| Parameter |
Value |
| Designation |
396P/Leonard |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2019-08-29T03:15:14.060160Z |
| Orbit solution date (soln_date, UTC) |
2023-04-24T23:29:36Z |
| Obs used |
115 |
| NEO |
- |
| M1 |
15.700 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2018-05-09.0000000 |
| e |
0.41780395 |
| q (au) |
3.983116 |
| a (au) |
6.841537 |
| i (deg) |
5.434040 |
| Ω (om, deg) |
136.663398 |
| ω (w, deg) |
8.678978 |
| M (ma, deg) |
333.720604 |
Magnitude
Scatter + Global Linear
$$
M_a = (9.411 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
9.411 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.855 |
| k |
0.998 |
| 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) |
| 2026-05-12 00:00 |
20:51:13.73 |
-16:25:29.0 |
HIP 102922 |
2.00 |
| 2026-05-12 12:00 |
20:51:14.81 |
-16:25:25.5 |
HIP 102922 |
2.24 |
| 2026-05-13 00:00 |
20:51:15.79 |
-16:25:22.5 |
HIP 102922 |
2.46 |
| 2026-05-13 12:00 |
20:51:16.66 |
-16:25:19.9 |
HIP 102922 |
2.65 |
| 2026-05-14 00:00 |
20:51:17.42 |
-16:25:17.8 |
HIP 102922 |
2.83 |
| 2026-05-14 12:00 |
20:51:18.07 |
-16:25:16.1 |
HIP 102922 |
2.98 |
| 2026-05-15 00:00 |
20:51:18.62 |
-16:25:14.9 |
HIP 102922 |
3.10 |
| 2026-05-15 12:00 |
20:51:19.05 |
-16:25:14.1 |
HIP 102922 |
3.21 |
| 2026-05-16 00:00 |
20:51:19.38 |
-16:25:13.7 |
HIP 102922 |
3.28 |
| 2026-05-16 12:00 |
20:51:19.60 |
-16:25:13.8 |
HIP 102922 |
3.34 |
| 2026-05-17 00:00 |
20:51:19.71 |
-16:25:14.4 |
HIP 102922 |
3.36 |
| 2026-05-17 12:00 |
20:51:19.71 |
-16:25:15.4 |
HIP 102922 |
3.37 |
| 2026-05-18 00:00 |
20:51:19.60 |
-16:25:16.8 |
HIP 102922 |
3.34 |
| 2026-05-18 12:00 |
20:51:19.39 |
-16:25:18.7 |
HIP 102922 |
3.30 |
| 2026-05-19 00:00 |
20:51:19.06 |
-16:25:21.1 |
HIP 102922 |
3.22 |
| 2026-05-19 12:00 |
20:51:18.63 |
-16:25:23.9 |
HIP 102922 |
3.13 |
| 2026-05-20 00:00 |
20:51:18.09 |
-16:25:27.2 |
HIP 102922 |
3.01 |
| 2026-05-20 12:00 |
20:51:17.44 |
-16:25:30.9 |
HIP 102922 |
2.87 |
| 2026-05-21 00:00 |
20:51:16.69 |
-16:25:35.0 |
HIP 102922 |
2.71 |
| 2026-05-21 12:00 |
20:51:15.82 |
-16:25:39.6 |
HIP 102922 |
2.54 |
| 2026-05-22 00:00 |
20:51:14.85 |
-16:25:44.7 |
HIP 102922 |
2.35 |
| 2026-05-22 12:00 |
20:51:13.78 |
-16:25:50.2 |
HIP 102922 |
2.15 |
| 2026-05-23 00:00 |
20:51:12.59 |
-16:25:56.2 |
HIP 102922 |
1.95 |
| 2026-05-23 12:00 |
20:51:11.30 |
-16:26:02.6 |
HIP 102922 |
1.77 |
| 2026-05-24 00:00 |
20:51:09.90 |
-16:26:09.4 |
HIP 102922 |
1.62 |
| 2026-05-24 12:00 |
20:51:08.39 |
-16:26:16.7 |
HIP 102922 |
1.54 |
| 2026-05-25 00:00 |
20:51:06.78 |
-16:26:24.4 |
HIP 102922 |
1.55 |
| 2026-05-25 12:00 |
20:51:05.06 |
-16:26:32.6 |
HIP 102922 |
1.68 |
| 2026-05-26 00:00 |
20:51:03.23 |
-16:26:41.2 |
HIP 102922 |
1.91 |
| 2026-05-26 12:00 |
20:51:01.30 |
-16:26:50.3 |
HIP 102922 |
2.24 |
| 2026-05-27 00:00 |
20:50:59.26 |
-16:26:59.8 |
HIP 102922 |
2.63 |
| 2026-05-27 12:00 |
20:50:57.12 |
-16:27:09.7 |
HIP 102922 |
3.09 |
| 2026-05-28 00:00 |
20:50:54.87 |
-16:27:20.1 |
HIP 102922 |
3.59 |
| 2026-05-28 12:00 |
20:50:52.52 |
-16:27:31.0 |
HIP 102922 |
4.13 |
| 2026-05-29 00:00 |
20:50:50.06 |
-16:27:42.2 |
HIP 102922 |
4.71 |
| 2026-05-29 12:00 |
20:50:47.50 |
-16:27:53.9 |
HIP 102922 |
5.32 |
| 2026-05-30 00:00 |
20:50:44.83 |
-16:28:06.1 |
HIP 102922 |
5.97 |
| 2026-05-30 12:00 |
20:50:42.06 |
-16:28:18.6 |
HIP 102922 |
6.64 |
| 2026-05-31 00:00 |
20:50:39.18 |
-16:28:31.6 |
HIP 102922 |
7.35 |
| 2026-05-31 12:00 |
20:50:36.20 |
-16:28:45.1 |
HIP 102922 |
8.08 |
| 2026-06-01 00:00 |
20:50:33.12 |
-16:28:59.0 |
HIP 102922 |
8.84 |
| 2026-06-01 12:00 |
20:50:29.93 |
-16:29:13.3 |
HIP 102922 |
9.63 |
| 2026-06-02 00:00 |
20:50:26.64 |
-16:29:28.0 |
HIP 102922 |
10.44 |