| Parameter |
Value |
| Designation |
P/2020 WJ5 (Lemmon) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2021-07-01T10:23:55.633920Z |
| Orbit solution date (soln_date, UTC) |
2024-08-11T00:12:20Z |
| Obs used |
720 |
| NEO |
- |
| M1 |
12.300 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2022-12-17.0000000 |
| e |
0.17132992 |
| q (au) |
4.985837 |
| a (au) |
6.016673 |
| i (deg) |
22.294439 |
| Ω (om, deg) |
177.810718 |
| ω (w, deg) |
338.229837 |
| M (ma, deg) |
35.633474 |
Magnitude
Scatter + Global Linear
$$
M_a = (3.028 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
3.028 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.997 |
| k |
1.000 |
| 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
Finding Chart
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
19:51:55.86 |
+01:23:19.8 |
HIP 97762 |
12.92 |
| 2026-05-12 12:00 |
19:51:54.95 |
+01:24:35.5 |
HIP 97762 |
11.69 |
| 2026-05-13 00:00 |
19:51:53.89 |
+01:25:50.6 |
HIP 97762 |
10.49 |
| 2026-05-13 12:00 |
19:51:52.69 |
+01:27:05.1 |
HIP 97762 |
9.32 |
| 2026-05-14 00:00 |
19:51:51.35 |
+01:28:19.0 |
HIP 97762 |
8.21 |
| 2026-05-14 12:00 |
19:51:49.86 |
+01:29:32.3 |
HIP 97762 |
7.18 |
| 2026-05-15 00:00 |
19:51:48.23 |
+01:30:44.9 |
HIP 97762 |
6.26 |
| 2026-05-15 12:00 |
19:51:46.45 |
+01:31:56.9 |
HIP 97762 |
5.52 |
| 2026-05-16 00:00 |
19:51:44.53 |
+01:33:08.2 |
HIP 97762 |
5.04 |
| 2026-05-16 12:00 |
19:51:42.47 |
+01:34:18.8 |
HIP 97762 |
4.89 |
| 2026-05-17 00:00 |
19:51:40.26 |
+01:35:28.8 |
HIP 97762 |
5.12 |
| 2026-05-17 12:00 |
19:51:37.91 |
+01:36:38.1 |
HIP 97762 |
5.67 |
| 2026-05-18 00:00 |
19:51:35.42 |
+01:37:46.7 |
HIP 97762 |
6.47 |
| 2026-05-18 12:00 |
19:51:32.79 |
+01:38:54.5 |
HIP 97762 |
7.44 |
| 2026-05-19 00:00 |
19:51:30.02 |
+01:40:01.7 |
HIP 97732 |
6.72 |
| 2026-05-19 12:00 |
19:51:27.10 |
+01:41:08.2 |
HIP 97732 |
6.08 |
| 2026-05-20 00:00 |
19:51:24.05 |
+01:42:13.9 |
HIP 97732 |
5.72 |
| 2026-05-20 12:00 |
19:51:20.85 |
+01:43:19.0 |
HIP 97732 |
5.70 |
| 2026-05-21 00:00 |
19:51:17.52 |
+01:44:23.2 |
HIP 97732 |
6.02 |
| 2026-05-21 12:00 |
19:51:14.04 |
+01:45:26.8 |
HIP 97732 |
6.65 |
| 2026-05-22 00:00 |
19:51:10.43 |
+01:46:29.5 |
HIP 97732 |
7.51 |
| 2026-05-22 12:00 |
19:51:06.68 |
+01:47:31.5 |
HIP 97732 |
8.54 |
| 2026-05-23 00:00 |
19:51:02.80 |
+01:48:32.8 |
HIP 97732 |
9.70 |
| 2026-05-23 12:00 |
19:50:58.77 |
+01:49:33.3 |
HIP 97732 |
10.94 |
| 2026-05-24 00:00 |
19:50:54.61 |
+01:50:32.9 |
HIP 97732 |
12.25 |
| 2026-05-24 12:00 |
19:50:50.32 |
+01:51:31.9 |
HIP 97732 |
13.61 |
| 2026-05-25 00:00 |
19:50:45.89 |
+01:52:30.0 |
HIP 97732 |
15.02 |
| 2026-05-25 12:00 |
19:50:41.32 |
+01:53:27.3 |
HIP 97732 |
16.46 |
| 2026-05-26 00:00 |
19:50:36.62 |
+01:54:23.8 |
HIP 97732 |
17.93 |
| 2026-05-26 12:00 |
19:50:31.79 |
+01:55:19.5 |
HIP 97732 |
19.43 |
| 2026-05-27 00:00 |
19:50:26.82 |
+01:56:14.3 |
HIP 97732 |
20.95 |
| 2026-05-27 12:00 |
19:50:21.73 |
+01:57:08.4 |
HIP 97732 |
22.50 |
| 2026-05-28 00:00 |
19:50:16.50 |
+01:58:01.6 |
HIP 97732 |
24.08 |
| 2026-05-28 12:00 |
19:50:11.14 |
+01:58:54.0 |
HIP 97732 |
25.67 |
| 2026-05-29 00:00 |
19:50:05.65 |
+01:59:45.5 |
HIP 97732 |
27.29 |
| 2026-05-29 12:00 |
19:50:00.03 |
+02:00:36.1 |
HIP 97732 |
28.93 |
| 2026-05-30 00:00 |
19:49:54.28 |
+02:01:25.9 |
HIP 97732 |
30.58 |
| 2026-05-30 12:00 |
19:49:48.41 |
+02:02:14.9 |
HIP 97732 |
32.26 |
| 2026-05-31 00:00 |
19:49:42.40 |
+02:03:03.0 |
HIP 97732 |
33.96 |
| 2026-05-31 12:00 |
19:49:36.27 |
+02:03:50.1 |
HIP 97732 |
35.68 |
| 2026-06-01 00:00 |
19:49:30.01 |
+02:04:36.5 |
HIP 97418 |
36.46 |
| 2026-06-01 12:00 |
19:49:23.63 |
+02:05:21.9 |
HIP 97418 |
36.12 |
| 2026-06-02 00:00 |
19:49:17.12 |
+02:06:06.4 |
HIP 97418 |
35.83 |