| 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) |
| 2026-07-29 00:00 |
03:09:15.62 |
+03:48:22.3 |
HIP 14746 |
32.24 |
| 2026-07-29 12:00 |
03:09:52.59 |
+03:48:48.8 |
HIP 14746 |
27.92 |
| 2026-07-30 00:00 |
03:10:29.41 |
+03:49:13.5 |
HIP 14746 |
26.28 |
| 2026-07-30 12:00 |
03:11:06.07 |
+03:49:36.6 |
HIP 14937 |
23.91 |
| 2026-07-31 00:00 |
03:11:42.58 |
+03:49:58.0 |
HIP 14937 |
15.46 |
| 2026-07-31 12:00 |
03:12:18.92 |
+03:50:17.7 |
HIP 14937 |
8.56 |
| 2026-08-01 00:00 |
03:12:55.11 |
+03:50:35.7 |
HIP 14992 |
4.76 |
| 2026-08-01 12:00 |
03:13:31.14 |
+03:50:52.1 |
HIP 14992 |
4.68 |
| 2026-08-02 00:00 |
03:14:07.00 |
+03:51:06.8 |
HIP 14992 |
13.48 |
| 2026-08-02 12:00 |
03:14:42.70 |
+03:51:19.7 |
HIP 15169 |
16.60 |
| 2026-08-03 00:00 |
03:15:18.23 |
+03:51:31.0 |
HIP 15169 |
11.59 |
| 2026-08-03 12:00 |
03:15:53.59 |
+03:51:40.6 |
HIP 15169 |
12.27 |
| 2026-08-04 00:00 |
03:16:28.78 |
+03:51:48.4 |
HIP 15169 |
17.94 |
| 2026-08-04 12:00 |
03:17:03.80 |
+03:51:54.6 |
HIP 15333 |
15.12 |
| 2026-08-05 00:00 |
03:17:38.64 |
+03:51:59.0 |
HIP 15333 |
11.21 |
| 2026-08-05 12:00 |
03:18:13.31 |
+03:52:01.7 |
HIP 15333 |
13.14 |
| 2026-08-06 00:00 |
03:18:47.79 |
+03:52:02.7 |
HIP 15443 |
16.12 |
| 2026-08-06 12:00 |
03:19:22.10 |
+03:52:02.0 |
HIP 15443 |
16.09 |
| 2026-08-07 00:00 |
03:19:56.22 |
+03:51:59.5 |
HIP 15628 |
19.41 |
| 2026-08-07 12:00 |
03:20:30.16 |
+03:51:55.3 |
HIP 15628 |
10.95 |
| 2026-08-08 00:00 |
03:21:03.90 |
+03:51:49.4 |
HIP 15628 |
2.55 |
| 2026-08-08 12:00 |
03:21:37.46 |
+03:51:41.7 |
HIP 15628 |
5.86 |
| 2026-08-09 00:00 |
03:22:10.83 |
+03:51:32.3 |
HIP 15628 |
14.17 |
| 2026-08-09 12:00 |
03:22:44.00 |
+03:51:21.1 |
HIP 15628 |
22.45 |
| 2026-08-10 00:00 |
03:23:16.97 |
+03:51:08.2 |
HIP 15872 |
17.48 |
| 2026-08-10 12:00 |
03:23:49.75 |
+03:50:53.6 |
HIP 15872 |
9.35 |
| 2026-08-11 00:00 |
03:24:22.32 |
+03:50:37.2 |
HIP 15872 |
1.72 |
| 2026-08-11 12:00 |
03:24:54.69 |
+03:50:19.1 |
HIP 15872 |
7.08 |
| 2026-08-12 00:00 |
03:25:26.86 |
+03:49:59.2 |
HIP 15872 |
15.05 |
| 2026-08-12 12:00 |
03:25:58.81 |
+03:49:37.6 |
HIP 15872 |
23.01 |
| 2026-08-13 00:00 |
03:26:30.56 |
+03:49:14.2 |
HIP 16066 |
22.30 |
| 2026-08-13 12:00 |
03:27:02.09 |
+03:48:49.1 |
HIP 16066 |
20.99 |
| 2026-08-14 00:00 |
03:27:33.41 |
+03:48:22.2 |
HIP 16066 |
22.49 |
| 2026-08-14 12:00 |
03:28:04.51 |
+03:47:53.6 |
HIP 16155 |
21.30 |
| 2026-08-15 00:00 |
03:28:35.39 |
+03:47:23.3 |
HIP 16155 |
22.58 |
| 2026-08-15 12:00 |
03:29:06.06 |
+03:46:51.2 |
HIP 16346 |
24.47 |
| 2026-08-16 00:00 |
03:29:36.50 |
+03:46:17.4 |
HIP 16346 |
17.76 |
| 2026-08-16 12:00 |
03:30:06.71 |
+03:45:41.9 |
HIP 16346 |
12.22 |
| 2026-08-17 00:00 |
03:30:36.70 |
+03:45:04.6 |
HIP 16346 |
9.92 |
| 2026-08-17 12:00 |
03:31:06.46 |
+03:44:25.6 |
HIP 16346 |
12.64 |
| 2026-08-18 00:00 |
03:31:35.99 |
+03:43:44.9 |
HIP 16479 |
12.63 |
| 2026-08-18 12:00 |
03:32:05.28 |
+03:43:02.4 |
HIP 16479 |
9.73 |
| 2026-08-19 00:00 |
03:32:34.34 |
+03:42:18.2 |
HIP 16479 |
11.73 |