| Parameter |
Value |
| Designation |
P/2009 Q5 (McNaught) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2009-09-08T13:50:29.091840Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:34Z |
| Obs used |
331 |
| NEO |
- |
| M1 |
13.100 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2009-10-09.0000000 |
| e |
0.60905285 |
| q (au) |
2.918512 |
| a (au) |
7.465233 |
| i (deg) |
40.904822 |
| Ω (om, deg) |
160.139864 |
| ω (w, deg) |
209.274918 |
| M (ma, deg) |
1.470093 |
Magnitude
Scatter + Global Linear
$$
M_a = (12.633 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
12.633 |
| n |
2.000 |
| gf |
0.978 |
| gb |
-1.000 |
| k |
0.999 |
| δ90 |
9.962 |
| 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
Finding Chart
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
16:13:26.66 |
+21:45:49.7 |
HIP 79472 |
12.63 |
| 2026-03-26 12:00 |
16:13:23.38 |
+21:48:17.2 |
HIP 79472 |
14.76 |
| 2026-03-27 00:00 |
16:13:19.99 |
+21:50:44.5 |
HIP 79472 |
17.00 |
| 2026-03-27 12:00 |
16:13:16.46 |
+21:53:11.6 |
HIP 79472 |
19.32 |
| 2026-03-28 00:00 |
16:13:12.81 |
+21:55:38.4 |
HIP 79446 |
21.17 |
| 2026-03-28 12:00 |
16:13:09.02 |
+21:58:05.0 |
HIP 79446 |
18.58 |
| 2026-03-29 00:00 |
16:13:05.12 |
+22:00:31.3 |
HIP 79446 |
15.99 |
| 2026-03-29 12:00 |
16:13:01.09 |
+22:02:57.3 |
HIP 79446 |
13.40 |
| 2026-03-30 00:00 |
16:12:56.93 |
+22:05:23.0 |
HIP 79446 |
10.82 |
| 2026-03-30 12:00 |
16:12:52.65 |
+22:07:48.3 |
HIP 79446 |
8.26 |
| 2026-03-31 00:00 |
16:12:48.24 |
+22:10:13.4 |
HIP 79446 |
5.76 |
| 2026-03-31 12:00 |
16:12:43.71 |
+22:12:38.1 |
HIP 79446 |
3.46 |
| 2026-04-01 00:00 |
16:12:39.05 |
+22:15:02.5 |
HIP 79446 |
2.17 |
| 2026-04-01 12:00 |
16:12:34.27 |
+22:17:26.4 |
HIP 79446 |
3.39 |
| 2026-04-02 00:00 |
16:12:29.37 |
+22:19:50.0 |
HIP 79446 |
5.70 |
| 2026-04-02 12:00 |
16:12:24.34 |
+22:22:13.2 |
HIP 79446 |
8.22 |
| 2026-04-03 00:00 |
16:12:19.20 |
+22:24:36.0 |
HIP 79446 |
10.82 |
| 2026-04-03 12:00 |
16:12:13.93 |
+22:26:58.4 |
HIP 79446 |
13.46 |
| 2026-04-04 00:00 |
16:12:08.54 |
+22:29:20.3 |
HIP 79446 |
16.11 |
| 2026-04-04 12:00 |
16:12:03.02 |
+22:31:41.8 |
HIP 79446 |
18.78 |
| 2026-04-05 00:00 |
16:11:57.39 |
+22:34:02.8 |
HIP 79446 |
21.46 |
| 2026-04-05 12:00 |
16:11:51.64 |
+22:36:23.3 |
HIP 79446 |
24.15 |
| 2026-04-06 00:00 |
16:11:45.77 |
+22:38:43.4 |
HIP 79446 |
26.84 |
| 2026-04-06 12:00 |
16:11:39.78 |
+22:41:02.9 |
HIP 79412 |
28.88 |
| 2026-04-07 00:00 |
16:11:33.67 |
+22:43:21.9 |
HIP 79412 |
27.30 |
| 2026-04-07 12:00 |
16:11:27.44 |
+22:45:40.3 |
HIP 79412 |
25.93 |
| 2026-04-08 00:00 |
16:11:21.09 |
+22:47:58.3 |
HIP 79412 |
24.81 |
| 2026-04-08 12:00 |
16:11:14.63 |
+22:50:15.6 |
HIP 79412 |
23.97 |
| 2026-04-09 00:00 |
16:11:08.05 |
+22:52:32.3 |
HIP 79412 |
23.45 |
| 2026-04-09 12:00 |
16:11:01.36 |
+22:54:48.5 |
HIP 79412 |
23.27 |
| 2026-04-10 00:00 |
16:10:54.55 |
+22:57:04.0 |
HIP 79412 |
23.43 |
| 2026-04-10 12:00 |
16:10:47.62 |
+22:59:19.0 |
HIP 79412 |
23.94 |
| 2026-04-11 00:00 |
16:10:40.59 |
+23:01:33.2 |
HIP 79412 |
24.78 |
| 2026-04-11 12:00 |
16:10:33.44 |
+23:03:46.9 |
HIP 79412 |
25.91 |
| 2026-04-12 00:00 |
16:10:26.17 |
+23:05:59.8 |
HIP 79412 |
27.30 |
| 2026-04-12 12:00 |
16:10:18.80 |
+23:08:12.1 |
HIP 79349 |
28.16 |
| 2026-04-13 00:00 |
16:10:11.31 |
+23:10:23.6 |
HIP 79349 |
27.73 |
| 2026-04-13 12:00 |
16:10:03.72 |
+23:12:34.5 |
HIP 79349 |
27.60 |
| 2026-04-14 00:00 |
16:09:56.01 |
+23:14:44.6 |
HIP 79349 |
27.78 |
| 2026-04-14 12:00 |
16:09:48.20 |
+23:16:53.9 |
HIP 79349 |
28.27 |
| 2026-04-15 00:00 |
16:09:40.28 |
+23:19:02.5 |
HIP 79349 |
29.04 |
| 2026-04-15 12:00 |
16:09:32.25 |
+23:21:10.4 |
HIP 79349 |
30.09 |
| 2026-04-16 00:00 |
16:09:24.12 |
+23:23:17.4 |
HIP 79349 |
31.38 |