| Parameter |
Value |
| Designation |
500P/PANSTARRS |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2025-02-23T01:30:16.018560Z |
| Orbit solution date (soln_date, UTC) |
2026-03-11T21:13:03Z |
| Obs used |
87 |
| NEO |
- |
| M1 |
14.300 |
| K1 |
16.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2019-01-11T15:21:07.488000Z |
| Discovery magnitude (MPC) |
21.50 w |
| Discovery observatory (MPC) |
F51 · Pan-STARRS 1, Haleakala |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2022-06-16.0000000 |
| e |
0.41335657 |
| q (au) |
1.968866 |
| a (au) |
3.356155 |
| i (deg) |
2.381049 |
| Ω (om, deg) |
116.500219 |
| ω (w, deg) |
42.292781 |
| M (ma, deg) |
202.412297 |
Magnitude
Scatter + Global Linear
$$
M_a = (14.441 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
14.441 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-1.000 |
| 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) |
| 2026-09-20 00:00 |
17:50:06.52 |
-23:04:32.6 |
HIP 87329 |
7.77 |
| 2026-09-20 12:00 |
17:50:24.08 |
-23:04:48.3 |
HIP 87329 |
4.14 |
| 2026-09-21 00:00 |
17:50:41.85 |
-23:05:03.8 |
HIP 87329 |
2.60 |
| 2026-09-21 12:00 |
17:50:59.83 |
-23:05:19.1 |
HIP 87329 |
5.51 |
| 2026-09-22 00:00 |
17:51:18.02 |
-23:05:34.3 |
HIP 87329 |
9.45 |
| 2026-09-22 12:00 |
17:51:36.42 |
-23:05:49.4 |
HIP 87370 |
12.47 |
| 2026-09-23 00:00 |
17:51:55.02 |
-23:06:04.3 |
HIP 87370 |
15.35 |
| 2026-09-23 12:00 |
17:52:13.82 |
-23:06:19.1 |
HIP 87370 |
18.81 |
| 2026-09-24 00:00 |
17:52:32.82 |
-23:06:33.7 |
HIP 87370 |
22.62 |
| 2026-09-24 12:00 |
17:52:52.03 |
-23:06:48.1 |
HIP 87668 |
22.85 |
| 2026-09-25 00:00 |
17:53:11.43 |
-23:07:02.4 |
HIP 87668 |
18.59 |
| 2026-09-25 12:00 |
17:53:31.03 |
-23:07:16.5 |
HIP 87668 |
14.41 |
| 2026-09-26 00:00 |
17:53:50.83 |
-23:07:30.4 |
HIP 87668 |
10.49 |
| 2026-09-26 12:00 |
17:54:10.82 |
-23:07:44.1 |
HIP 87668 |
7.33 |
| 2026-09-27 00:00 |
17:54:31.00 |
-23:07:57.7 |
HIP 87668 |
6.30 |
| 2026-09-27 12:00 |
17:54:51.38 |
-23:08:11.0 |
HIP 87668 |
8.33 |
| 2026-09-28 00:00 |
17:55:11.94 |
-23:08:24.2 |
HIP 87774 |
8.79 |
| 2026-09-28 12:00 |
17:55:32.70 |
-23:08:37.2 |
HIP 87774 |
4.08 |
| 2026-09-29 00:00 |
17:55:53.64 |
-23:08:49.9 |
HIP 87774 |
1.31 |
| 2026-09-29 12:00 |
17:56:14.76 |
-23:09:02.5 |
HIP 87774 |
5.81 |
| 2026-09-30 00:00 |
17:56:36.07 |
-23:09:14.9 |
HIP 87893 |
8.61 |
| 2026-09-30 12:00 |
17:56:57.57 |
-23:09:27.0 |
HIP 87893 |
3.70 |
| 2026-10-01 00:00 |
17:57:19.25 |
-23:09:38.9 |
HIP 87893 |
1.52 |
| 2026-10-01 12:00 |
17:57:41.10 |
-23:09:50.6 |
HIP 87893 |
6.42 |
| 2026-10-02 00:00 |
17:58:03.14 |
-23:10:02.1 |
HIP 87893 |
11.47 |
| 2026-10-02 12:00 |
17:58:25.36 |
-23:10:13.3 |
HIP 87942 |
13.50 |
| 2026-10-03 00:00 |
17:58:47.75 |
-23:10:24.3 |
HIP 87942 |
16.82 |
| 2026-10-03 12:00 |
17:59:10.32 |
-23:10:35.0 |
HIP 87942 |
20.92 |
| 2026-10-04 00:00 |
17:59:33.07 |
-23:10:45.5 |
HIP 87942 |
25.47 |
| 2026-10-04 12:00 |
17:59:55.99 |
-23:10:55.7 |
HIP 87942 |
30.27 |
| 2026-10-05 00:00 |
18:00:19.08 |
-23:11:05.7 |
HIP 88330 |
29.94 |
| 2026-10-05 12:00 |
18:00:42.34 |
-23:11:15.5 |
HIP 88330 |
24.96 |
| 2026-10-06 00:00 |
18:01:05.77 |
-23:11:24.9 |
HIP 88330 |
20.13 |
| 2026-10-06 12:00 |
18:01:29.38 |
-23:11:34.1 |
HIP 88330 |
15.63 |
| 2026-10-07 00:00 |
18:01:53.15 |
-23:11:43.0 |
HIP 88330 |
11.92 |
| 2026-10-07 12:00 |
18:02:17.08 |
-23:11:51.7 |
HIP 88330 |
9.96 |
| 2026-10-08 00:00 |
18:02:41.18 |
-23:12:00.0 |
HIP 88330 |
10.83 |
| 2026-10-08 12:00 |
18:03:05.45 |
-23:12:08.1 |
HIP 88330 |
14.05 |
| 2026-10-09 00:00 |
18:03:29.88 |
-23:12:15.8 |
HIP 88330 |
18.46 |
| 2026-10-09 12:00 |
18:03:54.47 |
-23:12:23.3 |
HIP 88333 |
23.41 |
| 2026-10-10 00:00 |
18:04:19.22 |
-23:12:30.4 |
HIP 88597 |
19.55 |
| 2026-10-10 12:00 |
18:04:44.13 |
-23:12:37.3 |
HIP 88597 |
15.57 |
| 2026-10-11 00:00 |
18:05:09.19 |
-23:12:43.8 |
HIP 88597 |
12.96 |