| Parameter |
Value |
| Designation |
C/2025 K3 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2028-12-14T02:20:32.354880Z |
| Orbit solution date (soln_date, UTC) |
2026-09-08T09:12:17Z |
| Obs used |
97 |
| NEO |
- |
| M1 |
7.500 |
| K1 |
8.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2025-05-23T12:57:29.433600Z |
| Discovery magnitude (MPC) |
22.04 w |
| Discovery observatory (MPC) |
F52 · Pan-STARRS 2, Haleakala |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2025-12-24.0000000 |
| e |
1.00144618 |
| q (au) |
3.469750 |
| a (au) |
-2399.244855 |
| i (deg) |
104.935451 |
| Ω (om, deg) |
350.636266 |
| ω (w, deg) |
188.599849 |
| M (ma, deg) |
-0.009109 |
Magnitude
Scatter + Global Linear
$$
M_a = (7.209 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
7.209 |
| n |
6.000 |
| gf |
0.963 |
| gb |
-0.933 |
| k |
0.800 |
| 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) |
| 2026-09-20 00:00 |
16:36:04.24 |
+50:51:16.9 |
HIP 81132 |
19.41 |
| 2026-09-20 12:00 |
16:36:01.99 |
+50:47:34.8 |
HIP 81132 |
20.71 |
| 2026-09-21 00:00 |
16:35:59.93 |
+50:43:53.1 |
HIP 81132 |
22.57 |
| 2026-09-21 12:00 |
16:35:58.08 |
+50:40:11.8 |
HIP 81132 |
24.87 |
| 2026-09-22 00:00 |
16:35:56.42 |
+50:36:30.9 |
HIP 81132 |
27.48 |
| 2026-09-22 12:00 |
16:35:54.96 |
+50:32:50.6 |
HIP 81132 |
30.34 |
| 2026-09-23 00:00 |
16:35:53.69 |
+50:29:10.6 |
HIP 81239 |
30.25 |
| 2026-09-23 12:00 |
16:35:52.61 |
+50:25:31.2 |
HIP 81239 |
26.60 |
| 2026-09-24 00:00 |
16:35:51.72 |
+50:21:52.3 |
HIP 81239 |
22.96 |
| 2026-09-24 12:00 |
16:35:51.02 |
+50:18:13.8 |
HIP 81239 |
19.35 |
| 2026-09-25 00:00 |
16:35:50.51 |
+50:14:35.9 |
HIP 81239 |
15.76 |
| 2026-09-25 12:00 |
16:35:50.19 |
+50:10:58.6 |
HIP 81239 |
12.21 |
| 2026-09-26 00:00 |
16:35:50.05 |
+50:07:21.8 |
HIP 81239 |
8.74 |
| 2026-09-26 12:00 |
16:35:50.10 |
+50:03:45.5 |
HIP 81239 |
5.49 |
| 2026-09-27 00:00 |
16:35:50.33 |
+50:00:09.8 |
HIP 81239 |
3.16 |
| 2026-09-27 12:00 |
16:35:50.74 |
+49:56:34.7 |
HIP 81239 |
3.98 |
| 2026-09-28 00:00 |
16:35:51.33 |
+49:53:00.3 |
HIP 81239 |
6.89 |
| 2026-09-28 12:00 |
16:35:52.10 |
+49:49:26.4 |
HIP 81239 |
10.23 |
| 2026-09-29 00:00 |
16:35:53.06 |
+49:45:53.1 |
HIP 81239 |
13.68 |
| 2026-09-29 12:00 |
16:35:54.19 |
+49:42:20.5 |
HIP 81239 |
17.17 |
| 2026-09-30 00:00 |
16:35:55.49 |
+49:38:48.6 |
HIP 81239 |
20.68 |
| 2026-09-30 12:00 |
16:35:56.97 |
+49:35:17.3 |
HIP 81239 |
24.19 |
| 2026-10-01 00:00 |
16:35:58.63 |
+49:31:46.7 |
HIP 81135 |
25.41 |
| 2026-10-01 12:00 |
16:36:00.46 |
+49:28:16.8 |
HIP 81135 |
23.25 |
| 2026-10-02 00:00 |
16:36:02.46 |
+49:24:47.6 |
HIP 81135 |
21.49 |
| 2026-10-02 12:00 |
16:36:04.63 |
+49:21:19.1 |
HIP 81135 |
20.21 |
| 2026-10-03 00:00 |
16:36:06.97 |
+49:17:51.3 |
HIP 81135 |
19.52 |
| 2026-10-03 12:00 |
16:36:09.48 |
+49:14:24.3 |
HIP 81135 |
19.47 |
| 2026-10-04 00:00 |
16:36:12.16 |
+49:10:58.0 |
HIP 81135 |
20.05 |
| 2026-10-04 12:00 |
16:36:15.00 |
+49:07:32.5 |
HIP 81135 |
21.22 |
| 2026-10-05 00:00 |
16:36:18.01 |
+49:04:07.8 |
HIP 81135 |
22.87 |
| 2026-10-05 12:00 |
16:36:21.19 |
+49:00:43.9 |
HIP 81483 |
23.37 |
| 2026-10-06 00:00 |
16:36:24.53 |
+48:57:20.8 |
HIP 81483 |
21.77 |
| 2026-10-06 12:00 |
16:36:28.03 |
+48:53:58.5 |
HIP 81483 |
20.59 |
| 2026-10-07 00:00 |
16:36:31.69 |
+48:50:37.1 |
HIP 81483 |
19.91 |
| 2026-10-07 12:00 |
16:36:35.51 |
+48:47:16.5 |
HIP 81483 |
19.77 |
| 2026-10-08 00:00 |
16:36:39.48 |
+48:43:56.8 |
HIP 81483 |
20.18 |
| 2026-10-08 12:00 |
16:36:43.62 |
+48:40:38.0 |
HIP 81483 |
21.11 |
| 2026-10-09 00:00 |
16:36:47.91 |
+48:37:20.1 |
HIP 81195 |
20.58 |
| 2026-10-09 12:00 |
16:36:52.36 |
+48:34:03.0 |
HIP 81195 |
19.56 |
| 2026-10-10 00:00 |
16:36:56.96 |
+48:30:46.9 |
HIP 81195 |
19.11 |
| 2026-10-10 12:00 |
16:37:01.71 |
+48:27:31.7 |
HIP 81195 |
19.28 |
| 2026-10-11 00:00 |
16:37:06.61 |
+48:24:17.5 |
HIP 81195 |
20.04 |