| 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) |
| 2026-05-12 00:00 |
10:07:02.61 |
+14:44:17.9 |
HIP 49623 |
26.69 |
| 2026-05-12 12:00 |
10:07:01.64 |
+14:44:15.6 |
HIP 49623 |
26.80 |
| 2026-05-13 00:00 |
10:07:00.70 |
+14:44:13.2 |
HIP 49623 |
26.92 |
| 2026-05-13 12:00 |
10:06:59.79 |
+14:44:10.6 |
HIP 49623 |
27.03 |
| 2026-05-14 00:00 |
10:06:58.91 |
+14:44:07.9 |
HIP 49623 |
27.15 |
| 2026-05-14 12:00 |
10:06:58.06 |
+14:44:05.0 |
HIP 49623 |
27.27 |
| 2026-05-15 00:00 |
10:06:57.24 |
+14:44:01.9 |
HIP 49623 |
27.39 |
| 2026-05-15 12:00 |
10:06:56.46 |
+14:43:58.7 |
HIP 49623 |
27.51 |
| 2026-05-16 00:00 |
10:06:55.70 |
+14:43:55.3 |
HIP 49623 |
27.63 |
| 2026-05-16 12:00 |
10:06:54.97 |
+14:43:51.7 |
HIP 49623 |
27.76 |
| 2026-05-17 00:00 |
10:06:54.28 |
+14:43:48.0 |
HIP 49623 |
27.88 |
| 2026-05-17 12:00 |
10:06:53.61 |
+14:43:44.1 |
HIP 49623 |
28.00 |
| 2026-05-18 00:00 |
10:06:52.98 |
+14:43:40.1 |
HIP 49623 |
28.12 |
| 2026-05-18 12:00 |
10:06:52.37 |
+14:43:35.9 |
HIP 49623 |
28.25 |
| 2026-05-19 00:00 |
10:06:51.80 |
+14:43:31.5 |
HIP 49623 |
28.37 |
| 2026-05-19 12:00 |
10:06:51.25 |
+14:43:27.0 |
HIP 49623 |
28.49 |
| 2026-05-20 00:00 |
10:06:50.74 |
+14:43:22.3 |
HIP 49623 |
28.61 |
| 2026-05-20 12:00 |
10:06:50.26 |
+14:43:17.5 |
HIP 49623 |
28.74 |
| 2026-05-21 00:00 |
10:06:49.80 |
+14:43:12.5 |
HIP 49623 |
28.86 |
| 2026-05-21 12:00 |
10:06:49.38 |
+14:43:07.3 |
HIP 49623 |
28.98 |
| 2026-05-22 00:00 |
10:06:48.99 |
+14:43:02.0 |
HIP 49623 |
29.10 |
| 2026-05-22 12:00 |
10:06:48.62 |
+14:42:56.5 |
HIP 49623 |
29.22 |
| 2026-05-23 00:00 |
10:06:48.29 |
+14:42:50.9 |
HIP 49623 |
29.34 |
| 2026-05-23 12:00 |
10:06:47.99 |
+14:42:45.1 |
HIP 49623 |
29.45 |
| 2026-05-24 00:00 |
10:06:47.71 |
+14:42:39.1 |
HIP 49623 |
29.57 |
| 2026-05-24 12:00 |
10:06:47.47 |
+14:42:33.0 |
HIP 49623 |
29.69 |
| 2026-05-25 00:00 |
10:06:47.26 |
+14:42:26.8 |
HIP 49623 |
29.81 |
| 2026-05-25 12:00 |
10:06:47.07 |
+14:42:20.4 |
HIP 49623 |
29.92 |
| 2026-05-26 00:00 |
10:06:46.92 |
+14:42:13.8 |
HIP 49623 |
30.04 |
| 2026-05-26 12:00 |
10:06:46.79 |
+14:42:07.1 |
HIP 49623 |
30.15 |
| 2026-05-27 00:00 |
10:06:46.70 |
+14:42:00.2 |
HIP 49623 |
30.26 |
| 2026-05-27 12:00 |
10:06:46.63 |
+14:41:53.2 |
HIP 49623 |
30.38 |
| 2026-05-28 00:00 |
10:06:46.59 |
+14:41:46.0 |
HIP 49623 |
30.49 |
| 2026-05-28 12:00 |
10:06:46.58 |
+14:41:38.7 |
HIP 49623 |
30.60 |
| 2026-05-29 00:00 |
10:06:46.60 |
+14:41:31.3 |
HIP 49623 |
30.71 |
| 2026-05-29 12:00 |
10:06:46.65 |
+14:41:23.6 |
HIP 49623 |
30.82 |
| 2026-05-30 00:00 |
10:06:46.73 |
+14:41:15.9 |
HIP 49623 |
30.93 |
| 2026-05-30 12:00 |
10:06:46.84 |
+14:41:08.0 |
HIP 49623 |
31.04 |
| 2026-05-31 00:00 |
10:06:46.98 |
+14:40:59.9 |
HIP 49623 |
31.15 |
| 2026-05-31 12:00 |
10:06:47.14 |
+14:40:51.7 |
HIP 49623 |
31.26 |
| 2026-06-01 00:00 |
10:06:47.34 |
+14:40:43.3 |
HIP 49623 |
31.37 |
| 2026-06-01 12:00 |
10:06:47.56 |
+14:40:34.8 |
HIP 49551 |
31.31 |
| 2026-06-02 00:00 |
10:06:47.81 |
+14:40:26.2 |
HIP 49551 |
31.16 |