| Parameter |
Value |
| Designation |
C/2013 B2 (Catalina) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2013-07-01T12:27:38.249280Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:30Z |
| Obs used |
136 |
| NEO |
- |
| M1 |
13.100 |
| K1 |
5.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2013-05-16.0000000 |
| e |
1.00270297 |
| q (au) |
3.734135 |
| a (au) |
-1381.494777 |
| i (deg) |
43.454890 |
| Ω (om, deg) |
331.958789 |
| ω (w, deg) |
156.433585 |
| M (ma, deg) |
-0.000893 |
Magnitude
Scatter + Global Linear
$$
M_a = (6.637 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
6.637 |
| n |
6.000 |
| 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) |
| 2026-06-01 00:00 |
18:26:06.90 |
-63:48:10.0 |
HIP 90155 |
29.12 |
| 2026-06-01 12:00 |
18:25:58.96 |
-63:48:27.5 |
HIP 90155 |
28.94 |
| 2026-06-02 00:00 |
18:25:50.99 |
-63:48:44.6 |
HIP 90155 |
28.77 |
| 2026-06-02 12:00 |
18:25:42.97 |
-63:49:01.4 |
HIP 90155 |
28.63 |
| 2026-06-03 00:00 |
18:25:34.92 |
-63:49:17.8 |
HIP 90155 |
28.51 |
| 2026-06-03 12:00 |
18:25:26.83 |
-63:49:33.9 |
HIP 90155 |
28.41 |
| 2026-06-04 00:00 |
18:25:18.71 |
-63:49:49.7 |
HIP 90155 |
28.34 |
| 2026-06-04 12:00 |
18:25:10.55 |
-63:50:05.1 |
HIP 90155 |
28.29 |
| 2026-06-05 00:00 |
18:25:02.35 |
-63:50:20.1 |
HIP 90155 |
28.27 |
| 2026-06-05 12:00 |
18:24:54.13 |
-63:50:34.8 |
HIP 90155 |
28.27 |
| 2026-06-06 00:00 |
18:24:45.87 |
-63:50:49.1 |
HIP 90155 |
28.30 |
| 2026-06-06 12:00 |
18:24:37.58 |
-63:51:03.1 |
HIP 90155 |
28.35 |
| 2026-06-07 00:00 |
18:24:29.25 |
-63:51:16.7 |
HIP 90155 |
28.43 |
| 2026-06-07 12:00 |
18:24:20.90 |
-63:51:30.0 |
HIP 90155 |
28.53 |
| 2026-06-08 00:00 |
18:24:12.52 |
-63:51:42.9 |
HIP 90155 |
28.66 |
| 2026-06-08 12:00 |
18:24:04.11 |
-63:51:55.4 |
HIP 90155 |
28.82 |
| 2026-06-09 00:00 |
18:23:55.67 |
-63:52:07.6 |
HIP 89805 |
28.15 |
| 2026-06-09 12:00 |
18:23:47.20 |
-63:52:19.4 |
HIP 89805 |
27.21 |
| 2026-06-10 00:00 |
18:23:38.71 |
-63:52:30.9 |
HIP 89805 |
26.27 |
| 2026-06-10 12:00 |
18:23:30.19 |
-63:52:41.9 |
HIP 89805 |
25.33 |
| 2026-06-11 00:00 |
18:23:21.64 |
-63:52:52.6 |
HIP 89805 |
24.38 |
| 2026-06-11 12:00 |
18:23:13.07 |
-63:53:03.0 |
HIP 89805 |
23.44 |
| 2026-06-12 00:00 |
18:23:04.48 |
-63:53:12.9 |
HIP 89805 |
22.49 |
| 2026-06-12 12:00 |
18:22:55.86 |
-63:53:22.5 |
HIP 89805 |
21.54 |
| 2026-06-13 00:00 |
18:22:47.23 |
-63:53:31.7 |
HIP 89805 |
20.59 |
| 2026-06-13 12:00 |
18:22:38.57 |
-63:53:40.6 |
HIP 89805 |
19.64 |
| 2026-06-14 00:00 |
18:22:29.89 |
-63:53:49.0 |
HIP 89805 |
18.69 |
| 2026-06-14 12:00 |
18:22:21.19 |
-63:53:57.1 |
HIP 89805 |
17.74 |
| 2026-06-15 00:00 |
18:22:12.48 |
-63:54:04.8 |
HIP 89805 |
16.79 |
| 2026-06-15 12:00 |
18:22:03.75 |
-63:54:12.1 |
HIP 89805 |
15.84 |
| 2026-06-16 00:00 |
18:21:55.00 |
-63:54:19.0 |
HIP 89805 |
14.89 |
| 2026-06-16 12:00 |
18:21:46.23 |
-63:54:25.6 |
HIP 89805 |
13.93 |
| 2026-06-17 00:00 |
18:21:37.45 |
-63:54:31.8 |
HIP 89805 |
12.98 |
| 2026-06-17 12:00 |
18:21:28.66 |
-63:54:37.5 |
HIP 89805 |
12.03 |
| 2026-06-18 00:00 |
18:21:19.85 |
-63:54:42.9 |
HIP 89805 |
11.08 |
| 2026-06-18 12:00 |
18:21:11.04 |
-63:54:47.9 |
HIP 89805 |
10.14 |
| 2026-06-19 00:00 |
18:21:02.21 |
-63:54:52.6 |
HIP 89805 |
9.20 |
| 2026-06-19 12:00 |
18:20:53.37 |
-63:54:56.8 |
HIP 89805 |
8.26 |
| 2026-06-20 00:00 |
18:20:44.52 |
-63:55:00.6 |
HIP 89805 |
7.33 |
| 2026-06-20 12:00 |
18:20:35.66 |
-63:55:04.1 |
HIP 89805 |
6.41 |
| 2026-06-21 00:00 |
18:20:26.80 |
-63:55:07.2 |
HIP 89805 |
5.50 |
| 2026-06-21 12:00 |
18:20:17.93 |
-63:55:09.9 |
HIP 89805 |
4.62 |
| 2026-06-22 00:00 |
18:20:09.05 |
-63:55:12.2 |
HIP 89805 |
3.79 |