| 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) |
| 2026-03-26 00:00 |
18:34:25.51 |
-62:35:41.9 |
HIP 91024 |
9.18 |
| 2026-03-26 12:00 |
18:34:26.84 |
-62:36:20.0 |
HIP 91024 |
8.60 |
| 2026-03-27 00:00 |
18:34:28.10 |
-62:36:58.1 |
HIP 91024 |
8.03 |
| 2026-03-27 12:00 |
18:34:29.28 |
-62:37:36.4 |
HIP 91024 |
7.47 |
| 2026-03-28 00:00 |
18:34:30.38 |
-62:38:14.6 |
HIP 91024 |
6.92 |
| 2026-03-28 12:00 |
18:34:31.39 |
-62:38:52.9 |
HIP 91024 |
6.38 |
| 2026-03-29 00:00 |
18:34:32.33 |
-62:39:31.3 |
HIP 91024 |
5.87 |
| 2026-03-29 12:00 |
18:34:33.19 |
-62:40:09.7 |
HIP 91024 |
5.38 |
| 2026-03-30 00:00 |
18:34:33.97 |
-62:40:48.1 |
HIP 91024 |
4.91 |
| 2026-03-30 12:00 |
18:34:34.67 |
-62:41:26.5 |
HIP 91024 |
4.49 |
| 2026-03-31 00:00 |
18:34:35.29 |
-62:42:05.0 |
HIP 91024 |
4.11 |
| 2026-03-31 12:00 |
18:34:35.83 |
-62:42:43.5 |
HIP 91024 |
3.80 |
| 2026-04-01 00:00 |
18:34:36.28 |
-62:43:22.0 |
HIP 91024 |
3.58 |
| 2026-04-01 12:00 |
18:34:36.66 |
-62:44:00.6 |
HIP 91024 |
3.45 |
| 2026-04-02 00:00 |
18:34:36.96 |
-62:44:39.1 |
HIP 91024 |
3.42 |
| 2026-04-02 12:00 |
18:34:37.18 |
-62:45:17.7 |
HIP 91024 |
3.51 |
| 2026-04-03 00:00 |
18:34:37.32 |
-62:45:56.3 |
HIP 91024 |
3.70 |
| 2026-04-03 12:00 |
18:34:37.37 |
-62:46:34.9 |
HIP 91024 |
3.98 |
| 2026-04-04 00:00 |
18:34:37.35 |
-62:47:13.5 |
HIP 91024 |
4.33 |
| 2026-04-04 12:00 |
18:34:37.24 |
-62:47:52.1 |
HIP 91024 |
4.74 |
| 2026-04-05 00:00 |
18:34:37.06 |
-62:48:30.6 |
HIP 91024 |
5.18 |
| 2026-04-05 12:00 |
18:34:36.79 |
-62:49:09.2 |
HIP 91024 |
5.66 |
| 2026-04-06 00:00 |
18:34:36.45 |
-62:49:47.8 |
HIP 91024 |
6.17 |
| 2026-04-06 12:00 |
18:34:36.02 |
-62:50:26.4 |
HIP 91024 |
6.69 |
| 2026-04-07 00:00 |
18:34:35.51 |
-62:51:05.0 |
HIP 91024 |
7.23 |
| 2026-04-07 12:00 |
18:34:34.92 |
-62:51:43.5 |
HIP 91024 |
7.78 |
| 2026-04-08 00:00 |
18:34:34.25 |
-62:52:22.0 |
HIP 91024 |
8.34 |
| 2026-04-08 12:00 |
18:34:33.50 |
-62:53:00.5 |
HIP 91024 |
8.91 |
| 2026-04-09 00:00 |
18:34:32.67 |
-62:53:39.0 |
HIP 91024 |
9.49 |
| 2026-04-09 12:00 |
18:34:31.76 |
-62:54:17.4 |
HIP 91024 |
10.07 |
| 2026-04-10 00:00 |
18:34:30.76 |
-62:54:55.9 |
HIP 91024 |
10.66 |
| 2026-04-10 12:00 |
18:34:29.69 |
-62:55:34.2 |
HIP 91024 |
11.25 |
| 2026-04-11 00:00 |
18:34:28.53 |
-62:56:12.6 |
HIP 91024 |
11.84 |
| 2026-04-11 12:00 |
18:34:27.29 |
-62:56:50.9 |
HIP 91024 |
12.44 |
| 2026-04-12 00:00 |
18:34:25.98 |
-62:57:29.1 |
HIP 91024 |
13.04 |
| 2026-04-12 12:00 |
18:34:24.58 |
-62:58:07.4 |
HIP 91024 |
13.64 |
| 2026-04-13 00:00 |
18:34:23.10 |
-62:58:45.5 |
HIP 91024 |
14.25 |
| 2026-04-13 12:00 |
18:34:21.54 |
-62:59:23.6 |
HIP 91024 |
14.86 |
| 2026-04-14 00:00 |
18:34:19.90 |
-63:00:01.7 |
HIP 91024 |
15.47 |
| 2026-04-14 12:00 |
18:34:18.18 |
-63:00:39.6 |
HIP 91024 |
16.09 |
| 2026-04-15 00:00 |
18:34:16.37 |
-63:01:17.6 |
HIP 91024 |
16.70 |
| 2026-04-15 12:00 |
18:34:14.49 |
-63:01:55.4 |
HIP 91024 |
17.32 |
| 2026-04-16 00:00 |
18:34:12.53 |
-63:02:33.2 |
HIP 91024 |
17.94 |