C/2005 N4 (Catalina)
| Parameter |
Value |
| Designation |
C/2005 N4 (Catalina) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2005-07-02T14:23:55.170240Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:51Z |
| Obs used |
206 |
| NEO |
- |
| M1 |
14.200 |
| K1 |
10.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2005-07-14.0000000 |
| e |
0.96061201 |
| q (au) |
2.303757 |
| a (au) |
58.488820 |
| i (deg) |
116.630292 |
| Ω (om, deg) |
64.036800 |
| ω (w, deg) |
136.545857 |
| M (ma, deg) |
0.025119 |
Magnitude
Scatter + Global Linear
$$
M_a = (15.381 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
15.381 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
1.000 |
| 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 |
06:52:55.50 |
-34:14:11.8 |
HIP 33170 |
16.41 |
| 2026-02-03 12:00 |
06:52:51.96 |
-34:13:45.7 |
HIP 33170 |
17.13 |
| 2026-02-04 00:00 |
06:52:48.44 |
-34:13:19.4 |
HIP 33170 |
17.85 |
| 2026-02-04 12:00 |
06:52:44.95 |
-34:12:52.8 |
HIP 33170 |
18.58 |
| 2026-02-05 00:00 |
06:52:41.47 |
-34:12:25.9 |
HIP 32970 |
19.30 |
| 2026-02-05 12:00 |
06:52:38.01 |
-34:11:58.7 |
HIP 32970 |
18.59 |
| 2026-02-06 00:00 |
06:52:34.57 |
-34:11:31.2 |
HIP 32970 |
17.89 |
| 2026-02-06 12:00 |
06:52:31.16 |
-34:11:03.5 |
HIP 32970 |
17.20 |
| 2026-02-07 00:00 |
06:52:27.76 |
-34:10:35.4 |
HIP 32970 |
16.53 |
| 2026-02-07 12:00 |
06:52:24.39 |
-34:10:07.1 |
HIP 32970 |
15.86 |
| 2026-02-08 00:00 |
06:52:21.04 |
-34:09:38.5 |
HIP 32970 |
15.21 |
| 2026-02-08 12:00 |
06:52:17.71 |
-34:09:09.6 |
HIP 32970 |
14.58 |
| 2026-02-09 00:00 |
06:52:14.40 |
-34:08:40.4 |
HIP 32970 |
13.97 |
| 2026-02-09 12:00 |
06:52:11.12 |
-34:08:11.0 |
HIP 32970 |
13.37 |
| 2026-02-10 00:00 |
06:52:07.85 |
-34:07:41.3 |
HIP 32970 |
12.80 |
| 2026-02-10 12:00 |
06:52:04.61 |
-34:07:11.3 |
HIP 32970 |
12.26 |
| 2026-02-11 00:00 |
06:52:01.40 |
-34:06:41.1 |
HIP 32970 |
11.74 |
| 2026-02-11 12:00 |
06:51:58.20 |
-34:06:10.6 |
HIP 32970 |
11.26 |
| 2026-02-12 00:00 |
06:51:55.04 |
-34:05:39.8 |
HIP 32970 |
10.82 |
| 2026-02-12 12:00 |
06:51:51.89 |
-34:05:08.8 |
HIP 32970 |
10.42 |
| 2026-02-13 00:00 |
06:51:48.77 |
-34:04:37.5 |
HIP 32970 |
10.07 |
| 2026-02-13 12:00 |
06:51:45.67 |
-34:04:05.9 |
HIP 32970 |
9.77 |
| 2026-02-14 00:00 |
06:51:42.60 |
-34:03:34.2 |
HIP 32970 |
9.52 |
| 2026-02-14 12:00 |
06:51:39.55 |
-34:03:02.1 |
HIP 32970 |
9.34 |
| 2026-02-15 00:00 |
06:51:36.53 |
-34:02:29.8 |
HIP 32970 |
9.22 |
| 2026-02-15 12:00 |
06:51:33.53 |
-34:01:57.3 |
HIP 32970 |
9.17 |
| 2026-02-16 00:00 |
06:51:30.56 |
-34:01:24.5 |
HIP 32970 |
9.19 |
| 2026-02-16 12:00 |
06:51:27.62 |
-34:00:51.5 |
HIP 32970 |
9.28 |
| 2026-02-17 00:00 |
06:51:24.70 |
-34:00:18.3 |
HIP 32970 |
9.42 |
| 2026-02-17 12:00 |
06:51:21.81 |
-33:59:44.8 |
HIP 32970 |
9.63 |
| 2026-02-18 00:00 |
06:51:18.94 |
-33:59:11.1 |
HIP 32970 |
9.90 |
| 2026-02-18 12:00 |
06:51:16.10 |
-33:58:37.2 |
HIP 32970 |
10.22 |
| 2026-02-19 00:00 |
06:51:13.29 |
-33:58:03.1 |
HIP 32970 |
10.58 |
| 2026-02-19 12:00 |
06:51:10.50 |
-33:57:28.7 |
HIP 32970 |
10.99 |
| 2026-02-20 00:00 |
06:51:07.74 |
-33:56:54.1 |
HIP 32970 |
11.44 |
| 2026-02-20 12:00 |
06:51:05.01 |
-33:56:19.3 |
HIP 32788 |
11.68 |
| 2026-02-21 00:00 |
06:51:02.31 |
-33:55:44.3 |
HIP 32788 |
10.99 |
| 2026-02-21 12:00 |
06:50:59.63 |
-33:55:09.1 |
HIP 32788 |
10.33 |
| 2026-02-22 00:00 |
06:50:56.99 |
-33:54:33.7 |
HIP 32788 |
9.68 |
| 2026-02-22 12:00 |
06:50:54.37 |
-33:53:58.1 |
HIP 32788 |
9.07 |
| 2026-02-23 00:00 |
06:50:51.78 |
-33:53:22.3 |
HIP 32788 |
8.50 |
| 2026-02-23 12:00 |
06:50:49.21 |
-33:52:46.3 |
HIP 32788 |
7.98 |
| 2026-02-24 00:00 |
06:50:46.68 |
-33:52:10.0 |
HIP 32788 |
7.51 |