| Parameter |
Value |
| Designation |
P/2021 L2 (Leonard) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2021-07-24T13:05:37.386240Z |
| Orbit solution date (soln_date, UTC) |
2021-11-20T19:13:06Z |
| Obs used |
131 |
| NEO |
- |
| M1 |
16.200 |
| K1 |
11.500 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2021-06-08T09:29:49.689600Z |
| Discovery magnitude (MPC) |
20.31 G |
| Discovery observatory (MPC) |
G96 · University of Arizona Mt. Lemmon Survey |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2021-07-26.0000000 |
| e |
0.52175163 |
| q (au) |
1.938550 |
| a (au) |
4.053438 |
| i (deg) |
21.068982 |
| Ω (om, deg) |
266.675736 |
| ω (w, deg) |
51.538655 |
| M (ma, deg) |
0.175655 |
Magnitude
Scatter + Global Linear
$$
M_a = (18.492 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
18.492 |
| n |
2.000 |
| gf |
0.800 |
| gb |
-1.000 |
| k |
0.965 |
| δ90 |
1.000 |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-06-01 00:00 |
09:06:45.42 |
-02:23:58.6 |
HIP 44696 |
12.63 |
| 2026-06-01 12:00 |
09:06:57.60 |
-02:23:49.0 |
HIP 44696 |
14.01 |
| 2026-06-02 00:00 |
09:07:09.89 |
-02:23:40.4 |
HIP 44820 |
13.80 |
| 2026-06-02 12:00 |
09:07:22.28 |
-02:23:32.7 |
HIP 44820 |
11.02 |
| 2026-06-03 00:00 |
09:07:34.79 |
-02:23:26.0 |
HIP 44820 |
8.43 |
| 2026-06-03 12:00 |
09:07:47.40 |
-02:23:20.1 |
HIP 44820 |
6.31 |
| 2026-06-04 00:00 |
09:08:00.11 |
-02:23:15.2 |
HIP 44820 |
5.33 |
| 2026-06-04 12:00 |
09:08:12.94 |
-02:23:11.2 |
HIP 44820 |
6.09 |
| 2026-06-05 00:00 |
09:08:25.86 |
-02:23:08.2 |
HIP 44820 |
8.15 |
| 2026-06-05 12:00 |
09:08:38.89 |
-02:23:06.0 |
HIP 44820 |
10.81 |
| 2026-06-06 00:00 |
09:08:52.02 |
-02:23:04.8 |
HIP 44937 |
9.45 |
| 2026-06-06 12:00 |
09:09:05.26 |
-02:23:04.6 |
HIP 44937 |
8.12 |
| 2026-06-07 00:00 |
09:09:18.60 |
-02:23:05.2 |
HIP 44937 |
8.06 |
| 2026-06-07 12:00 |
09:09:32.03 |
-02:23:06.8 |
HIP 44937 |
9.30 |
| 2026-06-08 00:00 |
09:09:45.57 |
-02:23:09.3 |
HIP 44937 |
11.45 |
| 2026-06-08 12:00 |
09:09:59.21 |
-02:23:12.7 |
HIP 44937 |
14.13 |
| 2026-06-09 00:00 |
09:10:12.95 |
-02:23:17.1 |
HIP 44937 |
17.10 |
| 2026-06-09 12:00 |
09:10:26.78 |
-02:23:22.4 |
HIP 44937 |
20.24 |
| 2026-06-10 00:00 |
09:10:40.71 |
-02:23:28.6 |
HIP 45142 |
19.98 |
| 2026-06-10 12:00 |
09:10:54.74 |
-02:23:35.7 |
HIP 45142 |
17.03 |
| 2026-06-11 00:00 |
09:11:08.86 |
-02:23:43.8 |
HIP 45142 |
14.32 |
| 2026-06-11 12:00 |
09:11:23.08 |
-02:23:52.8 |
HIP 45142 |
12.05 |
| 2026-06-12 00:00 |
09:11:37.40 |
-02:24:02.7 |
HIP 45142 |
10.52 |
| 2026-06-12 12:00 |
09:11:51.81 |
-02:24:13.6 |
HIP 45142 |
10.11 |
| 2026-06-13 00:00 |
09:12:06.31 |
-02:24:25.3 |
HIP 45142 |
10.96 |
| 2026-06-13 12:00 |
09:12:20.90 |
-02:24:38.0 |
HIP 45142 |
12.85 |
| 2026-06-14 00:00 |
09:12:35.59 |
-02:24:51.7 |
HIP 45267 |
14.23 |
| 2026-06-14 12:00 |
09:12:50.36 |
-02:25:06.2 |
HIP 45267 |
10.59 |
| 2026-06-15 00:00 |
09:13:05.23 |
-02:25:21.7 |
HIP 45267 |
7.00 |
| 2026-06-15 12:00 |
09:13:20.18 |
-02:25:38.1 |
HIP 45267 |
3.67 |
| 2026-06-16 00:00 |
09:13:35.22 |
-02:25:55.4 |
HIP 45267 |
2.46 |
| 2026-06-16 12:00 |
09:13:50.35 |
-02:26:13.7 |
HIP 45267 |
5.22 |
| 2026-06-17 00:00 |
09:14:05.57 |
-02:26:32.8 |
HIP 45267 |
8.82 |
| 2026-06-17 12:00 |
09:14:20.87 |
-02:26:52.9 |
HIP 45267 |
12.57 |
| 2026-06-18 00:00 |
09:14:36.26 |
-02:27:13.9 |
HIP 45267 |
16.38 |
| 2026-06-18 12:00 |
09:14:51.73 |
-02:27:35.9 |
HIP 45267 |
20.23 |
| 2026-06-19 00:00 |
09:15:07.28 |
-02:27:58.7 |
HIP 45267 |
24.12 |
| 2026-06-19 12:00 |
09:15:22.92 |
-02:28:22.4 |
HIP 45267 |
28.03 |
| 2026-06-20 00:00 |
09:15:38.63 |
-02:28:47.1 |
HIP 45267 |
31.97 |
| 2026-06-20 12:00 |
09:15:54.43 |
-02:29:12.6 |
HIP 45267 |
35.94 |
| 2026-06-21 00:00 |
09:16:10.31 |
-02:29:39.1 |
HIP 45267 |
39.92 |
| 2026-06-21 12:00 |
09:16:26.27 |
-02:30:06.5 |
HIP 45710 |
40.37 |
| 2026-06-22 00:00 |
09:16:42.30 |
-02:30:34.7 |
HIP 45710 |
36.41 |