| Parameter |
Value |
| Designation |
C/2011 Q2 (McNaught) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2012-01-19T18:55:25.829760Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:55Z |
| Obs used |
106 |
| NEO |
- |
| M1 |
4.700 |
| K1 |
23.250 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2011-09-16.0000000 |
| e |
1.00007496 |
| q (au) |
1.349561 |
| a (au) |
-18003.301883 |
| i (deg) |
36.866576 |
| Ω (om, deg) |
287.369526 |
| ω (w, deg) |
34.628570 |
| M (ma, deg) |
-0.000051 |
Magnitude
Scatter + Global Linear
$$
M_a = (10.734 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
10.734 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.500 |
| 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) |
| 2026-06-01 00:00 |
07:42:05.09 |
+14:38:44.9 |
HIP 37521 |
26.24 |
| 2026-06-01 12:00 |
07:42:07.87 |
+14:38:40.5 |
HIP 37521 |
26.19 |
| 2026-06-02 00:00 |
07:42:10.68 |
+14:38:36.0 |
HIP 37521 |
26.15 |
| 2026-06-02 12:00 |
07:42:13.51 |
+14:38:31.5 |
HIP 37521 |
26.13 |
| 2026-06-03 00:00 |
07:42:16.36 |
+14:38:26.8 |
HIP 37521 |
26.13 |
| 2026-06-03 12:00 |
07:42:19.23 |
+14:38:22.0 |
HIP 37521 |
26.14 |
| 2026-06-04 00:00 |
07:42:22.11 |
+14:38:17.2 |
HIP 37521 |
26.18 |
| 2026-06-04 12:00 |
07:42:25.02 |
+14:38:12.2 |
HIP 37521 |
26.23 |
| 2026-06-05 00:00 |
07:42:27.94 |
+14:38:07.2 |
HIP 37521 |
26.30 |
| 2026-06-05 12:00 |
07:42:30.88 |
+14:38:02.1 |
HIP 37521 |
26.39 |
| 2026-06-06 00:00 |
07:42:33.84 |
+14:37:56.9 |
HIP 37585 |
26.46 |
| 2026-06-06 12:00 |
07:42:36.82 |
+14:37:51.6 |
HIP 37585 |
26.47 |
| 2026-06-07 00:00 |
07:42:39.82 |
+14:37:46.2 |
HIP 37585 |
26.51 |
| 2026-06-07 12:00 |
07:42:42.83 |
+14:37:40.7 |
HIP 37585 |
26.57 |
| 2026-06-08 00:00 |
07:42:45.86 |
+14:37:35.1 |
HIP 37585 |
26.65 |
| 2026-06-08 12:00 |
07:42:48.91 |
+14:37:29.4 |
HIP 37585 |
26.76 |
| 2026-06-09 00:00 |
07:42:51.97 |
+14:37:23.7 |
HIP 37585 |
26.88 |
| 2026-06-09 12:00 |
07:42:55.05 |
+14:37:17.9 |
HIP 37585 |
27.03 |
| 2026-06-10 00:00 |
07:42:58.15 |
+14:37:11.9 |
HIP 37585 |
27.20 |
| 2026-06-10 12:00 |
07:43:01.27 |
+14:37:05.9 |
HIP 37585 |
27.39 |
| 2026-06-11 00:00 |
07:43:04.40 |
+14:36:59.8 |
HIP 37585 |
27.60 |
| 2026-06-11 12:00 |
07:43:07.54 |
+14:36:53.6 |
HIP 37585 |
27.83 |
| 2026-06-12 00:00 |
07:43:10.71 |
+14:36:47.3 |
HIP 37585 |
28.09 |
| 2026-06-12 12:00 |
07:43:13.89 |
+14:36:41.0 |
HIP 37585 |
28.36 |
| 2026-06-13 00:00 |
07:43:17.08 |
+14:36:34.5 |
HIP 37585 |
28.66 |
| 2026-06-13 12:00 |
07:43:20.29 |
+14:36:28.0 |
HIP 37708 |
28.68 |
| 2026-06-14 00:00 |
07:43:23.51 |
+14:36:21.3 |
HIP 37708 |
28.26 |
| 2026-06-14 12:00 |
07:43:26.75 |
+14:36:14.6 |
HIP 37708 |
27.86 |
| 2026-06-15 00:00 |
07:43:30.01 |
+14:36:07.8 |
HIP 37708 |
27.47 |
| 2026-06-15 12:00 |
07:43:33.27 |
+14:36:00.9 |
HIP 37836 |
26.92 |
| 2026-06-16 00:00 |
07:43:36.56 |
+14:35:54.0 |
HIP 37836 |
26.13 |
| 2026-06-16 12:00 |
07:43:39.85 |
+14:35:46.9 |
HIP 37836 |
25.33 |
| 2026-06-17 00:00 |
07:43:43.16 |
+14:35:39.7 |
HIP 37836 |
24.53 |
| 2026-06-17 12:00 |
07:43:46.48 |
+14:35:32.5 |
HIP 37836 |
23.73 |
| 2026-06-18 00:00 |
07:43:49.82 |
+14:35:25.2 |
HIP 37836 |
22.93 |
| 2026-06-18 12:00 |
07:43:53.17 |
+14:35:17.8 |
HIP 37836 |
22.12 |
| 2026-06-19 00:00 |
07:43:56.53 |
+14:35:10.3 |
HIP 37836 |
21.31 |
| 2026-06-19 12:00 |
07:43:59.90 |
+14:35:02.8 |
HIP 37836 |
20.50 |
| 2026-06-20 00:00 |
07:44:03.28 |
+14:34:55.1 |
HIP 37836 |
19.69 |
| 2026-06-20 12:00 |
07:44:06.68 |
+14:34:47.4 |
HIP 37836 |
18.88 |
| 2026-06-21 00:00 |
07:44:10.09 |
+14:34:39.6 |
HIP 37836 |
18.07 |
| 2026-06-21 12:00 |
07:44:13.51 |
+14:34:31.7 |
HIP 37836 |
17.25 |
| 2026-06-22 00:00 |
07:44:16.94 |
+14:34:23.7 |
HIP 37836 |
16.44 |