| Parameter |
Value |
| Designation |
C/2007 M2 (Catalina) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2008-12-08T13:33:39.214080Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:09Z |
| Obs used |
432 |
| NEO |
- |
| M1 |
11.900 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2008-05-25.0000000 |
| e |
0.99933270 |
| q (au) |
3.541046 |
| a (au) |
5306.561037 |
| i (deg) |
80.945662 |
| Ω (om, deg) |
357.282850 |
| ω (w, deg) |
220.668951 |
| M (ma, deg) |
359.999496 |
Magnitude
Scatter + Global Linear
$$
M_a = (14.582 + 2.142\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
14.582 |
| n |
2.142 |
| gf |
1.000 |
| gb |
-0.776 |
| 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) |
| 2026-07-29 00:00 |
23:51:08.04 |
+03:04:06.9 |
HIP 117683 |
14.94 |
| 2026-07-29 12:00 |
23:51:06.00 |
+03:04:00.7 |
HIP 117683 |
15.31 |
| 2026-07-30 00:00 |
23:51:03.94 |
+03:03:54.5 |
HIP 117683 |
15.69 |
| 2026-07-30 12:00 |
23:51:01.87 |
+03:03:48.1 |
HIP 117683 |
16.09 |
| 2026-07-31 00:00 |
23:50:59.77 |
+03:03:41.5 |
HIP 117683 |
16.49 |
| 2026-07-31 12:00 |
23:50:57.65 |
+03:03:34.8 |
HIP 117683 |
16.91 |
| 2026-08-01 00:00 |
23:50:55.50 |
+03:03:27.9 |
HIP 117526 |
16.55 |
| 2026-08-01 12:00 |
23:50:53.34 |
+03:03:20.8 |
HIP 117526 |
16.07 |
| 2026-08-02 00:00 |
23:50:51.16 |
+03:03:13.7 |
HIP 117526 |
15.59 |
| 2026-08-02 12:00 |
23:50:48.96 |
+03:03:06.3 |
HIP 117526 |
15.10 |
| 2026-08-03 00:00 |
23:50:46.73 |
+03:02:58.8 |
HIP 117526 |
14.62 |
| 2026-08-03 12:00 |
23:50:44.49 |
+03:02:51.2 |
HIP 117526 |
14.14 |
| 2026-08-04 00:00 |
23:50:42.23 |
+03:02:43.4 |
HIP 117526 |
13.66 |
| 2026-08-04 12:00 |
23:50:39.95 |
+03:02:35.5 |
HIP 117526 |
13.18 |
| 2026-08-05 00:00 |
23:50:37.64 |
+03:02:27.4 |
HIP 117526 |
12.71 |
| 2026-08-05 12:00 |
23:50:35.32 |
+03:02:19.2 |
HIP 117526 |
12.24 |
| 2026-08-06 00:00 |
23:50:32.98 |
+03:02:10.8 |
HIP 117526 |
11.78 |
| 2026-08-06 12:00 |
23:50:30.62 |
+03:02:02.3 |
HIP 117526 |
11.33 |
| 2026-08-07 00:00 |
23:50:28.24 |
+03:01:53.7 |
HIP 117526 |
10.89 |
| 2026-08-07 12:00 |
23:50:25.84 |
+03:01:44.9 |
HIP 117526 |
10.46 |
| 2026-08-08 00:00 |
23:50:23.42 |
+03:01:35.9 |
HIP 117526 |
10.05 |
| 2026-08-08 12:00 |
23:50:20.99 |
+03:01:26.8 |
HIP 117526 |
9.65 |
| 2026-08-09 00:00 |
23:50:18.53 |
+03:01:17.6 |
HIP 117526 |
9.28 |
| 2026-08-09 12:00 |
23:50:16.06 |
+03:01:08.2 |
HIP 117526 |
8.93 |
| 2026-08-10 00:00 |
23:50:13.57 |
+03:00:58.7 |
HIP 117526 |
8.62 |
| 2026-08-10 12:00 |
23:50:11.06 |
+03:00:49.0 |
HIP 117526 |
8.33 |
| 2026-08-11 00:00 |
23:50:08.53 |
+03:00:39.3 |
HIP 117526 |
8.09 |
| 2026-08-11 12:00 |
23:50:05.99 |
+03:00:29.3 |
HIP 117526 |
7.89 |
| 2026-08-12 00:00 |
23:50:03.43 |
+03:00:19.3 |
HIP 117526 |
7.73 |
| 2026-08-12 12:00 |
23:50:00.85 |
+03:00:09.1 |
HIP 117526 |
7.64 |
| 2026-08-13 00:00 |
23:49:58.25 |
+02:59:58.7 |
HIP 117526 |
7.59 |
| 2026-08-13 12:00 |
23:49:55.64 |
+02:59:48.3 |
HIP 117526 |
7.61 |
| 2026-08-14 00:00 |
23:49:53.01 |
+02:59:37.7 |
HIP 117526 |
7.68 |
| 2026-08-14 12:00 |
23:49:50.36 |
+02:59:27.0 |
HIP 117526 |
7.82 |
| 2026-08-15 00:00 |
23:49:47.70 |
+02:59:16.1 |
HIP 117526 |
8.01 |
| 2026-08-15 12:00 |
23:49:45.02 |
+02:59:05.1 |
HIP 117526 |
8.25 |
| 2026-08-16 00:00 |
23:49:42.33 |
+02:58:54.0 |
HIP 117526 |
8.55 |
| 2026-08-16 12:00 |
23:49:39.62 |
+02:58:42.8 |
HIP 117526 |
8.89 |
| 2026-08-17 00:00 |
23:49:36.89 |
+02:58:31.4 |
HIP 117526 |
9.27 |
| 2026-08-17 12:00 |
23:49:34.15 |
+02:58:19.9 |
HIP 117526 |
9.69 |
| 2026-08-18 00:00 |
23:49:31.40 |
+02:58:08.3 |
HIP 117526 |
10.15 |
| 2026-08-18 12:00 |
23:49:28.63 |
+02:57:56.6 |
HIP 117526 |
10.64 |
| 2026-08-19 00:00 |
23:49:25.85 |
+02:57:44.7 |
HIP 117526 |
11.15 |