300P/Catalina
| Parameter |
Value |
| Designation |
300P/Catalina |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2018-11-02T01:00:23.175360Z |
| Orbit solution date (soln_date, UTC) |
2023-11-14T12:36:26Z |
| Obs used |
148 |
| NEO |
Yes |
| M1 |
16.800 |
| K1 |
20.500 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2018-01-04.0000000 |
| e |
0.69162623 |
| q (au) |
0.832296 |
| a (au) |
2.698984 |
| i (deg) |
5.675932 |
| Ω (om, deg) |
95.686317 |
| ω (w, deg) |
222.865728 |
| M (ma, deg) |
292.861604 |
Magnitude
Scatter + Global Linear
$$
M_a = (17.367 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
17.367 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2023-02-17 |
2023-04-11 |
+15.3858 |
+0.614 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-02-03 00:00 |
10:40:56.54 |
+14:46:36.0 |
HIP 52242 |
13.52 |
| 2026-02-03 12:00 |
10:40:35.52 |
+14:49:11.5 |
HIP 52242 |
8.97 |
| 2026-02-04 00:00 |
10:40:14.32 |
+14:51:47.5 |
HIP 52242 |
6.57 |
| 2026-02-04 12:00 |
10:39:52.95 |
+14:54:23.9 |
HIP 52242 |
8.52 |
| 2026-02-05 00:00 |
10:39:31.40 |
+14:57:00.8 |
HIP 52242 |
13.03 |
| 2026-02-05 12:00 |
10:39:09.67 |
+14:59:38.1 |
HIP 52147 |
15.68 |
| 2026-02-06 00:00 |
10:38:47.78 |
+15:02:15.9 |
HIP 52033 |
13.18 |
| 2026-02-06 12:00 |
10:38:25.72 |
+15:04:53.9 |
HIP 52033 |
8.89 |
| 2026-02-07 00:00 |
10:38:03.50 |
+15:07:32.3 |
HIP 52033 |
7.41 |
| 2026-02-07 12:00 |
10:37:41.12 |
+15:10:11.1 |
HIP 52033 |
10.13 |
| 2026-02-08 00:00 |
10:37:18.58 |
+15:12:50.1 |
HIP 51959 |
6.55 |
| 2026-02-08 12:00 |
10:36:55.89 |
+15:15:29.3 |
HIP 51959 |
4.36 |
| 2026-02-09 00:00 |
10:36:33.04 |
+15:18:08.8 |
HIP 51959 |
8.34 |
| 2026-02-09 12:00 |
10:36:10.06 |
+15:20:48.5 |
HIP 51959 |
13.99 |
| 2026-02-10 00:00 |
10:35:46.93 |
+15:23:28.4 |
HIP 51959 |
19.96 |
| 2026-02-10 12:00 |
10:35:23.65 |
+15:26:08.4 |
HIP 51959 |
26.06 |
| 2026-02-11 00:00 |
10:35:00.25 |
+15:28:48.5 |
HIP 51690 |
26.36 |
| 2026-02-11 12:00 |
10:34:36.71 |
+15:31:28.7 |
HIP 51690 |
24.11 |
| 2026-02-12 00:00 |
10:34:13.04 |
+15:34:08.9 |
HIP 51690 |
23.37 |
| 2026-02-12 12:00 |
10:33:49.25 |
+15:36:49.2 |
HIP 51690 |
24.30 |
| 2026-02-13 00:00 |
10:33:25.34 |
+15:39:29.5 |
HIP 51690 |
26.73 |
| 2026-02-13 12:00 |
10:33:01.31 |
+15:42:09.7 |
HIP 51690 |
30.33 |
| 2026-02-14 00:00 |
10:32:37.17 |
+15:44:49.9 |
HIP 51479 |
26.52 |
| 2026-02-14 12:00 |
10:32:12.93 |
+15:47:29.9 |
HIP 51479 |
20.12 |
| 2026-02-15 00:00 |
10:31:48.57 |
+15:50:09.8 |
HIP 51479 |
13.71 |
| 2026-02-15 12:00 |
10:31:24.12 |
+15:52:49.6 |
HIP 51479 |
7.33 |
| 2026-02-16 00:00 |
10:30:59.57 |
+15:55:29.2 |
HIP 51479 |
1.68 |
| 2026-02-16 12:00 |
10:30:34.93 |
+15:58:08.5 |
HIP 51479 |
5.99 |
| 2026-02-17 00:00 |
10:30:10.20 |
+16:00:47.7 |
HIP 51479 |
12.39 |
| 2026-02-17 12:00 |
10:29:45.39 |
+16:03:26.5 |
HIP 51479 |
18.88 |
| 2026-02-18 00:00 |
10:29:20.51 |
+16:06:05.0 |
HIP 51279 |
24.47 |
| 2026-02-18 12:00 |
10:28:55.54 |
+16:08:43.2 |
HIP 51221 |
21.26 |
| 2026-02-19 00:00 |
10:28:30.51 |
+16:11:21.0 |
HIP 51221 |
14.91 |
| 2026-02-19 12:00 |
10:28:05.42 |
+16:13:58.3 |
HIP 51221 |
8.85 |
| 2026-02-20 00:00 |
10:27:40.26 |
+16:16:35.3 |
HIP 51221 |
4.57 |
| 2026-02-20 12:00 |
10:27:15.05 |
+16:19:11.8 |
HIP 51221 |
7.09 |
| 2026-02-21 00:00 |
10:26:49.78 |
+16:21:47.8 |
HIP 51221 |
12.91 |
| 2026-02-21 12:00 |
10:26:24.47 |
+16:24:23.3 |
HIP 51221 |
19.24 |
| 2026-02-22 00:00 |
10:25:59.12 |
+16:26:58.2 |
HIP 51221 |
25.72 |
| 2026-02-22 12:00 |
10:25:33.73 |
+16:29:32.5 |
HIP 51020 |
25.79 |
| 2026-02-23 00:00 |
10:25:08.31 |
+16:32:06.2 |
HIP 51020 |
23.39 |
| 2026-02-23 12:00 |
10:24:42.87 |
+16:34:39.3 |
HIP 51020 |
22.73 |
| 2026-02-24 00:00 |
10:24:17.39 |
+16:37:11.8 |
HIP 51020 |
23.96 |