573 |
-6.871 |
| 2013-06-02 |
2014-01-30 |
-1.7355 |
+0.738 |
| 2014-01-30 |
2015-04-09 |
-2.5207 |
+1.571 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-06-01 00:00 |
04:49:35.68 |
+59:42:25.3 |
HIP 22434 |
8.47 |
| 2026-06-01 12:00 |
04:49:42.99 |
+59:42:25.7 |
HIP 22434 |
8.45 |
| 2026-06-02 00:00 |
04:49:50.30 |
+59:42:26.5 |
HIP 22434 |
8.54 |
| 2026-06-02 12:00 |
04:49:57.62 |
+59:42:27.5 |
HIP 22434 |
8.73 |
| 2026-06-03 00:00 |
04:50:04.93 |
+59:42:28.8 |
HIP 22434 |
9.01 |
| 2026-06-03 12:00 |
04:50:12.25 |
+59:42:30.4 |
HIP 22434 |
9.39 |
| 2026-06-04 00:00 |
04:50:19.57 |
+59:42:32.2 |
HIP 22434 |
9.84 |
| 2026-06-04 12:00 |
04:50:26.88 |
+59:42:34.4 |
HIP 22434 |
10.35 |
| 2026-06-05 00:00 |
04:50:34.20 |
+59:42:36.8 |
HIP 22434 |
10.93 |
| 2026-06-05 12:00 |
04:50:41.52 |
+59:42:39.5 |
HIP 22434 |
11.55 |
| 2026-06-06 00:00 |
04:50:48.83 |
+59:42:42.5 |
HIP 22434 |
12.22 |
| 2026-06-06 12:00 |
04:50:56.15 |
+59:42:45.8 |
HIP 22434 |
12.92 |
| 2026-06-07 00:00 |
04:51:03.46 |
+59:42:49.4 |
HIP 22434 |
13.65 |
| 2026-06-07 12:00 |
04:51:10.76 |
+59:42:53.3 |
HIP 22434 |
14.40 |
| 2026-06-08 00:00 |
04:51:18.07 |
+59:42:57.4 |
HIP 22434 |
15.18 |
| 2026-06-08 12:00 |
04:51:25.37 |
+59:43:01.8 |
HIP 22434 |
15.97 |
| 2026-06-09 00:00 |
04:51:32.67 |
+59:43:06.5 |
HIP 22434 |
16.78 |
| 2026-06-09 12:00 |
04:51:39.96 |
+59:43:11.5 |
HIP 22434 |
17.61 |
| 2026-06-10 00:00 |
04:51:47.25 |
+59:43:16.7 |
HIP 22434 |
18.44 |
| 2026-06-10 12:00 |
04:51:54.53 |
+59:43:22.3 |
HIP 22434 |
19.29 |
| 2026-06-11 00:00 |
04:52:01.81 |
+59:43:28.1 |
HIP 22434 |
20.14 |
| 2026-06-11 12:00 |
04:52:09.08 |
+59:43:34.2 |
HIP 22434 |
21.00 |
| 2026-06-12 00:00 |
04:52:16.34 |
+59:43:40.5 |
HIP 22434 |
21.87 |
| 2026-06-12 12:00 |
04:52:23.60 |
+59:43:47.2 |
HIP 22434 |
22.74 |
| 2026-06-13 00:00 |
04:52:30.85 |
+59:43:54.1 |
HIP 22434 |
23.62 |
| 2026-06-13 12:00 |
04:52:38.09 |
+59:44:01.3 |
HIP 22434 |
24.50 |
| 2026-06-14 00:00 |
04:52:45.32 |
+59:44:08.8 |
HIP 22434 |
25.38 |
| 2026-06-14 12:00 |
04:52:52.54 |
+59:44:16.6 |
HIP 22434 |
26.27 |
| 2026-06-15 00:00 |
04:52:59.75 |
+59:44:24.6 |
HIP 22434 |
27.16 |
| 2026-06-15 12:00 |
04:53:06.96 |
+59:44:32.9 |
HIP 22434 |
28.06 |
| 2026-06-16 00:00 |
04:53:14.15 |
+59:44:41.5 |
HIP 22434 |
28.95 |
| 2026-06-16 12:00 |
04:53:21.33 |
+59:44:50.3 |
HIP 22434 |
29.85 |
| 2026-06-17 00:00 |
04:53:28.49 |
+59:44:59.4 |
HIP 22434 |
30.75 |
| 2026-06-17 12:00 |
04:53:35.65 |
+59:45:08.8 |
HIP 22434 |
31.64 |
| 2026-06-18 00:00 |
04:53:42.79 |
+59:45:18.5 |
HIP 22434 |
32.54 |
| 2026-06-18 12:00 |
04:53:49.92 |
+59:45:28.4 |
HIP 22434 |
33.44 |
| 2026-06-19 00:00 |
04:53:57.03 |
+59:45:38.6 |
HIP 22434 |
34.35 |
| 2026-06-19 12:00 |
04:54:04.13 |
+59:45:49.0 |
HIP 22434 |
35.25 |
| 2026-06-20 00:00 |
04:54:11.22 |
+59:45:59.8 |
HIP 22434 |
36.15 |
| 2026-06-20 12:00 |
04:54:18.29 |
+59:46:10.8 |
HIP 22434 |
37.05 |
| 2026-06-21 00:00 |
04:54:25.34 |
+59:46:22.0 |
HIP 22434 |
37.95 |
| 2026-06-21 12:00 |
04:54:32.38 |
+59:46:33.5 |
HIP 22434 |
38.85 |
| 2026-06-22 00:00 |
04:54:39.40 |
+59:46:45.3 |
HIP 22434 |
39.75 |