| Parameter |
Value |
| Designation |
C/2020 K3 (Leonard) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2020-05-30T02:55:42.355200Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:34:07Z |
| Obs used |
212 |
| NEO |
- |
| M1 |
14.900 |
| K1 |
13.000 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2020-05-22T10:46:25.824000Z |
| Discovery magnitude (MPC) |
18.00 G |
| Discovery observatory (MPC) |
703 · University of Arizona Catalina Sky Survey |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2020-06-08.0000000 |
| e |
0.99242187 |
| q (au) |
1.593446 |
| a (au) |
210.269034 |
| i (deg) |
128.715444 |
| Ω (om, deg) |
27.927767 |
| ω (w, deg) |
62.697775 |
| M (ma, deg) |
0.002870 |
Magnitude
Scatter + Global Linear
$$
M_a = (15.248 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
15.248 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.656 |
| 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 |
| 2019-10-25 |
2020-05-29 |
+3.6819 |
-1.535 |
| 2020-05-31 |
2020-09-12 |
+12.6466 |
-2.959 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-06-01 00:00 |
11:47:04.91 |
-22:30:29.3 |
HIP 57583 |
28.06 |
| 2026-06-01 12:00 |
11:47:02.28 |
-22:29:41.8 |
HIP 57343 |
27.11 |
| 2026-06-02 00:00 |
11:46:59.72 |
-22:28:54.6 |
HIP 57343 |
26.17 |
| 2026-06-02 12:00 |
11:46:57.22 |
-22:28:07.7 |
HIP 57343 |
25.26 |
| 2026-06-03 00:00 |
11:46:54.77 |
-22:27:21.0 |
HIP 57343 |
24.36 |
| 2026-06-03 12:00 |
11:46:52.39 |
-22:26:34.6 |
HIP 57343 |
23.48 |
| 2026-06-04 00:00 |
11:46:50.07 |
-22:25:48.5 |
HIP 57343 |
22.62 |
| 2026-06-04 12:00 |
11:46:47.81 |
-22:25:02.7 |
HIP 57343 |
21.78 |
| 2026-06-05 00:00 |
11:46:45.61 |
-22:24:17.1 |
HIP 57343 |
20.96 |
| 2026-06-05 12:00 |
11:46:43.47 |
-22:23:31.9 |
HIP 57343 |
20.17 |
| 2026-06-06 00:00 |
11:46:41.39 |
-22:22:46.9 |
HIP 57343 |
19.40 |
| 2026-06-06 12:00 |
11:46:39.37 |
-22:22:02.3 |
HIP 57343 |
18.66 |
| 2026-06-07 00:00 |
11:46:37.41 |
-22:21:17.9 |
HIP 57343 |
17.94 |
| 2026-06-07 12:00 |
11:46:35.51 |
-22:20:33.9 |
HIP 57343 |
17.25 |
| 2026-06-08 00:00 |
11:46:33.67 |
-22:19:50.1 |
HIP 57343 |
16.59 |
| 2026-06-08 12:00 |
11:46:31.89 |
-22:19:06.7 |
HIP 57343 |
15.97 |
| 2026-06-09 00:00 |
11:46:30.18 |
-22:18:23.5 |
HIP 57343 |
15.37 |
| 2026-06-09 12:00 |
11:46:28.52 |
-22:17:40.7 |
HIP 57343 |
14.82 |
| 2026-06-10 00:00 |
11:46:26.92 |
-22:16:58.2 |
HIP 57343 |
14.30 |
| 2026-06-10 12:00 |
11:46:25.39 |
-22:16:16.1 |
HIP 57343 |
13.83 |
| 2026-06-11 00:00 |
11:46:23.91 |
-22:15:34.2 |
HIP 57343 |
13.40 |
| 2026-06-11 12:00 |
11:46:22.50 |
-22:14:52.7 |
HIP 57343 |
13.01 |
| 2026-06-12 00:00 |
11:46:21.14 |
-22:14:11.5 |
HIP 57343 |
12.68 |
| 2026-06-12 12:00 |
11:46:19.85 |
-22:13:30.7 |
HIP 57343 |
12.39 |
| 2026-06-13 00:00 |
11:46:18.61 |
-22:12:50.2 |
HIP 57343 |
12.16 |
| 2026-06-13 12:00 |
11:46:17.44 |
-22:12:10.0 |
HIP 57343 |
11.98 |
| 2026-06-14 00:00 |
11:46:16.32 |
-22:11:30.2 |
HIP 57343 |
11.85 |
| 2026-06-14 12:00 |
11:46:15.27 |
-22:10:50.7 |
HIP 57343 |
11.78 |
| 2026-06-15 00:00 |
11:46:14.27 |
-22:10:11.6 |
HIP 57343 |
11.76 |
| 2026-06-15 12:00 |
11:46:13.34 |
-22:09:32.8 |
HIP 57343 |
11.79 |
| 2026-06-16 00:00 |
11:46:12.46 |
-22:08:54.4 |
HIP 57343 |
11.87 |
| 2026-06-16 12:00 |
11:46:11.65 |
-22:08:16.3 |
HIP 57343 |
12.00 |
| 2026-06-17 00:00 |
11:46:10.89 |
-22:07:38.6 |
HIP 57343 |
12.17 |
| 2026-06-17 12:00 |
11:46:10.19 |
-22:07:01.3 |
HIP 57343 |
12.38 |
| 2026-06-18 00:00 |
11:46:09.56 |
-22:06:24.3 |
HIP 57343 |
12.62 |
| 2026-06-18 12:00 |
11:46:08.98 |
-22:05:47.7 |
HIP 57343 |
12.90 |
| 2026-06-19 00:00 |
11:46:08.46 |
-22:05:11.5 |
HIP 57343 |
13.21 |
| 2026-06-19 12:00 |
11:46:08.00 |
-22:04:35.6 |
HIP 57343 |
13.55 |
| 2026-06-20 00:00 |
11:46:07.59 |
-22:04:00.2 |
HIP 57343 |
13.90 |
| 2026-06-20 12:00 |
11:46:07.25 |
-22:03:25.1 |
HIP 57343 |
14.28 |
| 2026-06-21 00:00 |
11:46:06.96 |
-22:02:50.4 |
HIP 57343 |
14.68 |
| 2026-06-21 12:00 |
11:46:06.74 |
-22:02:16.0 |
HIP 57343 |
15.09 |
| 2026-06-22 00:00 |
11:46:06.57 |
-22:01:42.1 |
HIP 57343 |
15.51 |