| Parameter |
Value |
| Designation |
P/2019 A4 (PANSTARRS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2018-12-05T05:23:53.433600Z |
| Orbit solution date (soln_date, UTC) |
2022-06-07T21:45:21Z |
| Obs used |
85 |
| NEO |
- |
| M1 |
15.500 |
| K1 |
10.000 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2019-01-10T08:46:05.376000Z |
| Discovery magnitude (MPC) |
20.60 w |
| Discovery observatory (MPC) |
F51 · Pan-STARRS 1, Haleakala |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2019-01-18.0000000 |
| e |
0.08960737 |
| q (au) |
2.379288 |
| a (au) |
2.613474 |
| i (deg) |
13.318898 |
| Ω (om, deg) |
119.300120 |
| ω (w, deg) |
341.836468 |
| M (ma, deg) |
10.211830 |
Magnitude
Scatter + Global Linear
$$
M_a = (13.420 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
13.420 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.849 |
| k |
0.999 |
| 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) |
| 2026-06-01 00:00 |
01:46:05.51 |
+00:07:39.9 |
HIP 8274 |
8.15 |
| 2026-06-01 12:00 |
01:46:52.27 |
+00:10:48.2 |
HIP 8274 |
5.43 |
| 2026-06-02 00:00 |
01:47:38.99 |
+00:13:55.6 |
HIP 8341 |
4.68 |
| 2026-06-02 12:00 |
01:48:25.67 |
+00:17:01.8 |
HIP 8393 |
10.33 |
| 2026-06-03 00:00 |
01:49:12.32 |
+00:20:07.0 |
HIP 8393 |
15.49 |
| 2026-06-03 12:00 |
01:49:58.93 |
+00:23:11.1 |
HIP 8393 |
25.77 |
| 2026-06-04 00:00 |
01:50:45.49 |
+00:26:14.2 |
HIP 8639 |
25.10 |
| 2026-06-04 12:00 |
01:51:32.02 |
+00:29:16.1 |
HIP 8639 |
20.06 |
| 2026-06-05 00:00 |
01:52:18.51 |
+00:32:17.0 |
HIP 8815 |
17.93 |
| 2026-06-05 12:00 |
01:53:04.96 |
+00:35:16.8 |
HIP 8815 |
13.31 |
| 2026-06-06 00:00 |
01:53:51.37 |
+00:38:15.5 |
HIP 8815 |
17.89 |
| 2026-06-06 12:00 |
01:54:37.74 |
+00:41:13.0 |
HIP 8952 |
11.19 |
| 2026-06-07 00:00 |
01:55:24.07 |
+00:44:09.5 |
HIP 8952 |
7.77 |
| 2026-06-07 12:00 |
01:56:10.35 |
+00:47:04.8 |
HIP 8952 |
16.74 |
| 2026-06-08 00:00 |
01:56:56.59 |
+00:49:59.0 |
HIP 9205 |
22.72 |
| 2026-06-08 12:00 |
01:57:42.79 |
+00:52:52.0 |
HIP 9205 |
13.01 |
| 2026-06-09 00:00 |
01:58:28.94 |
+00:55:43.9 |
HIP 9205 |
10.26 |
| 2026-06-09 12:00 |
01:59:15.05 |
+00:58:34.7 |
HIP 9205 |
17.97 |
| 2026-06-10 00:00 |
02:00:01.11 |
+01:01:24.3 |
HIP 9205 |
28.66 |
| 2026-06-10 12:00 |
02:00:47.12 |
+01:04:12.7 |
HIP 9457 |
20.94 |
| 2026-06-11 00:00 |
02:01:33.09 |
+01:07:00.0 |
HIP 9457 |
13.68 |
| 2026-06-11 12:00 |
02:02:19.01 |
+01:09:46.0 |
HIP 9457 |
14.68 |
| 2026-06-12 00:00 |
02:03:04.88 |
+01:12:30.8 |
HIP 9457 |
22.85 |
| 2026-06-12 12:00 |
02:03:50.70 |
+01:15:14.5 |
HIP 9612 |
21.80 |
| 2026-06-13 00:00 |
02:04:36.47 |
+01:17:56.9 |
HIP 9612 |
24.42 |
| 2026-06-13 12:00 |
02:05:22.19 |
+01:20:38.1 |
HIP 9856 |
22.31 |
| 2026-06-14 00:00 |
02:06:07.86 |
+01:23:18.1 |
HIP 9856 |
10.61 |
| 2026-06-14 12:00 |
02:06:53.47 |
+01:25:56.9 |
HIP 9856 |
1.42 |
| 2026-06-15 00:00 |
02:07:39.03 |
+01:28:34.4 |
HIP 9856 |
12.84 |
| 2026-06-15 12:00 |
02:08:24.53 |
+01:31:10.7 |
HIP 9856 |
24.50 |
| 2026-06-16 00:00 |
02:09:09.98 |
+01:33:45.7 |
HIP 9986 |
23.48 |
| 2026-06-16 12:00 |
02:09:55.37 |
+01:36:19.5 |
HIP 10217 |
22.32 |
| 2026-06-17 00:00 |
02:10:40.71 |
+01:38:52.0 |
HIP 10217 |
10.71 |
| 2026-06-17 12:00 |
02:11:25.98 |
+01:41:23.2 |
HIP 10217 |
0.92 |
| 2026-06-18 00:00 |
02:12:11.20 |
+01:43:53.2 |
HIP 10217 |
12.46 |
| 2026-06-18 12:00 |
02:12:56.35 |
+01:46:21.9 |
HIP 10412 |
22.74 |
| 2026-06-19 00:00 |
02:13:41.45 |
+01:48:49.3 |
HIP 10445 |
16.10 |
| 2026-06-19 12:00 |
02:14:26.48 |
+01:51:15.4 |
HIP 10445 |
10.92 |
| 2026-06-20 00:00 |
02:15:11.46 |
+01:53:40.2 |
HIP 10445 |
15.60 |
| 2026-06-20 12:00 |
02:15:56.37 |
+01:56:03.7 |
HIP 10664 |
19.77 |
| 2026-06-21 00:00 |
02:16:41.21 |
+01:58:26.0 |
HIP 10664 |
10.55 |
| 2026-06-21 12:00 |
02:17:26.00 |
+02:00:46.9 |
HIP 10664 |
9.67 |
| 2026-06-22 00:00 |
02:18:10.71 |
+02:03:06.5 |
HIP 10723 |
17.85 |