| 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
$$
M_a = (14.441 + 5.999\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
14.441 |
| n |
5.999 |
| gf |
0.997 |
| gb |
-1.000 |
| k |
1.000 |
| δ90 |
9.991 |
| 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) |
| 2026-05-12 00:00 |
18:36:42.69 |
-21:51:05.0 |
HIP 91304 |
23.75 |
| 2026-05-12 12:00 |
18:36:32.50 |
-21:51:17.9 |
HIP 91130 |
21.89 |
| 2026-05-13 00:00 |
18:36:21.98 |
-21:51:31.1 |
HIP 91130 |
19.94 |
| 2026-05-13 12:00 |
18:36:11.12 |
-21:51:44.6 |
HIP 91130 |
18.05 |
| 2026-05-14 00:00 |
18:35:59.94 |
-21:51:58.5 |
HIP 91130 |
16.29 |
| 2026-05-14 12:00 |
18:35:48.42 |
-21:52:12.7 |
HIP 91130 |
14.74 |
| 2026-05-15 00:00 |
18:35:36.58 |
-21:52:27.3 |
HIP 91130 |
13.53 |
| 2026-05-15 12:00 |
18:35:24.41 |
-21:52:42.2 |
HIP 91130 |
12.79 |
| 2026-05-16 00:00 |
18:35:11.93 |
-21:52:57.4 |
HIP 91130 |
12.65 |
| 2026-05-16 12:00 |
18:34:59.12 |
-21:53:13.0 |
HIP 91130 |
13.20 |
| 2026-05-17 00:00 |
18:34:45.99 |
-21:53:28.8 |
HIP 91130 |
14.40 |
| 2026-05-17 12:00 |
18:34:32.55 |
-21:53:45.0 |
HIP 91130 |
16.14 |
| 2026-05-18 00:00 |
18:34:18.80 |
-21:54:01.5 |
HIP 91130 |
18.30 |
| 2026-05-18 12:00 |
18:34:04.73 |
-21:54:18.3 |
HIP 91130 |
20.80 |
| 2026-05-19 00:00 |
18:33:50.36 |
-21:54:35.3 |
HIP 91046 |
22.50 |
| 2026-05-19 12:00 |
18:33:35.69 |
-21:54:52.7 |
HIP 90872 |
20.86 |
| 2026-05-20 00:00 |
18:33:20.71 |
-21:55:10.3 |
HIP 90872 |
17.61 |
| 2026-05-20 12:00 |
18:33:05.43 |
-21:55:28.2 |
HIP 90872 |
14.40 |
| 2026-05-21 00:00 |
18:32:49.86 |
-21:55:46.4 |
HIP 90872 |
11.35 |
| 2026-05-21 12:00 |
18:32:33.99 |
-21:56:04.8 |
HIP 90872 |
8.70 |
| 2026-05-22 00:00 |
18:32:17.84 |
-21:56:23.5 |
HIP 90872 |
7.04 |
| 2026-05-22 12:00 |
18:32:01.39 |
-21:56:42.4 |
HIP 90872 |
7.22 |
| 2026-05-23 00:00 |
18:31:44.67 |
-21:57:01.6 |
HIP 90872 |
9.20 |
| 2026-05-23 12:00 |
18:31:27.67 |
-21:57:21.0 |
HIP 90872 |
12.20 |
| 2026-05-24 00:00 |
18:31:10.39 |
-21:57:40.6 |
HIP 90872 |
15.69 |
| 2026-05-24 12:00 |
18:30:52.83 |
-21:58:00.4 |
HIP 90872 |
19.44 |
| 2026-05-25 00:00 |
18:30:35.01 |
-21:58:20.4 |
HIP 90631 |
18.68 |
| 2026-05-25 12:00 |
18:30:16.92 |
-21:58:40.6 |
HIP 90631 |
15.51 |
| 2026-05-26 00:00 |
18:29:58.57 |
-21:59:01.0 |
HIP 90631 |
12.90 |
| 2026-05-26 12:00 |
18:29:39.96 |
-21:59:21.6 |
HIP 90631 |
11.34 |
| 2026-05-27 00:00 |
18:29:21.09 |
-21:59:42.3 |
HIP 90631 |
11.34 |
| 2026-05-27 12:00 |
18:29:01.97 |
-22:00:03.2 |
HIP 90631 |
12.95 |
| 2026-05-28 00:00 |
18:28:42.61 |
-22:00:24.3 |
HIP 90631 |
15.73 |
| 2026-05-28 12:00 |
18:28:23.00 |
-22:00:45.5 |
HIP 90631 |
19.23 |
| 2026-05-29 00:00 |
18:28:03.15 |
-22:01:06.8 |
HIP 90631 |
23.14 |
| 2026-05-29 12:00 |
18:27:43.06 |
-22:01:28.3 |
HIP 90631 |
27.33 |
| 2026-05-30 00:00 |
18:27:22.74 |
-22:01:49.9 |
HIP 90451 |
29.95 |
| 2026-05-30 12:00 |
18:27:02.19 |
-22:02:11.6 |
HIP 90451 |
29.97 |
| 2026-05-31 00:00 |
18:26:41.42 |
-22:02:33.4 |
HIP 90451 |
30.75 |
| 2026-05-31 12:00 |
18:26:20.42 |
-22:02:55.3 |
HIP 90451 |
32.27 |
| 2026-06-01 00:00 |
18:25:59.21 |
-22:03:17.3 |
HIP 90451 |
34.44 |
| 2026-06-01 12:00 |
18:25:37.79 |
-22:03:39.4 |
HIP 90130 |
37.15 |
| 2026-06-02 00:00 |
18:25:16.16 |
-22:04:01.6 |
HIP 90130 |
33.71 |