C/2007 M1 (McNaught)
| Parameter |
Value |
| Designation |
C/2007 M1 (McNaught) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2008-08-11T17:35:21.920640Z |
| Orbit solution date (soln_date, UTC) |
2022-07-06T03:12:21Z |
| Obs used |
232 |
| NEO |
- |
| M1 |
6.600 |
| K1 |
9.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2008-10-11.0000000 |
| e |
0.99520236 |
| q (au) |
7.474661 |
| a (au) |
1557.985505 |
| i (deg) |
139.721499 |
| Ω (om, deg) |
326.808769 |
| ω (w, deg) |
52.635857 |
| M (ma, deg) |
0.000966 |
Magnitude
Scatter + Global Linear
$$
M_a = (4.972 + 4.027\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
4.972 |
| n |
4.027 |
| gf |
0.993 |
| gb |
-1.000 |
| k |
1.000 |
| δ90 |
9.991 |
| 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 |
10:17:27.44 |
+14:07:06.4 |
HIP 50479 |
18.03 |
| 2026-02-03 12:00 |
10:17:23.46 |
+14:07:24.9 |
HIP 50479 |
18.98 |
| 2026-02-04 00:00 |
10:17:19.47 |
+14:07:43.5 |
HIP 50479 |
19.94 |
| 2026-02-04 12:00 |
10:17:15.47 |
+14:08:02.1 |
HIP 50479 |
20.91 |
| 2026-02-05 00:00 |
10:17:11.46 |
+14:08:20.7 |
HIP 50479 |
21.89 |
| 2026-02-05 12:00 |
10:17:07.44 |
+14:08:39.3 |
HIP 50479 |
22.87 |
| 2026-02-06 00:00 |
10:17:03.41 |
+14:08:58.0 |
HIP 50479 |
23.86 |
| 2026-02-06 12:00 |
10:16:59.37 |
+14:09:16.6 |
HIP 50479 |
24.85 |
| 2026-02-07 00:00 |
10:16:55.32 |
+14:09:35.3 |
HIP 50479 |
25.85 |
| 2026-02-07 12:00 |
10:16:51.27 |
+14:09:54.0 |
HIP 50333 |
26.32 |
| 2026-02-08 00:00 |
10:16:47.20 |
+14:10:12.7 |
HIP 50333 |
26.56 |
| 2026-02-08 12:00 |
10:16:43.13 |
+14:10:31.4 |
HIP 50333 |
26.83 |
| 2026-02-09 00:00 |
10:16:39.05 |
+14:10:50.1 |
HIP 50333 |
27.14 |
| 2026-02-09 12:00 |
10:16:34.97 |
+14:11:08.8 |
HIP 50333 |
27.48 |
| 2026-02-10 00:00 |
10:16:30.87 |
+14:11:27.6 |
HIP 50333 |
27.86 |
| 2026-02-10 12:00 |
10:16:26.77 |
+14:11:46.3 |
HIP 50333 |
28.27 |
| 2026-02-11 00:00 |
10:16:22.67 |
+14:12:05.0 |
HIP 50333 |
28.72 |
| 2026-02-11 12:00 |
10:16:18.55 |
+14:12:23.7 |
HIP 50333 |
29.19 |
| 2026-02-12 00:00 |
10:16:14.43 |
+14:12:42.4 |
HIP 50333 |
29.70 |
| 2026-02-12 12:00 |
10:16:10.31 |
+14:13:01.1 |
HIP 50333 |
30.23 |
| 2026-02-13 00:00 |
10:16:06.18 |
+14:13:19.9 |
HIP 50333 |
30.79 |
| 2026-02-13 12:00 |
10:16:02.05 |
+14:13:38.5 |
HIP 50333 |
31.38 |
| 2026-02-14 00:00 |
10:15:57.91 |
+14:13:57.2 |
HIP 50333 |
31.99 |
| 2026-02-14 12:00 |
10:15:53.77 |
+14:14:15.9 |
HIP 50333 |
32.62 |
| 2026-02-15 00:00 |
10:15:49.63 |
+14:14:34.6 |
HIP 50333 |
33.27 |
| 2026-02-15 12:00 |
10:15:45.48 |
+14:14:53.2 |
HIP 50333 |
33.94 |
| 2026-02-16 00:00 |
10:15:41.33 |
+14:15:11.8 |
HIP 50124 |
34.13 |
| 2026-02-16 12:00 |
10:15:37.17 |
+14:15:30.4 |
HIP 50124 |
33.60 |
| 2026-02-17 00:00 |
10:15:33.01 |
+14:15:49.0 |
HIP 50124 |
33.10 |
| 2026-02-17 12:00 |
10:15:28.85 |
+14:16:07.6 |
HIP 50124 |
32.62 |
| 2026-02-18 00:00 |
10:15:24.69 |
+14:16:26.1 |
HIP 50124 |
32.17 |
| 2026-02-18 12:00 |
10:15:20.53 |
+14:16:44.6 |
HIP 50124 |
31.75 |
| 2026-02-19 00:00 |
10:15:16.37 |
+14:17:03.1 |
HIP 50124 |
31.35 |
| 2026-02-19 12:00 |
10:15:12.20 |
+14:17:21.5 |
HIP 50124 |
30.99 |
| 2026-02-20 00:00 |
10:15:08.04 |
+14:17:39.9 |
HIP 50124 |
30.66 |
| 2026-02-20 12:00 |
10:15:03.88 |
+14:17:58.3 |
HIP 50124 |
30.36 |
| 2026-02-21 00:00 |
10:14:59.71 |
+14:18:16.6 |
HIP 50124 |
30.09 |
| 2026-02-21 12:00 |
10:14:55.55 |
+14:18:34.9 |
HIP 50124 |
29.86 |
| 2026-02-22 00:00 |
10:14:51.39 |
+14:18:53.1 |
HIP 50124 |
29.67 |
| 2026-02-22 12:00 |
10:14:47.22 |
+14:19:11.4 |
HIP 50124 |
29.51 |
| 2026-02-23 00:00 |
10:14:43.07 |
+14:19:29.5 |
HIP 50124 |
29.38 |
| 2026-02-23 12:00 |
10:14:38.91 |
+14:19:47.6 |
HIP 50124 |
29.29 |
| 2026-02-24 00:00 |
10:14:34.75 |
+14:20:05.7 |
HIP 50124 |
29.24 |