| Parameter |
Value |
| Designation |
P/2019 U4 (PANSTARRS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2019-09-18T08:38:38.333760Z |
| Orbit solution date (soln_date, UTC) |
2021-11-09T14:03:17Z |
| Obs used |
53 |
| NEO |
- |
| M1 |
18.600 |
| K1 |
10.000 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2019-10-25T12:45:41.212800Z |
| Discovery magnitude (MPC) |
21.11 w |
| Discovery observatory (MPC) |
F51 · Pan-STARRS 1, Haleakala |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2019-10-19.0000000 |
| e |
0.47518301 |
| q (au) |
1.847129 |
| a (au) |
3.519568 |
| i (deg) |
11.692289 |
| Ω (om, deg) |
200.040609 |
| ω (w, deg) |
180.960217 |
| M (ma, deg) |
4.573581 |
Magnitude
Scatter + Global Linear
$$
M_a = (19.329 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
19.329 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.681 |
| 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) |
| 2026-09-20 00:00 |
07:08:50.75 |
+12:42:52.7 |
HIP 34604 |
20.54 |
| 2026-09-20 12:00 |
07:09:35.71 |
+12:39:13.2 |
HIP 34604 |
9.43 |
| 2026-09-21 00:00 |
07:10:20.40 |
+12:35:33.0 |
HIP 34604 |
4.74 |
| 2026-09-21 12:00 |
07:11:04.82 |
+12:31:52.1 |
HIP 34604 |
14.79 |
| 2026-09-22 00:00 |
07:11:48.96 |
+12:28:10.4 |
HIP 34823 |
10.16 |
| 2026-09-22 12:00 |
07:12:32.82 |
+12:24:28.0 |
HIP 34823 |
7.60 |
| 2026-09-23 00:00 |
07:13:16.41 |
+12:20:45.0 |
HIP 34823 |
16.36 |
| 2026-09-23 12:00 |
07:13:59.73 |
+12:17:01.2 |
HIP 35005 |
12.89 |
| 2026-09-24 00:00 |
07:14:42.76 |
+12:13:16.8 |
HIP 35005 |
6.79 |
| 2026-09-24 12:00 |
07:15:25.51 |
+12:09:31.8 |
HIP 35005 |
13.17 |
| 2026-09-25 00:00 |
07:16:07.98 |
+12:05:46.1 |
HIP 35234 |
11.24 |
| 2026-09-25 12:00 |
07:16:50.17 |
+12:01:59.8 |
HIP 35234 |
4.64 |
| 2026-09-26 00:00 |
07:17:32.08 |
+11:58:12.9 |
HIP 35234 |
12.52 |
| 2026-09-26 12:00 |
07:18:13.70 |
+11:54:25.3 |
HIP 35234 |
22.98 |
| 2026-09-27 00:00 |
07:18:55.04 |
+11:50:37.3 |
HIP 35234 |
33.64 |
| 2026-09-27 12:00 |
07:19:36.09 |
+11:46:48.6 |
HIP 35758 |
43.45 |
| 2026-09-28 00:00 |
07:20:16.85 |
+11:42:59.4 |
HIP 35758 |
34.13 |
| 2026-09-28 12:00 |
07:20:57.33 |
+11:39:09.7 |
HIP 35758 |
25.94 |
| 2026-09-29 00:00 |
07:21:37.51 |
+11:35:19.4 |
HIP 35758 |
20.21 |
| 2026-09-29 12:00 |
07:22:17.39 |
+11:31:28.6 |
HIP 35758 |
19.17 |
| 2026-09-30 00:00 |
07:22:56.99 |
+11:27:37.4 |
HIP 35758 |
23.38 |
| 2026-09-30 12:00 |
07:23:36.29 |
+11:23:45.6 |
HIP 35987 |
25.92 |
| 2026-10-01 00:00 |
07:24:15.29 |
+11:19:53.5 |
HIP 35987 |
22.84 |
| 2026-10-01 12:00 |
07:24:53.99 |
+11:16:00.8 |
HIP 36048 |
18.75 |
| 2026-10-02 00:00 |
07:25:32.40 |
+11:12:07.8 |
HIP 36048 |
18.09 |
| 2026-10-02 12:00 |
07:26:10.50 |
+11:08:14.3 |
HIP 36141 |
10.78 |
| 2026-10-03 00:00 |
07:26:48.30 |
+11:04:20.4 |
HIP 36141 |
4.19 |
| 2026-10-03 12:00 |
07:27:25.79 |
+11:00:26.2 |
HIP 36141 |
10.94 |
| 2026-10-04 00:00 |
07:28:02.97 |
+10:56:31.5 |
HIP 36385 |
19.09 |
| 2026-10-04 12:00 |
07:28:39.85 |
+10:52:36.6 |
HIP 36385 |
12.91 |
| 2026-10-05 00:00 |
07:29:16.41 |
+10:48:41.3 |
HIP 36385 |
12.79 |
| 2026-10-05 12:00 |
07:29:52.67 |
+10:44:45.7 |
HIP 36385 |
18.74 |
| 2026-10-06 00:00 |
07:30:28.60 |
+10:40:49.8 |
HIP 36385 |
26.94 |
| 2026-10-06 12:00 |
07:31:04.23 |
+10:36:53.7 |
HIP 36606 |
33.74 |
| 2026-10-07 00:00 |
07:31:39.53 |
+10:32:57.3 |
HIP 36606 |
28.54 |
| 2026-10-07 12:00 |
07:32:14.51 |
+10:29:00.6 |
HIP 36606 |
25.91 |
| 2026-10-08 00:00 |
07:32:49.18 |
+10:25:03.8 |
HIP 36796 |
20.70 |
| 2026-10-08 12:00 |
07:33:23.52 |
+10:21:06.7 |
HIP 36796 |
16.50 |
| 2026-10-09 00:00 |
07:33:57.53 |
+10:17:09.5 |
HIP 36796 |
17.03 |
| 2026-10-09 12:00 |
07:34:31.22 |
+10:13:12.1 |
HIP 36900 |
11.68 |
| 2026-10-10 00:00 |
07:35:04.58 |
+10:09:14.5 |
HIP 36900 |
2.76 |
| 2026-10-10 12:00 |
07:35:37.61 |
+10:05:16.9 |
HIP 36900 |
6.63 |
| 2026-10-11 00:00 |
07:36:10.31 |
+10:01:19.1 |
HIP 36900 |
15.54 |