| Parameter |
Value |
| Designation |
P/2021 P3 (PANSTARRS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2021-05-31T00:59:23.956800Z |
| Orbit solution date (soln_date, UTC) |
2024-04-13T16:42:58Z |
| Obs used |
104 |
| NEO |
- |
| M1 |
13.700 |
| K1 |
10.000 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2021-08-11T14:01:45.033600Z |
| Discovery magnitude (MPC) |
20.63 w |
| Discovery observatory (MPC) |
F51 · Pan-STARRS 1, Haleakala |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2021-09-09.0000000 |
| e |
0.34046368 |
| q (au) |
2.916288 |
| a (au) |
4.421724 |
| i (deg) |
27.156308 |
| Ω (om, deg) |
358.237092 |
| ω (w, deg) |
334.236786 |
| M (ma, deg) |
10.701892 |
Magnitude
Scatter + Global Linear
$$
M_a = (14.341 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
14.341 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.755 |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-09-20 00:00 |
11:26:31.02 |
+08:40:03.2 |
HIP 55816 |
3.24 |
| 2026-09-20 12:00 |
11:26:50.84 |
+08:37:16.8 |
HIP 55816 |
8.43 |
| 2026-09-21 00:00 |
11:27:10.65 |
+08:34:30.6 |
HIP 55816 |
13.96 |
| 2026-09-21 12:00 |
11:27:30.45 |
+08:31:44.5 |
HIP 55985 |
13.95 |
| 2026-09-22 00:00 |
11:27:50.23 |
+08:28:58.6 |
HIP 55985 |
9.81 |
| 2026-09-22 12:00 |
11:28:10.01 |
+08:26:12.9 |
HIP 55985 |
7.80 |
| 2026-09-23 00:00 |
11:28:29.77 |
+08:23:27.3 |
HIP 55985 |
9.41 |
| 2026-09-23 12:00 |
11:28:49.52 |
+08:20:41.9 |
HIP 55985 |
13.38 |
| 2026-09-24 00:00 |
11:29:09.25 |
+08:17:56.6 |
HIP 55985 |
18.23 |
| 2026-09-24 12:00 |
11:29:28.97 |
+08:15:11.5 |
HIP 55985 |
23.41 |
| 2026-09-25 00:00 |
11:29:48.67 |
+08:12:26.6 |
HIP 55985 |
28.75 |
| 2026-09-25 12:00 |
11:30:08.36 |
+08:09:41.8 |
HIP 56234 |
28.88 |
| 2026-09-26 00:00 |
11:30:28.03 |
+08:06:57.2 |
HIP 56234 |
23.37 |
| 2026-09-26 12:00 |
11:30:47.69 |
+08:04:12.8 |
HIP 56234 |
17.92 |
| 2026-09-27 00:00 |
11:31:07.32 |
+08:01:28.6 |
HIP 56234 |
12.60 |
| 2026-09-27 12:00 |
11:31:26.94 |
+07:58:44.6 |
HIP 56234 |
7.64 |
| 2026-09-28 00:00 |
11:31:46.54 |
+07:56:00.7 |
HIP 56234 |
4.50 |
| 2026-09-28 12:00 |
11:32:06.13 |
+07:53:17.1 |
HIP 56234 |
6.65 |
| 2026-09-29 00:00 |
11:32:25.69 |
+07:50:33.6 |
HIP 56234 |
11.40 |
| 2026-09-29 12:00 |
11:32:45.23 |
+07:47:50.4 |
HIP 56386 |
15.92 |
| 2026-09-30 00:00 |
11:33:04.76 |
+07:45:07.3 |
HIP 56386 |
15.20 |
| 2026-09-30 12:00 |
11:33:24.26 |
+07:42:24.4 |
HIP 56386 |
16.44 |
| 2026-10-01 00:00 |
11:33:43.74 |
+07:39:41.8 |
HIP 56355 |
17.52 |
| 2026-10-01 12:00 |
11:34:03.19 |
+07:36:59.3 |
HIP 56355 |
18.52 |
| 2026-10-02 00:00 |
11:34:22.63 |
+07:34:17.1 |
HIP 56355 |
20.97 |
| 2026-10-02 12:00 |
11:34:42.04 |
+07:31:35.1 |
HIP 56355 |
24.45 |
| 2026-10-03 00:00 |
11:35:01.43 |
+07:28:53.3 |
HIP 56355 |
28.57 |
| 2026-10-03 12:00 |
11:35:20.79 |
+07:26:11.7 |
HIP 56355 |
33.09 |
| 2026-10-04 00:00 |
11:35:40.13 |
+07:23:30.4 |
HIP 56574 |
37.63 |
| 2026-10-04 12:00 |
11:35:59.44 |
+07:20:49.3 |
HIP 56574 |
34.74 |
| 2026-10-05 00:00 |
11:36:18.73 |
+07:18:08.4 |
HIP 56574 |
32.52 |
| 2026-10-05 12:00 |
11:36:37.98 |
+07:15:27.7 |
HIP 56574 |
31.13 |
| 2026-10-06 00:00 |
11:36:57.21 |
+07:12:47.3 |
HIP 56812 |
29.28 |
| 2026-10-06 12:00 |
11:37:16.41 |
+07:10:07.2 |
HIP 56812 |
26.21 |
| 2026-10-07 00:00 |
11:37:35.59 |
+07:07:27.3 |
HIP 56812 |
24.01 |
| 2026-10-07 12:00 |
11:37:54.73 |
+07:04:47.7 |
HIP 56812 |
22.92 |
| 2026-10-08 00:00 |
11:38:13.84 |
+07:02:08.3 |
HIP 56812 |
23.09 |
| 2026-10-08 12:00 |
11:38:32.92 |
+06:59:29.2 |
HIP 56812 |
24.50 |
| 2026-10-09 00:00 |
11:38:51.96 |
+06:56:50.3 |
HIP 56812 |
26.93 |
| 2026-10-09 12:00 |
11:39:10.98 |
+06:54:11.8 |
HIP 56787 |
25.98 |
| 2026-10-10 00:00 |
11:39:29.96 |
+06:51:33.5 |
HIP 56787 |
25.81 |
| 2026-10-10 12:00 |
11:39:48.90 |
+06:48:55.5 |
HIP 56787 |
26.74 |
| 2026-10-11 00:00 |
11:40:07.81 |
+06:46:17.8 |
HIP 57071 |
27.26 |