| Parameter |
Value |
| Designation |
395P/Catalina-NEAT |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2021-12-30T11:54:17.147520Z |
| Orbit solution date (soln_date, UTC) |
2025-04-09T14:01:13Z |
| Obs used |
810 |
| NEO |
- |
| M1 |
9.900 |
| K1 |
10.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2022-03-31.0000000 |
| e |
0.38213832 |
| q (au) |
4.064893 |
| a (au) |
6.578970 |
| i (deg) |
3.276962 |
| Ω (om, deg) |
223.549119 |
| ω (w, deg) |
89.966129 |
| M (ma, deg) |
5.286093 |
Magnitude
Scatter + Global Linear
$$
M_a = (8.462 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
8.462 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.762 |
| 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 |
| 2020-04-26 |
2021-11-28 |
+16.3019 |
-9.562 |
| 2022-06-06 |
2023-10-18 |
+22.4213 |
-14.528 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-09-20 00:00 |
06:34:37.54 |
+20:30:02.9 |
HIP 31327 |
12.51 |
| 2026-09-20 12:00 |
06:34:44.55 |
+20:29:44.8 |
HIP 31327 |
13.70 |
| 2026-09-21 00:00 |
06:34:51.43 |
+20:29:26.8 |
HIP 31327 |
14.96 |
| 2026-09-21 12:00 |
06:34:58.20 |
+20:29:08.8 |
HIP 31327 |
16.27 |
| 2026-09-22 00:00 |
06:35:04.86 |
+20:28:50.8 |
HIP 31327 |
17.61 |
| 2026-09-22 12:00 |
06:35:11.39 |
+20:28:32.9 |
HIP 31327 |
18.96 |
| 2026-09-23 00:00 |
06:35:17.81 |
+20:28:15.0 |
HIP 31327 |
20.32 |
| 2026-09-23 12:00 |
06:35:24.11 |
+20:27:57.2 |
HIP 31327 |
21.69 |
| 2026-09-24 00:00 |
06:35:30.29 |
+20:27:39.5 |
HIP 31327 |
23.04 |
| 2026-09-24 12:00 |
06:35:36.35 |
+20:27:21.8 |
HIP 31327 |
24.39 |
| 2026-09-25 00:00 |
06:35:42.29 |
+20:27:04.2 |
HIP 31327 |
25.72 |
| 2026-09-25 12:00 |
06:35:48.11 |
+20:26:46.6 |
HIP 31483 |
26.69 |
| 2026-09-26 00:00 |
06:35:53.81 |
+20:26:29.1 |
HIP 31483 |
27.15 |
| 2026-09-26 12:00 |
06:35:59.39 |
+20:26:11.6 |
HIP 31483 |
27.66 |
| 2026-09-27 00:00 |
06:36:04.84 |
+20:25:54.2 |
HIP 31483 |
28.21 |
| 2026-09-27 12:00 |
06:36:10.18 |
+20:25:36.9 |
HIP 31483 |
28.81 |
| 2026-09-28 00:00 |
06:36:15.39 |
+20:25:19.7 |
HIP 31680 |
28.27 |
| 2026-09-28 12:00 |
06:36:20.48 |
+20:25:02.5 |
HIP 31680 |
27.22 |
| 2026-09-29 00:00 |
06:36:25.45 |
+20:24:45.4 |
HIP 31680 |
26.20 |
| 2026-09-29 12:00 |
06:36:30.29 |
+20:24:28.3 |
HIP 31680 |
25.22 |
| 2026-09-30 00:00 |
06:36:35.01 |
+20:24:11.4 |
HIP 31680 |
24.27 |
| 2026-09-30 12:00 |
06:36:39.61 |
+20:23:54.5 |
HIP 31680 |
23.36 |
| 2026-10-01 00:00 |
06:36:44.08 |
+20:23:37.7 |
HIP 31680 |
22.49 |
| 2026-10-01 12:00 |
06:36:48.42 |
+20:23:20.9 |
HIP 31680 |
21.66 |
| 2026-10-02 00:00 |
06:36:52.64 |
+20:23:04.3 |
HIP 31680 |
20.86 |
| 2026-10-02 12:00 |
06:36:56.73 |
+20:22:47.7 |
HIP 31680 |
20.11 |
| 2026-10-03 00:00 |
06:37:00.70 |
+20:22:31.2 |
HIP 31680 |
19.39 |
| 2026-10-03 12:00 |
06:37:04.54 |
+20:22:14.8 |
HIP 31680 |
18.71 |
| 2026-10-04 00:00 |
06:37:08.25 |
+20:21:58.5 |
HIP 31680 |
18.06 |
| 2026-10-04 12:00 |
06:37:11.83 |
+20:21:42.3 |
HIP 31680 |
17.46 |
| 2026-10-05 00:00 |
06:37:15.29 |
+20:21:26.2 |
HIP 31680 |
16.89 |
| 2026-10-05 12:00 |
06:37:18.61 |
+20:21:10.1 |
HIP 31680 |
16.36 |
| 2026-10-06 00:00 |
06:37:21.81 |
+20:20:54.2 |
HIP 31680 |
15.86 |
| 2026-10-06 12:00 |
06:37:24.87 |
+20:20:38.3 |
HIP 31680 |
15.40 |
| 2026-10-07 00:00 |
06:37:27.81 |
+20:20:22.6 |
HIP 31680 |
14.98 |
| 2026-10-07 12:00 |
06:37:30.62 |
+20:20:06.9 |
HIP 31680 |
14.58 |
| 2026-10-08 00:00 |
06:37:33.29 |
+20:19:51.4 |
HIP 31680 |
14.22 |
| 2026-10-08 12:00 |
06:37:35.84 |
+20:19:36.0 |
HIP 31680 |
13.88 |
| 2026-10-09 00:00 |
06:37:38.25 |
+20:19:20.6 |
HIP 31680 |
13.57 |
| 2026-10-09 12:00 |
06:37:40.53 |
+20:19:05.4 |
HIP 31680 |
13.29 |
| 2026-10-10 00:00 |
06:37:42.68 |
+20:18:50.3 |
HIP 31680 |
13.03 |
| 2026-10-10 12:00 |
06:37:44.70 |
+20:18:35.2 |
HIP 31680 |
12.79 |
| 2026-10-11 00:00 |
06:37:46.59 |
+20:18:20.3 |
HIP 31680 |
12.57 |