| 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 |
-0.502 |
| 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) |
| 2026-03-26 00:00 |
07:39:52.56 |
+14:34:44.1 |
HIP 37282 |
10.44 |
| 2026-03-26 12:00 |
07:39:51.49 |
+14:34:51.4 |
HIP 37282 |
10.33 |
| 2026-03-27 00:00 |
07:39:50.44 |
+14:34:58.6 |
HIP 37282 |
10.23 |
| 2026-03-27 12:00 |
07:39:49.43 |
+14:35:05.8 |
HIP 37282 |
10.14 |
| 2026-03-28 00:00 |
07:39:48.45 |
+14:35:12.9 |
HIP 37282 |
10.07 |
| 2026-03-28 12:00 |
07:39:47.50 |
+14:35:19.9 |
HIP 37282 |
10.00 |
| 2026-03-29 00:00 |
07:39:46.58 |
+14:35:26.9 |
HIP 37282 |
9.95 |
| 2026-03-29 12:00 |
07:39:45.70 |
+14:35:33.8 |
HIP 37282 |
9.90 |
| 2026-03-30 00:00 |
07:39:44.85 |
+14:35:40.7 |
HIP 37282 |
9.87 |
| 2026-03-30 12:00 |
07:39:44.03 |
+14:35:47.4 |
HIP 37282 |
9.84 |
| 2026-03-31 00:00 |
07:39:43.24 |
+14:35:54.1 |
HIP 37282 |
9.82 |
| 2026-03-31 12:00 |
07:39:42.49 |
+14:36:00.7 |
HIP 37282 |
9.81 |
| 2026-04-01 00:00 |
07:39:41.77 |
+14:36:07.3 |
HIP 37282 |
9.81 |
| 2026-04-01 12:00 |
07:39:41.08 |
+14:36:13.8 |
HIP 37282 |
9.82 |
| 2026-04-02 00:00 |
07:39:40.43 |
+14:36:20.2 |
HIP 37282 |
9.83 |
| 2026-04-02 12:00 |
07:39:39.81 |
+14:36:26.5 |
HIP 37282 |
9.85 |
| 2026-04-03 00:00 |
07:39:39.22 |
+14:36:32.8 |
HIP 37282 |
9.87 |
| 2026-04-03 12:00 |
07:39:38.66 |
+14:36:39.0 |
HIP 37282 |
9.90 |
| 2026-04-04 00:00 |
07:39:38.14 |
+14:36:45.1 |
HIP 37282 |
9.94 |
| 2026-04-04 12:00 |
07:39:37.65 |
+14:36:51.2 |
HIP 37282 |
9.98 |
| 2026-04-05 00:00 |
07:39:37.19 |
+14:36:57.2 |
HIP 37282 |
10.02 |
| 2026-04-05 12:00 |
07:39:36.77 |
+14:37:03.1 |
HIP 37282 |
10.07 |
| 2026-04-06 00:00 |
07:39:36.37 |
+14:37:08.9 |
HIP 37282 |
10.13 |
| 2026-04-06 12:00 |
07:39:36.01 |
+14:37:14.6 |
HIP 37282 |
10.18 |
| 2026-04-07 00:00 |
07:39:35.69 |
+14:37:20.3 |
HIP 37282 |
10.24 |
| 2026-04-07 12:00 |
07:39:35.39 |
+14:37:25.9 |
HIP 37282 |
10.30 |
| 2026-04-08 00:00 |
07:39:35.13 |
+14:37:31.4 |
HIP 37282 |
10.37 |
| 2026-04-08 12:00 |
07:39:34.90 |
+14:37:36.9 |
HIP 37282 |
10.43 |
| 2026-04-09 00:00 |
07:39:34.71 |
+14:37:42.2 |
HIP 37282 |
10.50 |
| 2026-04-09 12:00 |
07:39:34.54 |
+14:37:47.5 |
HIP 37282 |
10.57 |
| 2026-04-10 00:00 |
07:39:34.41 |
+14:37:52.7 |
HIP 37282 |
10.64 |
| 2026-04-10 12:00 |
07:39:34.32 |
+14:37:57.8 |
HIP 37282 |
10.72 |
| 2026-04-11 00:00 |
07:39:34.25 |
+14:38:02.9 |
HIP 37282 |
10.79 |
| 2026-04-11 12:00 |
07:39:34.22 |
+14:38:07.8 |
HIP 37282 |
10.87 |
| 2026-04-12 00:00 |
07:39:34.22 |
+14:38:12.7 |
HIP 37282 |
10.94 |
| 2026-04-12 12:00 |
07:39:34.26 |
+14:38:17.5 |
HIP 37282 |
11.02 |
| 2026-04-13 00:00 |
07:39:34.32 |
+14:38:22.2 |
HIP 37282 |
11.10 |
| 2026-04-13 12:00 |
07:39:34.42 |
+14:38:26.9 |
HIP 37282 |
11.18 |
| 2026-04-14 00:00 |
07:39:34.55 |
+14:38:31.4 |
HIP 37282 |
11.27 |
| 2026-04-14 12:00 |
07:39:34.72 |
+14:38:35.9 |
HIP 37282 |
11.35 |
| 2026-04-15 00:00 |
07:39:34.92 |
+14:38:40.3 |
HIP 37282 |
11.43 |
| 2026-04-15 12:00 |
07:39:35.15 |
+14:38:44.6 |
HIP 37282 |
11.52 |
| 2026-04-16 00:00 |
07:39:35.41 |
+14:38:48.8 |
HIP 37282 |
11.60 |