| Parameter |
Value |
| Designation |
C/2006 A2 (Catalina) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2005-05-20T02:43:40.612800Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:56Z |
| Obs used |
89 |
| NEO |
- |
| M1 |
12.600 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2006-03-18.0000000 |
| e |
0.99862239 |
| q (au) |
5.315949 |
| a (au) |
3858.814166 |
| i (deg) |
148.322579 |
| Ω (om, deg) |
233.225358 |
| ω (w, deg) |
141.018293 |
| M (ma, deg) |
0.001241 |
Magnitude
Scatter + Global Linear
$$
M_a = (14.845 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
14.845 |
| n |
2.000 |
| gf |
0.992 |
| gb |
-0.701 |
| k |
0.800 |
| δ90 |
9.994 |
| 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 |
22:01:27.01 |
-46:42:15.6 |
HIP 108624 |
18.93 |
| 2026-07-29 12:00 |
22:01:22.68 |
-46:42:39.1 |
HIP 108624 |
18.18 |
| 2026-07-30 00:00 |
22:01:18.35 |
-46:43:02.4 |
HIP 108624 |
17.44 |
| 2026-07-30 12:00 |
22:01:14.00 |
-46:43:25.5 |
HIP 108624 |
16.71 |
| 2026-07-31 00:00 |
22:01:09.63 |
-46:43:48.5 |
HIP 108624 |
15.99 |
| 2026-07-31 12:00 |
22:01:05.25 |
-46:44:11.2 |
HIP 108624 |
15.29 |
| 2026-08-01 00:00 |
22:01:00.86 |
-46:44:33.8 |
HIP 108624 |
14.60 |
| 2026-08-01 12:00 |
22:00:56.46 |
-46:44:56.2 |
HIP 108624 |
13.93 |
| 2026-08-02 00:00 |
22:00:52.04 |
-46:45:18.4 |
HIP 108624 |
13.28 |
| 2026-08-02 12:00 |
22:00:47.61 |
-46:45:40.5 |
HIP 108624 |
12.66 |
| 2026-08-03 00:00 |
22:00:43.17 |
-46:46:02.3 |
HIP 108624 |
12.06 |
| 2026-08-03 12:00 |
22:00:38.72 |
-46:46:23.9 |
HIP 108624 |
11.50 |
| 2026-08-04 00:00 |
22:00:34.25 |
-46:46:45.4 |
HIP 108624 |
10.98 |
| 2026-08-04 12:00 |
22:00:29.78 |
-46:47:06.7 |
HIP 108624 |
10.50 |
| 2026-08-05 00:00 |
22:00:25.29 |
-46:47:27.7 |
HIP 108624 |
10.08 |
| 2026-08-05 12:00 |
22:00:20.79 |
-46:47:48.6 |
HIP 108624 |
9.71 |
| 2026-08-06 00:00 |
22:00:16.29 |
-46:48:09.3 |
HIP 108624 |
9.40 |
| 2026-08-06 12:00 |
22:00:11.77 |
-46:48:29.7 |
HIP 108624 |
9.17 |
| 2026-08-07 00:00 |
22:00:07.24 |
-46:48:50.0 |
HIP 108624 |
9.02 |
| 2026-08-07 12:00 |
22:00:02.71 |
-46:49:10.0 |
HIP 108624 |
8.94 |
| 2026-08-08 00:00 |
21:59:58.16 |
-46:49:29.9 |
HIP 108624 |
8.95 |
| 2026-08-08 12:00 |
21:59:53.61 |
-46:49:49.5 |
HIP 108523 |
8.75 |
| 2026-08-09 00:00 |
21:59:49.05 |
-46:50:09.0 |
HIP 108523 |
8.24 |
| 2026-08-09 12:00 |
21:59:44.48 |
-46:50:28.2 |
HIP 108523 |
7.78 |
| 2026-08-10 00:00 |
21:59:39.90 |
-46:50:47.2 |
HIP 108523 |
7.38 |
| 2026-08-10 12:00 |
21:59:35.31 |
-46:51:06.0 |
HIP 108523 |
7.06 |
| 2026-08-11 00:00 |
21:59:30.72 |
-46:51:24.6 |
HIP 108523 |
6.83 |
| 2026-08-11 12:00 |
21:59:26.13 |
-46:51:43.0 |
HIP 108523 |
6.69 |
| 2026-08-12 00:00 |
21:59:21.52 |
-46:52:01.1 |
HIP 108523 |
6.65 |
| 2026-08-12 12:00 |
21:59:16.91 |
-46:52:19.1 |
HIP 108523 |
6.72 |
| 2026-08-13 00:00 |
21:59:12.30 |
-46:52:36.8 |
HIP 108523 |
6.88 |
| 2026-08-13 12:00 |
21:59:07.67 |
-46:52:54.3 |
HIP 108523 |
7.14 |
| 2026-08-14 00:00 |
21:59:03.05 |
-46:53:11.5 |
HIP 108523 |
7.48 |
| 2026-08-14 12:00 |
21:58:58.42 |
-46:53:28.5 |
HIP 108523 |
7.89 |
| 2026-08-15 00:00 |
21:58:53.79 |
-46:53:45.4 |
HIP 108523 |
8.37 |
| 2026-08-15 12:00 |
21:58:49.15 |
-46:54:01.9 |
HIP 108523 |
8.89 |
| 2026-08-16 00:00 |
21:58:44.51 |
-46:54:18.3 |
HIP 108523 |
9.46 |
| 2026-08-16 12:00 |
21:58:39.86 |
-46:54:34.4 |
HIP 108523 |
10.06 |
| 2026-08-17 00:00 |
21:58:35.22 |
-46:54:50.3 |
HIP 108523 |
10.69 |
| 2026-08-17 12:00 |
21:58:30.57 |
-46:55:05.9 |
HIP 108523 |
11.35 |
| 2026-08-18 00:00 |
21:58:25.92 |
-46:55:21.4 |
HIP 108523 |
12.02 |
| 2026-08-18 12:00 |
21:58:21.27 |
-46:55:36.5 |
HIP 108523 |
12.71 |
| 2026-08-19 00:00 |
21:58:16.62 |
-46:55:51.5 |
HIP 108523 |
13.41 |