| Parameter |
Value |
| Designation |
C/2011 L2 (McNaught) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2011-11-01T06:33:18.060480Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:51Z |
| Obs used |
57 |
| NEO |
- |
| M1 |
11.800 |
| K1 |
13.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2011-09-08.0000000 |
| e |
1.00177257 |
| q (au) |
1.943449 |
| a (au) |
-1096.399619 |
| i (deg) |
104.257426 |
| Ω (om, deg) |
131.347725 |
| ω (w, deg) |
257.028128 |
| M (ma, deg) |
-0.001473 |
Magnitude
Scatter + Global Linear
$$
M_a = (18.228 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
18.228 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-1.000 |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-06-01 00:00 |
08:52:13.91 |
+65:18:24.8 |
HIP 43399 |
28.91 |
| 2026-06-01 12:00 |
08:52:18.05 |
+65:17:48.4 |
HIP 43399 |
28.54 |
| 2026-06-02 00:00 |
08:52:22.24 |
+65:17:12.1 |
HIP 43399 |
28.18 |
| 2026-06-02 12:00 |
08:52:26.49 |
+65:16:36.0 |
HIP 43399 |
27.84 |
| 2026-06-03 00:00 |
08:52:30.80 |
+65:16:00.0 |
HIP 43399 |
27.53 |
| 2026-06-03 12:00 |
08:52:35.16 |
+65:15:24.0 |
HIP 43399 |
27.23 |
| 2026-06-04 00:00 |
08:52:39.57 |
+65:14:48.2 |
HIP 43399 |
26.96 |
| 2026-06-04 12:00 |
08:52:44.04 |
+65:14:12.4 |
HIP 43399 |
26.72 |
| 2026-06-05 00:00 |
08:52:48.56 |
+65:13:36.8 |
HIP 43399 |
26.49 |
| 2026-06-05 12:00 |
08:52:53.14 |
+65:13:01.4 |
HIP 43399 |
26.30 |
| 2026-06-06 00:00 |
08:52:57.77 |
+65:12:26.0 |
HIP 43399 |
26.13 |
| 2026-06-06 12:00 |
08:53:02.46 |
+65:11:50.8 |
HIP 43399 |
25.98 |
| 2026-06-07 00:00 |
08:53:07.19 |
+65:11:15.6 |
HIP 43399 |
25.86 |
| 2026-06-07 12:00 |
08:53:11.98 |
+65:10:40.7 |
HIP 43399 |
25.77 |
| 2026-06-08 00:00 |
08:53:16.82 |
+65:10:05.8 |
HIP 43399 |
25.71 |
| 2026-06-08 12:00 |
08:53:21.71 |
+65:09:31.1 |
HIP 43399 |
25.68 |
| 2026-06-09 00:00 |
08:53:26.66 |
+65:08:56.5 |
HIP 43399 |
25.68 |
| 2026-06-09 12:00 |
08:53:31.65 |
+65:08:22.0 |
HIP 43399 |
25.71 |
| 2026-06-10 00:00 |
08:53:36.70 |
+65:07:47.7 |
HIP 43910 |
25.07 |
| 2026-06-10 12:00 |
08:53:41.79 |
+65:07:13.5 |
HIP 43910 |
24.30 |
| 2026-06-11 00:00 |
08:53:46.94 |
+65:06:39.5 |
HIP 43910 |
23.52 |
| 2026-06-11 12:00 |
08:53:52.13 |
+65:06:05.6 |
HIP 43910 |
22.74 |
| 2026-06-12 00:00 |
08:53:57.37 |
+65:05:31.9 |
HIP 43910 |
21.96 |
| 2026-06-12 12:00 |
08:54:02.66 |
+65:04:58.3 |
HIP 43910 |
21.18 |
| 2026-06-13 00:00 |
08:54:08.00 |
+65:04:24.8 |
HIP 43910 |
20.40 |
| 2026-06-13 12:00 |
08:54:13.39 |
+65:03:51.6 |
HIP 43910 |
19.61 |
| 2026-06-14 00:00 |
08:54:18.83 |
+65:03:18.4 |
HIP 43910 |
18.83 |
| 2026-06-14 12:00 |
08:54:24.31 |
+65:02:45.5 |
HIP 43910 |
18.04 |
| 2026-06-15 00:00 |
08:54:29.84 |
+65:02:12.6 |
HIP 43910 |
17.24 |
| 2026-06-15 12:00 |
08:54:35.41 |
+65:01:40.0 |
HIP 43910 |
16.45 |
| 2026-06-16 00:00 |
08:54:41.03 |
+65:01:07.5 |
HIP 43910 |
15.66 |
| 2026-06-16 12:00 |
08:54:46.69 |
+65:00:35.2 |
HIP 43910 |
14.86 |
| 2026-06-17 00:00 |
08:54:52.40 |
+65:00:03.1 |
HIP 43910 |
14.06 |
| 2026-06-17 12:00 |
08:54:58.16 |
+64:59:31.1 |
HIP 43910 |
13.26 |
| 2026-06-18 00:00 |
08:55:03.95 |
+64:58:59.3 |
HIP 43910 |
12.46 |
| 2026-06-18 12:00 |
08:55:09.79 |
+64:58:27.7 |
HIP 43910 |
11.65 |
| 2026-06-19 00:00 |
08:55:15.68 |
+64:57:56.3 |
HIP 43910 |
10.85 |
| 2026-06-19 12:00 |
08:55:21.60 |
+64:57:25.0 |
HIP 43910 |
10.04 |
| 2026-06-20 00:00 |
08:55:27.57 |
+64:56:53.9 |
HIP 43910 |
9.24 |
| 2026-06-20 12:00 |
08:55:33.58 |
+64:56:23.0 |
HIP 43910 |
8.43 |
| 2026-06-21 00:00 |
08:55:39.63 |
+64:55:52.3 |
HIP 43910 |
7.62 |
| 2026-06-21 12:00 |
08:55:45.72 |
+64:55:21.8 |
HIP 43910 |
6.81 |
| 2026-06-22 00:00 |
08:55:51.85 |
+64:54:51.5 |
HIP 43910 |
6.01 |