| Parameter |
Value |
| Designation |
P/2017 U3 (PANSTARRS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2019-04-21T20:05:53.658240Z |
| Orbit solution date (soln_date, UTC) |
2022-05-19T21:13:39Z |
| Obs used |
73 |
| NEO |
- |
| M1 |
14.700 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2017-08-27.0000000 |
| e |
0.09998087 |
| q (au) |
4.443406 |
| a (au) |
4.937013 |
| i (deg) |
15.908436 |
| Ω (om, deg) |
165.150002 |
| ω (w, deg) |
297.458320 |
| M (ma, deg) |
305.836360 |
Magnitude
Scatter + Global Linear
$$
M_a = (15.774 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
15.774 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.580 |
| 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
Finding Chart
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
22:29:23.91 |
-04:11:29.9 |
HIP 111009 |
0.22 |
| 2026-05-12 12:00 |
22:29:38.27 |
-04:10:17.1 |
HIP 111009 |
3.77 |
| 2026-05-13 00:00 |
22:29:52.51 |
-04:09:04.9 |
HIP 111009 |
7.51 |
| 2026-05-13 12:00 |
22:30:06.62 |
-04:07:53.5 |
HIP 111009 |
11.23 |
| 2026-05-14 00:00 |
22:30:20.61 |
-04:06:42.7 |
HIP 111009 |
14.91 |
| 2026-05-14 12:00 |
22:30:34.46 |
-04:05:32.6 |
HIP 111009 |
18.56 |
| 2026-05-15 00:00 |
22:30:48.19 |
-04:04:23.3 |
HIP 111238 |
21.06 |
| 2026-05-15 12:00 |
22:31:01.79 |
-04:03:14.7 |
HIP 111238 |
17.67 |
| 2026-05-16 00:00 |
22:31:15.26 |
-04:02:06.8 |
HIP 111238 |
14.40 |
| 2026-05-16 12:00 |
22:31:28.60 |
-04:00:59.6 |
HIP 111238 |
11.32 |
| 2026-05-17 00:00 |
22:31:41.81 |
-03:59:53.2 |
HIP 111238 |
8.60 |
| 2026-05-17 12:00 |
22:31:54.89 |
-03:58:47.5 |
HIP 111238 |
6.65 |
| 2026-05-18 00:00 |
22:32:07.83 |
-03:57:42.6 |
HIP 111238 |
6.17 |
| 2026-05-18 12:00 |
22:32:20.64 |
-03:56:38.5 |
HIP 111238 |
7.39 |
| 2026-05-19 00:00 |
22:32:33.32 |
-03:55:35.1 |
HIP 111238 |
9.67 |
| 2026-05-19 12:00 |
22:32:45.87 |
-03:54:32.6 |
HIP 111238 |
12.40 |
| 2026-05-20 00:00 |
22:32:58.27 |
-03:53:30.8 |
HIP 111238 |
15.32 |
| 2026-05-20 12:00 |
22:33:10.55 |
-03:52:29.8 |
HIP 111238 |
18.32 |
| 2026-05-21 00:00 |
22:33:22.68 |
-03:51:29.6 |
HIP 111238 |
21.35 |
| 2026-05-21 12:00 |
22:33:34.68 |
-03:50:30.2 |
HIP 111454 |
22.23 |
| 2026-05-22 00:00 |
22:33:46.54 |
-03:49:31.6 |
HIP 111454 |
19.39 |
| 2026-05-22 12:00 |
22:33:58.27 |
-03:48:33.8 |
HIP 111454 |
16.68 |
| 2026-05-23 00:00 |
22:34:09.85 |
-03:47:36.8 |
HIP 111454 |
14.16 |
| 2026-05-23 12:00 |
22:34:21.30 |
-03:46:40.7 |
HIP 111454 |
11.90 |
| 2026-05-24 00:00 |
22:34:32.60 |
-03:45:45.4 |
HIP 111454 |
10.07 |
| 2026-05-24 12:00 |
22:34:43.77 |
-03:44:51.0 |
HIP 111454 |
8.89 |
| 2026-05-25 00:00 |
22:34:54.80 |
-03:43:57.4 |
HIP 111454 |
8.59 |
| 2026-05-25 12:00 |
22:35:05.68 |
-03:43:04.6 |
HIP 111454 |
9.23 |
| 2026-05-26 00:00 |
22:35:16.42 |
-03:42:12.7 |
HIP 111454 |
10.60 |
| 2026-05-26 12:00 |
22:35:27.02 |
-03:41:21.7 |
HIP 111454 |
12.44 |
| 2026-05-27 00:00 |
22:35:37.48 |
-03:40:31.5 |
HIP 111454 |
14.55 |
| 2026-05-27 12:00 |
22:35:47.80 |
-03:39:42.2 |
HIP 111454 |
16.81 |
| 2026-05-28 00:00 |
22:35:57.97 |
-03:38:53.8 |
HIP 111454 |
19.15 |
| 2026-05-28 12:00 |
22:36:07.99 |
-03:38:06.3 |
HIP 111454 |
21.53 |
| 2026-05-29 00:00 |
22:36:17.87 |
-03:37:19.7 |
HIP 111454 |
23.93 |
| 2026-05-29 12:00 |
22:36:27.61 |
-03:36:33.9 |
HIP 111454 |
26.33 |
| 2026-05-30 00:00 |
22:36:37.19 |
-03:35:49.1 |
HIP 111454 |
28.71 |
| 2026-05-30 12:00 |
22:36:46.64 |
-03:35:05.2 |
HIP 111454 |
31.08 |
| 2026-05-31 00:00 |
22:36:55.93 |
-03:34:22.2 |
HIP 111454 |
33.43 |
| 2026-05-31 12:00 |
22:37:05.07 |
-03:33:40.1 |
HIP 111840 |
32.68 |
| 2026-06-01 00:00 |
22:37:14.07 |
-03:32:59.0 |
HIP 111840 |
30.51 |
| 2026-06-01 12:00 |
22:37:22.92 |
-03:32:18.8 |
HIP 111840 |
28.41 |
| 2026-06-02 00:00 |
22:37:31.62 |
-03:31:39.5 |
HIP 111840 |
26.38 |