| Parameter |
Value |
| Designation |
C/2023 H3 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2024-02-18T22:29:26.165760Z |
| Orbit solution date (soln_date, UTC) |
2026-04-27T13:42:19Z |
| Obs used |
82 |
| NEO |
- |
| M1 |
14.000 |
| K1 |
4.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2023-04-28T09:29:59.020800Z |
| Discovery magnitude (MPC) |
20.89 w |
| Discovery observatory (MPC) |
F52 · Pan-STARRS 2, Haleakala |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2023-12-27.0000000 |
| e |
0.61615996 |
| q (au) |
5.232462 |
| a (au) |
13.631882 |
| i (deg) |
2.489026 |
| Ω (om, deg) |
55.102514 |
| ω (w, deg) |
193.320297 |
| M (ma, deg) |
358.943771 |
Magnitude
Scatter + Global Linear
$$
M_a = (12.936 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
12.936 |
| n |
2.000 |
| gf |
0.997 |
| gb |
-0.935 |
| 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
Finding Chart
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-06-01 00:00 |
22:00:57.07 |
-14:54:00.7 |
HIP 108522 |
30.24 |
| 2026-06-01 12:00 |
22:01:00.13 |
-14:53:56.2 |
HIP 108522 |
30.93 |
| 2026-06-02 00:00 |
22:01:03.07 |
-14:53:52.5 |
HIP 108522 |
31.58 |
| 2026-06-02 12:00 |
22:01:05.87 |
-14:53:49.4 |
HIP 108522 |
32.20 |
| 2026-06-03 00:00 |
22:01:08.53 |
-14:53:47.1 |
HIP 108882 |
32.66 |
| 2026-06-03 12:00 |
22:01:11.07 |
-14:53:45.4 |
HIP 108882 |
32.05 |
| 2026-06-04 00:00 |
22:01:13.47 |
-14:53:44.5 |
HIP 108882 |
31.48 |
| 2026-06-04 12:00 |
22:01:15.73 |
-14:53:44.2 |
HIP 108882 |
30.93 |
| 2026-06-05 00:00 |
22:01:17.86 |
-14:53:44.7 |
HIP 108882 |
30.42 |
| 2026-06-05 12:00 |
22:01:19.86 |
-14:53:45.9 |
HIP 108882 |
29.94 |
| 2026-06-06 00:00 |
22:01:21.73 |
-14:53:47.8 |
HIP 108882 |
29.49 |
| 2026-06-06 12:00 |
22:01:23.46 |
-14:53:50.3 |
HIP 108882 |
29.07 |
| 2026-06-07 00:00 |
22:01:25.05 |
-14:53:53.6 |
HIP 108882 |
28.68 |
| 2026-06-07 12:00 |
22:01:26.52 |
-14:53:57.6 |
HIP 108882 |
28.32 |
| 2026-06-08 00:00 |
22:01:27.84 |
-14:54:02.3 |
HIP 108882 |
27.99 |
| 2026-06-08 12:00 |
22:01:29.04 |
-14:54:07.7 |
HIP 108882 |
27.70 |
| 2026-06-09 00:00 |
22:01:30.09 |
-14:54:13.8 |
HIP 108882 |
27.43 |
| 2026-06-09 12:00 |
22:01:31.02 |
-14:54:20.6 |
HIP 108882 |
27.20 |
| 2026-06-10 00:00 |
22:01:31.81 |
-14:54:28.1 |
HIP 108882 |
27.00 |
| 2026-06-10 12:00 |
22:01:32.46 |
-14:54:36.3 |
HIP 108882 |
26.82 |
| 2026-06-11 00:00 |
22:01:32.98 |
-14:54:45.2 |
HIP 108882 |
26.69 |
| 2026-06-11 12:00 |
22:01:33.37 |
-14:54:54.8 |
HIP 108882 |
26.58 |
| 2026-06-12 00:00 |
22:01:33.62 |
-14:55:05.1 |
HIP 108882 |
26.50 |
| 2026-06-12 12:00 |
22:01:33.74 |
-14:55:16.1 |
HIP 108882 |
26.46 |
| 2026-06-13 00:00 |
22:01:33.72 |
-14:55:27.8 |
HIP 108882 |
26.45 |
| 2026-06-13 12:00 |
22:01:33.57 |
-14:55:40.2 |
HIP 108882 |
26.48 |
| 2026-06-14 00:00 |
22:01:33.29 |
-14:55:53.2 |
HIP 108882 |
26.54 |
| 2026-06-14 12:00 |
22:01:32.87 |
-14:56:07.0 |
HIP 108882 |
26.63 |
| 2026-06-15 00:00 |
22:01:32.32 |
-14:56:21.4 |
HIP 108882 |
26.75 |
| 2026-06-15 12:00 |
22:01:31.63 |
-14:56:36.6 |
HIP 108882 |
26.91 |
| 2026-06-16 00:00 |
22:01:30.81 |
-14:56:52.4 |
HIP 108882 |
27.11 |
| 2026-06-16 12:00 |
22:01:29.86 |
-14:57:08.9 |
HIP 108882 |
27.33 |
| 2026-06-17 00:00 |
22:01:28.78 |
-14:57:26.0 |
HIP 108882 |
27.60 |
| 2026-06-17 12:00 |
22:01:27.56 |
-14:57:43.9 |
HIP 108882 |
27.90 |
| 2026-06-18 00:00 |
22:01:26.21 |
-14:58:02.4 |
HIP 108882 |
28.23 |
| 2026-06-18 12:00 |
22:01:24.73 |
-14:58:21.5 |
HIP 108882 |
28.60 |
| 2026-06-19 00:00 |
22:01:23.12 |
-14:58:41.3 |
HIP 108882 |
29.00 |
| 2026-06-19 12:00 |
22:01:21.38 |
-14:59:01.8 |
HIP 108882 |
29.44 |
| 2026-06-20 00:00 |
22:01:19.51 |
-14:59:23.0 |
HIP 108882 |
29.92 |
| 2026-06-20 12:00 |
22:01:17.51 |
-14:59:44.8 |
HIP 108882 |
30.43 |
| 2026-06-21 00:00 |
22:01:15.38 |
-15:00:07.2 |
HIP 108882 |
30.98 |
| 2026-06-21 12:00 |
22:01:13.12 |
-15:00:30.3 |
HIP 108522 |
31.41 |
| 2026-06-22 00:00 |
22:01:10.73 |
-15:00:54.0 |
HIP 108522 |
30.75 |