| Parameter |
Value |
| Designation |
C/2022 W3 (Leonard) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2023-06-22T18:37:13.267200Z |
| Orbit solution date (soln_date, UTC) |
2024-02-01T00:43:16Z |
| Obs used |
876 |
| NEO |
- |
| M1 |
15.600 |
| K1 |
4.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2022-11-26T11:27:43.689600Z |
| Discovery magnitude (MPC) |
19.72 G |
| Discovery observatory (MPC) |
G96 · Mt. Lemmon Survey |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2023-05-23.0000000 |
| e |
0.99503341 |
| q (au) |
1.397698 |
| a (au) |
281.420082 |
| i (deg) |
103.558036 |
| Ω (om, deg) |
132.268653 |
| ω (w, deg) |
116.521323 |
| M (ma, deg) |
359.993575 |
Magnitude
Scatter + Global Linear
$$
M_a = (15.045 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
15.045 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.992 |
| 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 |
| 2022-11-13 |
2022-12-26 |
+10.0116 |
-4.536 |
| 2022-12-26 |
2023-02-14 |
+14.3184 |
-6.086 |
| 2023-02-14 |
2023-06-22 |
+4.7617 |
-2.428 |
| 2023-06-24 |
2023-09-10 |
+9.8993 |
-1.871 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
00:56:14.60 |
-81:51:51.4 |
HIP 5228 |
26.21 |
| 2026-03-26 12:00 |
00:57:44.64 |
-81:51:36.6 |
HIP 5228 |
23.33 |
| 2026-03-27 00:00 |
00:59:14.70 |
-81:51:22.0 |
HIP 5228 |
20.55 |
| 2026-03-27 12:00 |
01:00:44.78 |
-81:51:07.8 |
HIP 5228 |
17.92 |
| 2026-03-28 00:00 |
01:02:14.89 |
-81:50:53.8 |
HIP 5228 |
15.53 |
| 2026-03-28 12:00 |
01:03:45.02 |
-81:50:40.1 |
HIP 5228 |
13.50 |
| 2026-03-29 00:00 |
01:05:15.18 |
-81:50:26.6 |
HIP 5228 |
12.02 |
| 2026-03-29 12:00 |
01:06:45.36 |
-81:50:13.5 |
HIP 5228 |
11.30 |
| 2026-03-30 00:00 |
01:08:15.56 |
-81:50:00.6 |
HIP 5228 |
11.49 |
| 2026-03-30 12:00 |
01:09:45.79 |
-81:49:48.0 |
HIP 5228 |
12.56 |
| 2026-03-31 00:00 |
01:11:16.05 |
-81:49:35.7 |
HIP 5228 |
14.30 |
| 2026-03-31 12:00 |
01:12:46.34 |
-81:49:23.6 |
HIP 5228 |
16.51 |
| 2026-04-01 00:00 |
01:14:16.66 |
-81:49:11.8 |
HIP 5964 |
17.56 |
| 2026-04-01 12:00 |
01:15:47.00 |
-81:49:00.3 |
HIP 5964 |
16.67 |
| 2026-04-02 00:00 |
01:17:17.38 |
-81:48:49.0 |
HIP 5964 |
16.41 |
| 2026-04-02 12:00 |
01:18:47.79 |
-81:48:38.0 |
HIP 5964 |
16.80 |
| 2026-04-03 00:00 |
01:20:18.23 |
-81:48:27.3 |
HIP 5964 |
17.80 |
| 2026-04-03 12:00 |
01:21:48.71 |
-81:48:16.8 |
HIP 5964 |
19.32 |
| 2026-04-04 00:00 |
01:23:19.22 |
-81:48:06.6 |
HIP 6916 |
18.69 |
| 2026-04-04 12:00 |
01:24:49.76 |
-81:47:56.7 |
HIP 6916 |
16.94 |
| 2026-04-05 00:00 |
01:26:20.34 |
-81:47:47.0 |
HIP 6916 |
15.66 |
| 2026-04-05 12:00 |
01:27:50.96 |
-81:47:37.5 |
HIP 6916 |
14.94 |
| 2026-04-06 00:00 |
01:29:21.61 |
-81:47:28.4 |
HIP 6916 |
14.89 |
| 2026-04-06 12:00 |
01:30:52.30 |
-81:47:19.5 |
HIP 6916 |
15.50 |
| 2026-04-07 00:00 |
01:32:23.03 |
-81:47:10.8 |
HIP 6916 |
16.71 |
| 2026-04-07 12:00 |
01:33:53.79 |
-81:47:02.4 |
HIP 6916 |
18.40 |
| 2026-04-08 00:00 |
01:35:24.60 |
-81:46:54.2 |
HIP 6916 |
20.45 |
| 2026-04-08 12:00 |
01:36:55.45 |
-81:46:46.3 |
HIP 6916 |
22.76 |
| 2026-04-09 00:00 |
01:38:26.33 |
-81:46:38.7 |
HIP 6916 |
25.27 |
| 2026-04-09 12:00 |
01:39:57.26 |
-81:46:31.3 |
HIP 6916 |
27.92 |
| 2026-04-10 00:00 |
01:41:28.23 |
-81:46:24.1 |
HIP 8499 |
30.62 |
| 2026-04-10 12:00 |
01:42:59.24 |
-81:46:17.2 |
HIP 8499 |
28.70 |
| 2026-04-11 00:00 |
01:44:30.30 |
-81:46:10.6 |
HIP 8499 |
27.06 |
| 2026-04-11 12:00 |
01:46:01.39 |
-81:46:04.2 |
HIP 8499 |
25.76 |
| 2026-04-12 00:00 |
01:47:32.53 |
-81:45:58.0 |
HIP 8499 |
24.84 |
| 2026-04-12 12:00 |
01:49:03.71 |
-81:45:52.1 |
HIP 9052 |
22.93 |
| 2026-04-13 00:00 |
01:50:34.94 |
-81:45:46.4 |
HIP 9052 |
20.60 |
| 2026-04-13 12:00 |
01:52:06.20 |
-81:45:41.0 |
HIP 9052 |
18.57 |
| 2026-04-14 00:00 |
01:53:37.52 |
-81:45:35.8 |
HIP 9052 |
16.96 |
| 2026-04-14 12:00 |
01:55:08.87 |
-81:45:30.9 |
HIP 9052 |
15.89 |
| 2026-04-15 00:00 |
01:56:40.27 |
-81:45:26.2 |
HIP 9052 |
15.48 |
| 2026-04-15 12:00 |
01:58:11.71 |
-81:45:21.7 |
HIP 9052 |
15.78 |
| 2026-04-16 00:00 |
01:59:43.20 |
-81:45:17.5 |
HIP 9052 |
16.76 |