| 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) |
| 2026-05-12 00:00 |
03:19:54.17 |
-81:46:12.6 |
HIP 15470 |
1.47 |
| 2026-05-12 12:00 |
03:21:27.63 |
-81:46:18.0 |
HIP 15470 |
4.45 |
| 2026-05-13 00:00 |
03:23:01.12 |
-81:46:23.5 |
HIP 15470 |
7.74 |
| 2026-05-13 12:00 |
03:24:34.63 |
-81:46:29.1 |
HIP 15470 |
11.07 |
| 2026-05-14 00:00 |
03:26:08.18 |
-81:46:34.9 |
HIP 15470 |
14.40 |
| 2026-05-14 12:00 |
03:27:41.75 |
-81:46:40.8 |
HIP 15470 |
17.75 |
| 2026-05-15 00:00 |
03:29:15.34 |
-81:46:46.8 |
HIP 15470 |
21.09 |
| 2026-05-15 12:00 |
03:30:48.95 |
-81:46:53.0 |
HIP 17184 |
21.41 |
| 2026-05-16 00:00 |
03:32:22.59 |
-81:46:59.3 |
HIP 17184 |
18.06 |
| 2026-05-16 12:00 |
03:33:56.25 |
-81:47:05.7 |
HIP 17184 |
14.72 |
| 2026-05-17 00:00 |
03:35:29.93 |
-81:47:12.3 |
HIP 17184 |
11.37 |
| 2026-05-17 12:00 |
03:37:03.63 |
-81:47:19.0 |
HIP 17184 |
8.02 |
| 2026-05-18 00:00 |
03:38:37.34 |
-81:47:25.8 |
HIP 17184 |
4.67 |
| 2026-05-18 12:00 |
03:40:11.07 |
-81:47:32.7 |
HIP 17184 |
1.34 |
| 2026-05-19 00:00 |
03:41:44.81 |
-81:47:39.8 |
HIP 17184 |
2.04 |
| 2026-05-19 12:00 |
03:43:18.57 |
-81:47:47.0 |
HIP 17184 |
5.38 |
| 2026-05-20 00:00 |
03:44:52.33 |
-81:47:54.3 |
HIP 17184 |
8.72 |
| 2026-05-20 12:00 |
03:46:26.11 |
-81:48:01.7 |
HIP 17184 |
12.07 |
| 2026-05-21 00:00 |
03:47:59.89 |
-81:48:09.2 |
HIP 17184 |
15.42 |
| 2026-05-21 12:00 |
03:49:33.69 |
-81:48:16.9 |
HIP 17184 |
18.76 |
| 2026-05-22 00:00 |
03:51:07.48 |
-81:48:24.6 |
HIP 17184 |
22.11 |
| 2026-05-22 12:00 |
03:52:41.29 |
-81:48:32.5 |
HIP 17184 |
25.45 |
| 2026-05-23 00:00 |
03:54:15.09 |
-81:48:40.5 |
HIP 17184 |
28.79 |
| 2026-05-23 12:00 |
03:55:48.90 |
-81:48:48.6 |
HIP 18136 |
31.73 |
| 2026-05-24 00:00 |
03:57:22.71 |
-81:48:56.8 |
HIP 18136 |
32.43 |
| 2026-05-24 12:00 |
03:58:56.53 |
-81:49:05.0 |
HIP 18136 |
33.42 |
| 2026-05-25 00:00 |
04:00:30.34 |
-81:49:13.4 |
HIP 18136 |
34.68 |
| 2026-05-25 12:00 |
04:02:04.15 |
-81:49:21.9 |
HIP 18136 |
36.18 |
| 2026-05-26 00:00 |
04:03:37.96 |
-81:49:30.5 |
HIP 18136 |
37.90 |
| 2026-05-26 12:00 |
04:05:11.77 |
-81:49:39.2 |
HIP 20382 |
35.80 |
| 2026-05-27 00:00 |
04:06:45.57 |
-81:49:47.9 |
HIP 20382 |
32.47 |
| 2026-05-27 12:00 |
04:08:19.37 |
-81:49:56.8 |
HIP 20382 |
29.16 |
| 2026-05-28 00:00 |
04:09:53.16 |
-81:50:05.8 |
HIP 20382 |
25.86 |
| 2026-05-28 12:00 |
04:11:26.95 |
-81:50:14.8 |
HIP 20382 |
22.57 |
| 2026-05-29 00:00 |
04:13:00.73 |
-81:50:23.9 |
HIP 20382 |
19.30 |
| 2026-05-29 12:00 |
04:14:34.50 |
-81:50:33.2 |
HIP 20382 |
16.07 |
| 2026-05-30 00:00 |
04:16:08.26 |
-81:50:42.5 |
HIP 20382 |
12.89 |
| 2026-05-30 12:00 |
04:17:42.01 |
-81:50:51.9 |
HIP 20382 |
9.83 |
| 2026-05-31 00:00 |
04:19:15.75 |
-81:51:01.3 |
HIP 20382 |
7.04 |
| 2026-05-31 12:00 |
04:20:49.48 |
-81:51:10.9 |
HIP 20382 |
4.97 |
| 2026-06-01 00:00 |
04:22:23.20 |
-81:51:20.6 |
HIP 20382 |
4.71 |
| 2026-06-01 12:00 |
04:23:56.90 |
-81:51:30.3 |
HIP 20382 |
6.48 |
| 2026-06-02 00:00 |
04:25:30.59 |
-81:51:40.1 |
HIP 20382 |
9.17 |