C/2022 W3 (Leonard)
| 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) |
| 2026-02-03 00:00 |
22:22:53.13 |
-82:42:40.4 |
HIP 110231 |
7.66 |
| 2026-02-03 12:00 |
22:24:25.01 |
-82:41:56.8 |
HIP 110231 |
9.81 |
| 2026-02-04 00:00 |
22:25:56.83 |
-82:41:13.4 |
HIP 110231 |
12.33 |
| 2026-02-04 12:00 |
22:27:28.58 |
-82:40:30.3 |
HIP 110231 |
15.05 |
| 2026-02-05 00:00 |
22:29:00.27 |
-82:39:47.4 |
HIP 110231 |
17.87 |
| 2026-02-05 12:00 |
22:30:31.90 |
-82:39:04.8 |
HIP 111825 |
18.80 |
| 2026-02-06 00:00 |
22:32:03.48 |
-82:38:22.4 |
HIP 111825 |
16.83 |
| 2026-02-06 12:00 |
22:33:34.99 |
-82:37:40.2 |
HIP 111825 |
15.18 |
| 2026-02-07 00:00 |
22:35:06.45 |
-82:36:58.2 |
HIP 111825 |
13.98 |
| 2026-02-07 12:00 |
22:36:37.85 |
-82:36:16.5 |
HIP 111825 |
13.34 |
| 2026-02-08 00:00 |
22:38:09.20 |
-82:35:35.0 |
HIP 111825 |
13.34 |
| 2026-02-08 12:00 |
22:39:40.50 |
-82:34:53.8 |
HIP 111825 |
13.99 |
| 2026-02-09 00:00 |
22:41:11.74 |
-82:34:12.8 |
HIP 111825 |
15.20 |
| 2026-02-09 12:00 |
22:42:42.93 |
-82:33:32.0 |
HIP 111825 |
16.86 |
| 2026-02-10 00:00 |
22:44:14.08 |
-82:32:51.6 |
HIP 112911 |
17.53 |
| 2026-02-10 12:00 |
22:45:45.17 |
-82:32:11.3 |
HIP 112911 |
15.55 |
| 2026-02-11 00:00 |
22:47:16.21 |
-82:31:31.3 |
HIP 112911 |
13.94 |
| 2026-02-11 12:00 |
22:48:47.21 |
-82:30:51.6 |
HIP 112911 |
12.82 |
| 2026-02-12 00:00 |
22:50:18.16 |
-82:30:12.1 |
HIP 112911 |
12.34 |
| 2026-02-12 12:00 |
22:51:49.06 |
-82:29:32.9 |
HIP 112911 |
12.58 |
| 2026-02-13 00:00 |
22:53:19.92 |
-82:28:53.9 |
HIP 112911 |
13.49 |
| 2026-02-13 12:00 |
22:54:50.73 |
-82:28:15.2 |
HIP 112911 |
14.95 |
| 2026-02-14 00:00 |
22:56:21.50 |
-82:27:36.7 |
HIP 112911 |
16.82 |
| 2026-02-14 12:00 |
22:57:52.23 |
-82:26:58.6 |
HIP 113807 |
18.18 |
| 2026-02-15 00:00 |
22:59:22.92 |
-82:26:20.7 |
HIP 113807 |
17.42 |
| 2026-02-15 12:00 |
23:00:53.56 |
-82:25:43.0 |
HIP 113807 |
17.15 |
| 2026-02-16 00:00 |
23:02:24.17 |
-82:25:05.7 |
HIP 113807 |
17.39 |
| 2026-02-16 12:00 |
23:03:54.73 |
-82:24:28.6 |
HIP 113807 |
18.13 |
| 2026-02-17 00:00 |
23:05:25.26 |
-82:23:51.7 |
HIP 113807 |
19.30 |
| 2026-02-17 12:00 |
23:06:55.74 |
-82:23:15.2 |
HIP 113807 |
20.84 |
| 2026-02-18 00:00 |
23:08:26.19 |
-82:22:38.9 |
HIP 113807 |
22.67 |
| 2026-02-18 12:00 |
23:09:56.60 |
-82:22:03.0 |
HIP 113807 |
24.73 |
| 2026-02-19 00:00 |
23:11:26.98 |
-82:21:27.3 |
HIP 113807 |
26.96 |
| 2026-02-19 12:00 |
23:12:57.32 |
-82:20:51.9 |
HIP 113807 |
29.33 |
| 2026-02-20 00:00 |
23:14:27.62 |
-82:20:16.7 |
HIP 113807 |
31.81 |
| 2026-02-20 12:00 |
23:15:57.89 |
-82:19:41.9 |
HIP 113807 |
34.37 |
| 2026-02-21 00:00 |
23:17:28.12 |
-82:19:07.3 |
HIP 115970 |
34.61 |
| 2026-02-21 12:00 |
23:18:58.32 |
-82:18:33.0 |
HIP 115970 |
32.01 |
| 2026-02-22 00:00 |
23:20:28.49 |
-82:17:59.1 |
HIP 115970 |
29.52 |
| 2026-02-22 12:00 |
23:21:58.63 |
-82:17:25.4 |
HIP 115970 |
27.17 |
| 2026-02-23 00:00 |
23:23:28.73 |
-82:16:52.0 |
HIP 115970 |
24.98 |
| 2026-02-23 12:00 |
23:24:58.80 |
-82:16:18.8 |
HIP 115970 |
23.03 |
| 2026-02-24 00:00 |
23:26:28.84 |
-82:15:46.0 |
HIP 115970 |
21.36 |