| Parameter |
Value |
| Designation |
P/2013 J2 (McNaught) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2013-08-22T23:57:25.464960Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:35Z |
| Obs used |
1606 |
| NEO |
- |
| M1 |
12.800 |
| K1 |
7.250 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2013-09-18.0000000 |
| e |
0.65614970 |
| q (au) |
2.147830 |
| a (au) |
6.246411 |
| i (deg) |
15.495560 |
| Ω (om, deg) |
289.393509 |
| ω (w, deg) |
37.889335 |
| M (ma, deg) |
1.641578 |
Magnitude
Scatter + Global Linear
$$
M_a = (12.547 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
12.547 |
| n |
2.000 |
| gf |
0.999 |
| gb |
-0.947 |
| 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 |
11:32:28.07 |
-14:36:23.2 |
HIP 56218 |
27.42 |
| 2026-06-01 12:00 |
11:32:28.14 |
-14:35:16.4 |
HIP 56218 |
26.42 |
| 2026-06-02 00:00 |
11:32:28.35 |
-14:34:10.3 |
HIP 56218 |
25.46 |
| 2026-06-02 12:00 |
11:32:28.69 |
-14:33:05.1 |
HIP 56218 |
24.54 |
| 2026-06-03 00:00 |
11:32:29.16 |
-14:32:00.6 |
HIP 56218 |
23.66 |
| 2026-06-03 12:00 |
11:32:29.78 |
-14:30:56.9 |
HIP 56218 |
22.83 |
| 2026-06-04 00:00 |
11:32:30.53 |
-14:29:54.1 |
HIP 56218 |
22.05 |
| 2026-06-04 12:00 |
11:32:31.42 |
-14:28:52.1 |
HIP 56218 |
21.32 |
| 2026-06-05 00:00 |
11:32:32.44 |
-14:27:50.8 |
HIP 56218 |
20.66 |
| 2026-06-05 12:00 |
11:32:33.60 |
-14:26:50.4 |
HIP 56218 |
20.05 |
| 2026-06-06 00:00 |
11:32:34.89 |
-14:25:50.8 |
HIP 56218 |
19.52 |
| 2026-06-06 12:00 |
11:32:36.32 |
-14:24:52.1 |
HIP 56218 |
19.06 |
| 2026-06-07 00:00 |
11:32:37.89 |
-14:23:54.2 |
HIP 56218 |
18.69 |
| 2026-06-07 12:00 |
11:32:39.59 |
-14:22:57.1 |
HIP 56218 |
18.40 |
| 2026-06-08 00:00 |
11:32:41.42 |
-14:22:00.9 |
HIP 56218 |
18.19 |
| 2026-06-08 12:00 |
11:32:43.39 |
-14:21:05.5 |
HIP 56218 |
18.09 |
| 2026-06-09 00:00 |
11:32:45.50 |
-14:20:11.0 |
HIP 56218 |
18.07 |
| 2026-06-09 12:00 |
11:32:47.73 |
-14:19:17.3 |
HIP 56218 |
18.15 |
| 2026-06-10 00:00 |
11:32:50.11 |
-14:18:24.5 |
HIP 56218 |
18.33 |
| 2026-06-10 12:00 |
11:32:52.61 |
-14:17:32.6 |
HIP 56218 |
18.60 |
| 2026-06-11 00:00 |
11:32:55.25 |
-14:16:41.5 |
HIP 56218 |
18.96 |
| 2026-06-11 12:00 |
11:32:58.03 |
-14:15:51.3 |
HIP 56218 |
19.40 |
| 2026-06-12 00:00 |
11:33:00.94 |
-14:15:02.0 |
HIP 56218 |
19.93 |
| 2026-06-12 12:00 |
11:33:03.98 |
-14:14:13.5 |
HIP 56218 |
20.54 |
| 2026-06-13 00:00 |
11:33:07.15 |
-14:13:26.0 |
HIP 56218 |
21.22 |
| 2026-06-13 12:00 |
11:33:10.45 |
-14:12:39.3 |
HIP 56218 |
21.97 |
| 2026-06-14 00:00 |
11:33:13.89 |
-14:11:53.6 |
HIP 56218 |
22.77 |
| 2026-06-14 12:00 |
11:33:17.46 |
-14:11:08.7 |
HIP 56218 |
23.64 |
| 2026-06-15 00:00 |
11:33:21.16 |
-14:10:24.8 |
HIP 56218 |
24.56 |
| 2026-06-15 12:00 |
11:33:24.99 |
-14:09:41.7 |
HIP 56218 |
25.53 |
| 2026-06-16 00:00 |
11:33:28.95 |
-14:08:59.6 |
HIP 56450 |
25.05 |
| 2026-06-16 12:00 |
11:33:33.05 |
-14:08:18.4 |
HIP 56450 |
23.92 |
| 2026-06-17 00:00 |
11:33:37.27 |
-14:07:38.0 |
HIP 56450 |
22.80 |
| 2026-06-17 12:00 |
11:33:41.62 |
-14:06:58.6 |
HIP 56450 |
21.68 |
| 2026-06-18 00:00 |
11:33:46.10 |
-14:06:20.1 |
HIP 56450 |
20.58 |
| 2026-06-18 12:00 |
11:33:50.71 |
-14:05:42.6 |
HIP 56450 |
19.50 |
| 2026-06-19 00:00 |
11:33:55.45 |
-14:05:05.9 |
HIP 56450 |
18.44 |
| 2026-06-19 12:00 |
11:34:00.31 |
-14:04:30.2 |
HIP 56450 |
17.41 |
| 2026-06-20 00:00 |
11:34:05.30 |
-14:03:55.4 |
HIP 56450 |
16.44 |
| 2026-06-20 12:00 |
11:34:10.42 |
-14:03:21.6 |
HIP 56450 |
15.52 |
| 2026-06-21 00:00 |
11:34:15.66 |
-14:02:48.6 |
HIP 56450 |
14.68 |
| 2026-06-21 12:00 |
11:34:21.03 |
-14:02:16.6 |
HIP 56450 |
13.94 |
| 2026-06-22 00:00 |
11:34:26.52 |
-14:01:45.5 |
HIP 56450 |
13.33 |