| Parameter |
Value |
| Designation |
C/2005 J2 (Catalina) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2005-04-04T06:52:12.155520Z |
| Orbit solution date (soln_date, UTC) |
2021-04-16T12:11:39Z |
| Obs used |
65 |
| NEO |
- |
| M1 |
9.000 |
| K1 |
10.000 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2005-05-25.0000000 |
| e |
1.00000000 |
| q (au) |
4.287489 |
| a (au) |
-433338614767.913574 |
| i (deg) |
150.803021 |
| Ω (om, deg) |
33.369506 |
| ω (w, deg) |
199.642613 |
| M (ma, deg) |
0.000000 |
Magnitude
Scatter + Global Linear
$$
M_a = (11.585 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
11.585 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-1.000 |
| 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) |
| 2026-03-26 00:00 |
03:16:39.47 |
+08:51:56.4 |
HIP 15298 |
17.89 |
| 2026-03-26 12:00 |
03:16:41.25 |
+08:52:10.3 |
HIP 15298 |
17.45 |
| 2026-03-27 00:00 |
03:16:43.04 |
+08:52:24.2 |
HIP 15298 |
17.00 |
| 2026-03-27 12:00 |
03:16:44.86 |
+08:52:38.2 |
HIP 15298 |
16.56 |
| 2026-03-28 00:00 |
03:16:46.69 |
+08:52:52.2 |
HIP 15298 |
16.11 |
| 2026-03-28 12:00 |
03:16:48.53 |
+08:53:06.2 |
HIP 15298 |
15.67 |
| 2026-03-29 00:00 |
03:16:50.39 |
+08:53:20.2 |
HIP 15298 |
15.23 |
| 2026-03-29 12:00 |
03:16:52.27 |
+08:53:34.2 |
HIP 15298 |
14.79 |
| 2026-03-30 00:00 |
03:16:54.17 |
+08:53:48.3 |
HIP 15298 |
14.36 |
| 2026-03-30 12:00 |
03:16:56.08 |
+08:54:02.4 |
HIP 15298 |
13.93 |
| 2026-03-31 00:00 |
03:16:58.01 |
+08:54:16.5 |
HIP 15298 |
13.50 |
| 2026-03-31 12:00 |
03:16:59.95 |
+08:54:30.6 |
HIP 15298 |
13.08 |
| 2026-04-01 00:00 |
03:17:01.91 |
+08:54:44.7 |
HIP 15298 |
12.67 |
| 2026-04-01 12:00 |
03:17:03.89 |
+08:54:58.8 |
HIP 15298 |
12.26 |
| 2026-04-02 00:00 |
03:17:05.88 |
+08:55:12.9 |
HIP 15298 |
11.87 |
| 2026-04-02 12:00 |
03:17:07.88 |
+08:55:27.1 |
HIP 15298 |
11.48 |
| 2026-04-03 00:00 |
03:17:09.91 |
+08:55:41.2 |
HIP 15298 |
11.11 |
| 2026-04-03 12:00 |
03:17:11.94 |
+08:55:55.4 |
HIP 15298 |
10.75 |
| 2026-04-04 00:00 |
03:17:13.99 |
+08:56:09.5 |
HIP 15298 |
10.41 |
| 2026-04-04 12:00 |
03:17:16.06 |
+08:56:23.7 |
HIP 15298 |
10.09 |
| 2026-04-05 00:00 |
03:17:18.14 |
+08:56:37.9 |
HIP 15298 |
9.78 |
| 2026-04-05 12:00 |
03:17:20.23 |
+08:56:52.1 |
HIP 15298 |
9.51 |
| 2026-04-06 00:00 |
03:17:22.34 |
+08:57:06.2 |
HIP 15298 |
9.25 |
| 2026-04-06 12:00 |
03:17:24.47 |
+08:57:20.4 |
HIP 15298 |
9.03 |
| 2026-04-07 00:00 |
03:17:26.60 |
+08:57:34.6 |
HIP 15298 |
8.84 |
| 2026-04-07 12:00 |
03:17:28.75 |
+08:57:48.8 |
HIP 15298 |
8.69 |
| 2026-04-08 00:00 |
03:17:30.92 |
+08:58:03.0 |
HIP 15298 |
8.57 |
| 2026-04-08 12:00 |
03:17:33.09 |
+08:58:17.2 |
HIP 15298 |
8.49 |
| 2026-04-09 00:00 |
03:17:35.29 |
+08:58:31.4 |
HIP 15298 |
8.46 |
| 2026-04-09 12:00 |
03:17:37.49 |
+08:58:45.6 |
HIP 15298 |
8.46 |
| 2026-04-10 00:00 |
03:17:39.71 |
+08:58:59.7 |
HIP 15298 |
8.51 |
| 2026-04-10 12:00 |
03:17:41.93 |
+08:59:13.9 |
HIP 15298 |
8.61 |
| 2026-04-11 00:00 |
03:17:44.18 |
+08:59:28.1 |
HIP 15298 |
8.74 |
| 2026-04-11 12:00 |
03:17:46.43 |
+08:59:42.3 |
HIP 15298 |
8.92 |
| 2026-04-12 00:00 |
03:17:48.70 |
+08:59:56.4 |
HIP 15298 |
9.13 |
| 2026-04-12 12:00 |
03:17:50.97 |
+09:00:10.6 |
HIP 15298 |
9.38 |
| 2026-04-13 00:00 |
03:17:53.26 |
+09:00:24.7 |
HIP 15298 |
9.67 |
| 2026-04-13 12:00 |
03:17:55.57 |
+09:00:38.8 |
HIP 15298 |
9.99 |
| 2026-04-14 00:00 |
03:17:57.88 |
+09:00:52.9 |
HIP 15298 |
10.33 |
| 2026-04-14 12:00 |
03:18:00.20 |
+09:01:07.1 |
HIP 15298 |
10.71 |
| 2026-04-15 00:00 |
03:18:02.54 |
+09:01:21.1 |
HIP 15298 |
11.11 |
| 2026-04-15 12:00 |
03:18:04.89 |
+09:01:35.2 |
HIP 15298 |
11.53 |
| 2026-04-16 00:00 |
03:18:07.24 |
+09:01:49.3 |
HIP 15298 |
11.97 |