P/2020 U2 (PANSTARRS)
| Parameter |
Value |
| Designation |
P/2020 U2 (PANSTARRS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2020-12-25T16:46:43.095360Z |
| Orbit solution date (soln_date, UTC) |
2021-07-01T22:13:00Z |
| Obs used |
301 |
| NEO |
- |
| M1 |
9.900 |
| K1 |
26.000 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2020-10-20T09:20:45.801600Z |
| Discovery magnitude (MPC) |
21.70 w |
| Discovery observatory (MPC) |
F51 · Pan-STARRS 1, Haleakala |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2021-01-12.0000000 |
| e |
0.51048764 |
| q (au) |
1.848825 |
| a (au) |
3.776871 |
| i (deg) |
6.420975 |
| Ω (om, deg) |
342.901523 |
| ω (w, deg) |
84.644930 |
| M (ma, deg) |
2.323134 |
Magnitude
Scatter + Global Linear
$$
M_a = (12.635 + 5.176\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
12.635 |
| n |
5.176 |
| gf |
1.000 |
| gb |
-0.500 |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-02-03 00:00 |
18:55:05.76 |
-27:55:58.4 |
HIP 92784 |
10.49 |
| 2026-02-03 12:00 |
18:55:33.26 |
-27:55:31.5 |
HIP 92927 |
13.52 |
| 2026-02-04 00:00 |
18:56:00.71 |
-27:55:04.7 |
HIP 92927 |
12.74 |
| 2026-02-04 12:00 |
18:56:28.10 |
-27:54:37.7 |
HIP 92927 |
14.68 |
| 2026-02-05 00:00 |
18:56:55.44 |
-27:54:10.8 |
HIP 93036 |
13.00 |
| 2026-02-05 12:00 |
18:57:22.71 |
-27:53:43.7 |
HIP 93036 |
13.69 |
| 2026-02-06 00:00 |
18:57:49.93 |
-27:53:16.6 |
HIP 93036 |
16.70 |
| 2026-02-06 12:00 |
18:58:17.09 |
-27:52:49.5 |
HIP 93196 |
16.55 |
| 2026-02-07 00:00 |
18:58:44.18 |
-27:52:22.3 |
HIP 93196 |
13.66 |
| 2026-02-07 12:00 |
18:59:11.22 |
-27:51:55.1 |
HIP 93196 |
13.09 |
| 2026-02-08 00:00 |
18:59:38.19 |
-27:51:27.9 |
HIP 93277 |
12.56 |
| 2026-02-08 12:00 |
19:00:05.10 |
-27:51:00.6 |
HIP 93277 |
12.08 |
| 2026-02-09 00:00 |
19:00:31.94 |
-27:50:33.3 |
HIP 93328 |
11.85 |
| 2026-02-09 12:00 |
19:00:58.72 |
-27:50:06.0 |
HIP 93328 |
12.77 |
| 2026-02-10 00:00 |
19:01:25.44 |
-27:49:38.6 |
HIP 93328 |
16.00 |
| 2026-02-10 12:00 |
19:01:52.08 |
-27:49:11.3 |
HIP 93392 |
17.92 |
| 2026-02-11 00:00 |
19:02:18.66 |
-27:48:43.9 |
HIP 93392 |
20.80 |
| 2026-02-11 12:00 |
19:02:45.17 |
-27:48:16.5 |
HIP 93392 |
24.77 |
| 2026-02-12 00:00 |
19:03:11.61 |
-27:47:49.1 |
HIP 93531 |
26.73 |
| 2026-02-12 12:00 |
19:03:37.98 |
-27:47:21.7 |
HIP 93639 |
25.62 |
| 2026-02-13 00:00 |
19:04:04.28 |
-27:46:54.3 |
HIP 93639 |
25.29 |
| 2026-02-13 12:00 |
19:04:30.50 |
-27:46:26.9 |
HIP 93639 |
26.28 |
| 2026-02-14 00:00 |
19:04:56.65 |
-27:45:59.5 |
HIP 93864 |
27.14 |
| 2026-02-14 12:00 |
19:05:22.73 |
-27:45:32.1 |
HIP 93864 |
21.42 |
| 2026-02-15 00:00 |
19:05:48.73 |
-27:45:04.7 |
HIP 93864 |
15.77 |
| 2026-02-15 12:00 |
19:06:14.65 |
-27:44:37.4 |
HIP 93864 |
10.26 |
| 2026-02-16 00:00 |
19:06:40.49 |
-27:44:10.0 |
HIP 93864 |
5.32 |
| 2026-02-16 12:00 |
19:07:06.26 |
-27:43:42.7 |
HIP 93864 |
4.14 |
| 2026-02-17 00:00 |
19:07:31.94 |
-27:43:15.5 |
HIP 93864 |
8.44 |
| 2026-02-17 12:00 |
19:07:57.55 |
-27:42:48.2 |
HIP 93864 |
13.78 |
| 2026-02-18 00:00 |
19:08:23.07 |
-27:42:21.0 |
HIP 93864 |
19.30 |
| 2026-02-18 12:00 |
19:08:48.51 |
-27:41:53.9 |
HIP 94166 |
21.83 |
| 2026-02-19 00:00 |
19:09:13.87 |
-27:41:26.8 |
HIP 94166 |
18.02 |
| 2026-02-19 12:00 |
19:09:39.14 |
-27:40:59.7 |
HIP 94166 |
15.38 |
| 2026-02-20 00:00 |
19:10:04.33 |
-27:40:32.7 |
HIP 94166 |
14.53 |
| 2026-02-20 12:00 |
19:10:29.43 |
-27:40:05.7 |
HIP 94166 |
15.75 |
| 2026-02-21 00:00 |
19:10:54.44 |
-27:39:38.9 |
HIP 94166 |
18.62 |
| 2026-02-21 12:00 |
19:11:19.37 |
-27:39:12.0 |
HIP 94411 |
21.54 |
| 2026-02-22 00:00 |
19:11:44.20 |
-27:38:45.3 |
HIP 94411 |
16.24 |
| 2026-02-22 12:00 |
19:12:08.94 |
-27:38:18.6 |
HIP 94411 |
11.16 |
| 2026-02-23 00:00 |
19:12:33.60 |
-27:37:52.0 |
HIP 94411 |
6.79 |
| 2026-02-23 12:00 |
19:12:58.16 |
-27:37:25.5 |
HIP 94411 |
5.25 |
| 2026-02-24 00:00 |
19:13:22.62 |
-27:36:59.1 |
HIP 94411 |
8.26 |