C/2009 F5 (McNaught)
| Parameter |
Value |
| Designation |
C/2009 F5 (McNaught) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2008-11-04T19:50:20.624640Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:30Z |
| Obs used |
444 |
| NEO |
- |
| M1 |
12.800 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2009-05-07.0000000 |
| e |
0.97199145 |
| q (au) |
2.245337 |
| a (au) |
80.166145 |
| i (deg) |
84.990355 |
| Ω (om, deg) |
219.064143 |
| ω (w, deg) |
297.366826 |
| M (ma, deg) |
0.251524 |
Magnitude
Scatter + Global Linear
$$
M_a = (14.104 + 2.537\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
14.104 |
| n |
2.537 |
| gf |
1.000 |
| gb |
-0.637 |
| 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) |
| 2026-02-03 00:00 |
18:40:23.25 |
+61:28:38.1 |
HIP 91673 |
10.11 |
| 2026-02-03 12:00 |
18:40:29.77 |
+61:29:10.3 |
HIP 91673 |
9.18 |
| 2026-02-04 00:00 |
18:40:36.26 |
+61:29:42.8 |
HIP 91673 |
8.26 |
| 2026-02-04 12:00 |
18:40:42.71 |
+61:30:15.6 |
HIP 91673 |
7.35 |
| 2026-02-05 00:00 |
18:40:49.13 |
+61:30:48.8 |
HIP 91673 |
6.44 |
| 2026-02-05 12:00 |
18:40:55.51 |
+61:31:22.3 |
HIP 91673 |
5.55 |
| 2026-02-06 00:00 |
18:41:01.86 |
+61:31:56.2 |
HIP 91673 |
4.69 |
| 2026-02-06 12:00 |
18:41:08.17 |
+61:32:30.5 |
HIP 91673 |
3.87 |
| 2026-02-07 00:00 |
18:41:14.44 |
+61:33:05.0 |
HIP 91673 |
3.13 |
| 2026-02-07 12:00 |
18:41:20.68 |
+61:33:40.0 |
HIP 91673 |
2.53 |
| 2026-02-08 00:00 |
18:41:26.88 |
+61:34:15.2 |
HIP 91673 |
2.20 |
| 2026-02-08 12:00 |
18:41:33.04 |
+61:34:50.8 |
HIP 91673 |
2.26 |
| 2026-02-09 00:00 |
18:41:39.17 |
+61:35:26.7 |
HIP 91673 |
2.67 |
| 2026-02-09 12:00 |
18:41:45.25 |
+61:36:03.0 |
HIP 91673 |
3.32 |
| 2026-02-10 00:00 |
18:41:51.30 |
+61:36:39.6 |
HIP 91673 |
4.09 |
| 2026-02-10 12:00 |
18:41:57.31 |
+61:37:16.5 |
HIP 91673 |
4.92 |
| 2026-02-11 00:00 |
18:42:03.28 |
+61:37:53.7 |
HIP 91673 |
5.79 |
| 2026-02-11 12:00 |
18:42:09.21 |
+61:38:31.3 |
HIP 91673 |
6.68 |
| 2026-02-12 00:00 |
18:42:15.09 |
+61:39:09.2 |
HIP 91673 |
7.58 |
| 2026-02-12 12:00 |
18:42:20.94 |
+61:39:47.4 |
HIP 91673 |
8.50 |
| 2026-02-13 00:00 |
18:42:26.75 |
+61:40:25.9 |
HIP 91673 |
9.42 |
| 2026-02-13 12:00 |
18:42:32.51 |
+61:41:04.7 |
HIP 91673 |
10.34 |
| 2026-02-14 00:00 |
18:42:38.23 |
+61:41:43.9 |
HIP 91673 |
11.27 |
| 2026-02-14 12:00 |
18:42:43.91 |
+61:42:23.3 |
HIP 91673 |
12.20 |
| 2026-02-15 00:00 |
18:42:49.54 |
+61:43:03.1 |
HIP 91673 |
13.14 |
| 2026-02-15 12:00 |
18:42:55.13 |
+61:43:43.1 |
HIP 91673 |
14.07 |
| 2026-02-16 00:00 |
18:43:00.68 |
+61:44:23.5 |
HIP 91673 |
15.01 |
| 2026-02-16 12:00 |
18:43:06.19 |
+61:45:04.1 |
HIP 91921 |
14.32 |
| 2026-02-17 00:00 |
18:43:11.64 |
+61:45:45.1 |
HIP 91921 |
13.38 |
| 2026-02-17 12:00 |
18:43:17.06 |
+61:46:26.3 |
HIP 91921 |
12.45 |
| 2026-02-18 00:00 |
18:43:22.43 |
+61:47:07.8 |
HIP 91921 |
11.51 |
| 2026-02-18 12:00 |
18:43:27.75 |
+61:47:49.6 |
HIP 91921 |
10.58 |
| 2026-02-19 00:00 |
18:43:33.02 |
+61:48:31.7 |
HIP 91921 |
9.64 |
| 2026-02-19 12:00 |
18:43:38.25 |
+61:49:14.1 |
HIP 91921 |
8.71 |
| 2026-02-20 00:00 |
18:43:43.43 |
+61:49:56.7 |
HIP 91921 |
7.78 |
| 2026-02-20 12:00 |
18:43:48.57 |
+61:50:39.6 |
HIP 91921 |
6.84 |
| 2026-02-21 00:00 |
18:43:53.66 |
+61:51:22.8 |
HIP 91921 |
5.91 |
| 2026-02-21 12:00 |
18:43:58.69 |
+61:52:06.3 |
HIP 91921 |
4.98 |
| 2026-02-22 00:00 |
18:44:03.68 |
+61:52:50.0 |
HIP 91921 |
4.05 |
| 2026-02-22 12:00 |
18:44:08.62 |
+61:53:33.9 |
HIP 91921 |
3.13 |
| 2026-02-23 00:00 |
18:44:13.52 |
+61:54:18.2 |
HIP 91921 |
2.21 |
| 2026-02-23 12:00 |
18:44:18.36 |
+61:55:02.7 |
HIP 91921 |
1.32 |
| 2026-02-24 00:00 |
18:44:23.15 |
+61:55:47.4 |
HIP 91921 |
0.58 |