C/2022 R3 (Leonard)
Metadata
| Parameter | Value |
|---|---|
| Designation | C/2022 R3 (Leonard) |
| Type | C |
| Perihelion (tp_cal, UTC) | 2023-03-05T07:22:22.114560Z |
| Orbit solution date (soln_date, UTC) | 2025-04-11T14:44:29Z |
| Obs used | 355 |
| NEO | - |
| M1 | 12.300 |
| K1 | 4.500 |
| PC | - |
| Discovery observation (MPC, UTC) | 2022-09-15T08:35:14.697600Z |
| Discovery magnitude (MPC) | 18.96 G |
| Discovery observatory (MPC) | G96 · University of Arizona Mt. Lemmon Survey |
Osculating Elements
| Parameter | Value |
|---|---|
| Epoch (epoch_cal, TDB) | 2023-08-01.0000000 |
| e | 1.00075876 |
| q (au) | 5.128952 |
| a (au) | -6759.666695 |
| i (deg) | 43.082904 |
| Ω (om, deg) | 8.238598 |
| ω (w, deg) | 72.866685 |
| M (ma, deg) | 0.000264 |
Magnitude
Scatter + Global Linear
$$ M_a = (16.040 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
Model Parameters
| Parameter | Value |
|---|---|
| H0 | 16.040 |
| n | 2.000 |
| gf | 1.000 |
| gb | -0.844 |
| 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 |
|---|---|---|---|
| 2023-08-17 | 2024-05-13 | -12.5844 | +9.340 |
| 2024-05-13 | 2026-02-25 | -19.7422 | +16.108 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Finding Chart
Ephemeris
| Date/Time (UTC) | RA (J2000) | Dec (J2000) | Nearest HIP | Dist from HIP (arcmin) |
|---|---|---|---|---|
| 2026-07-29 00:00 | 11:44:10.03 | +14:13:14.8 | HIP 57320 | 15.10 |
| 2026-07-29 12:00 | 11:44:18.46 | +14:11:19.3 | HIP 57320 | 13.60 |
| 2026-07-30 00:00 | 11:44:26.94 | +14:09:23.7 | HIP 57320 | 12.55 |
| 2026-07-30 12:00 | 11:44:35.47 | +14:07:28.0 | HIP 57320 | 12.06 |
| 2026-07-31 00:00 | 11:44:44.04 | +14:05:32.4 | HIP 57320 | 12.22 |
| 2026-07-31 12:00 | 11:44:52.67 | +14:03:36.6 | HIP 57320 | 13.01 |
| 2026-08-01 00:00 | 11:45:01.34 | +14:01:40.9 | HIP 57320 | 14.33 |
| 2026-08-01 12:00 | 11:45:10.07 | +13:59:45.1 | HIP 57320 | 16.05 |
| 2026-08-02 00:00 | 11:45:18.84 | +13:57:49.2 | HIP 57320 | 18.07 |
| 2026-08-02 12:00 | 11:45:27.65 | +13:55:53.4 | HIP 57428 | 17.81 |
| 2026-08-03 00:00 | 11:45:36.52 | +13:53:57.5 | HIP 57379 | 17.16 |
| 2026-08-03 12:00 | 11:45:45.43 | +13:52:01.5 | HIP 57379 | 14.94 |
| 2026-08-04 00:00 | 11:45:54.38 | +13:50:05.6 | HIP 57442 | 12.57 |
| 2026-08-04 12:00 | 11:46:03.38 | +13:48:09.6 | HIP 57442 | 9.66 |
| 2026-08-05 00:00 | 11:46:12.43 | +13:46:13.6 | HIP 57442 | 6.74 |
| 2026-08-05 12:00 | 11:46:21.52 | +13:44:17.6 | HIP 57442 | 3.83 |
| 2026-08-06 00:00 | 11:46:30.65 | +13:42:21.6 | HIP 57442 | 1.05 |
| 2026-08-06 12:00 | 11:46:39.83 | +13:40:25.5 | HIP 57442 | 2.21 |
| 2026-08-07 00:00 | 11:46:49.05 | +13:38:29.5 | HIP 57442 | 5.12 |
| 2026-08-07 12:00 | 11:46:58.31 | +13:36:33.4 | HIP 57442 | 8.07 |
| 2026-08-08 00:00 | 11:47:07.62 | +13:34:37.4 | HIP 57442 | 11.04 |
| 2026-08-08 12:00 | 11:47:16.97 | +13:32:41.3 | HIP 57527 | 9.79 |
| 2026-08-09 00:00 | 11:47:26.35 | +13:30:45.2 | HIP 57527 | 7.58 |
| 2026-08-09 12:00 | 11:47:35.78 | +13:28:49.2 | HIP 57527 | 6.08 |
| 2026-08-10 00:00 | 11:47:45.25 | +13:26:53.2 | HIP 57527 | 5.88 |
| 2026-08-10 12:00 | 11:47:54.76 | +13:24:57.1 | HIP 57527 | 7.10 |
| 2026-08-11 00:00 | 11:48:04.31 | +13:23:01.1 | HIP 57527 | 9.20 |
| 2026-08-11 12:00 | 11:48:13.89 | +13:21:05.1 | HIP 57527 | 11.72 |
| 2026-08-12 00:00 | 11:48:23.52 | +13:19:09.1 | HIP 57527 | 14.45 |
| 2026-08-12 12:00 | 11:48:33.18 | +13:17:13.2 | HIP 57527 | 17.28 |
| 2026-08-13 00:00 | 11:48:42.88 | +13:15:17.3 | HIP 57527 | 20.19 |
| 2026-08-13 12:00 | 11:48:52.61 | +13:13:21.4 | HIP 57527 | 23.14 |
| 2026-08-14 00:00 | 11:49:02.39 | +13:11:25.5 | HIP 57721 | 20.51 |
| 2026-08-14 12:00 | 11:49:12.19 | +13:09:29.7 | HIP 57721 | 17.47 |
| 2026-08-15 00:00 | 11:49:22.03 | +13:07:33.9 | HIP 57721 | 14.44 |
| 2026-08-15 12:00 | 11:49:31.91 | +13:05:38.2 | HIP 57721 | 11.43 |
| 2026-08-16 00:00 | 11:49:41.82 | +13:03:42.5 | HIP 57721 | 8.46 |
| 2026-08-16 12:00 | 11:49:51.76 | +13:01:46.9 | HIP 57721 | 5.62 |
| 2026-08-17 00:00 | 11:50:01.74 | +12:59:51.4 | HIP 57721 | 3.25 |
| 2026-08-17 12:00 | 11:50:11.75 | +12:57:55.8 | HIP 57721 | 2.97 |
| 2026-08-18 00:00 | 11:50:21.79 | +12:56:00.4 | HIP 57721 | 5.13 |
| 2026-08-18 12:00 | 11:50:31.86 | +12:54:05.0 | HIP 57721 | 7.96 |
| 2026-08-19 00:00 | 11:50:41.96 | +12:52:09.7 | HIP 57721 | 10.94 |