| Parameter |
Value |
| Designation |
C/2025 M2 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2027-11-23T12:06:14.215680Z |
| Orbit solution date (soln_date, UTC) |
2026-10-01T13:12:08Z |
| Obs used |
619 |
| NEO |
- |
| M1 |
5.100 |
| K1 |
11.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2025-06-22T12:55:09.638400Z |
| Discovery magnitude (MPC) |
20.66 w |
| Discovery observatory (MPC) |
F52 · Pan-STARRS 2, Haleakala |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2026-03-27.0000000 |
| e |
1.00191748 |
| q (au) |
2.720935 |
| a (au) |
-1419.016154 |
| i (deg) |
173.215316 |
| Ω (om, deg) |
305.534130 |
| ω (w, deg) |
96.754581 |
| M (ma, deg) |
-0.011183 |
Magnitude
Scatter + Global Linear
$$
M_a = (4.850 + 4.973\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
4.850 |
| n |
4.973 |
| gf |
0.886 |
| gb |
-0.500 |
| k |
0.869 |
| δ90 |
3.944 |
| 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) |
| 2026-09-25 00:00 |
18:49:46.35 |
-21:23:12.0 |
HIP 92242 |
36.03 |
| 2026-09-25 12:00 |
18:49:27.44 |
-21:23:24.9 |
HIP 92242 |
33.22 |
| 2026-09-26 00:00 |
18:49:08.80 |
-21:23:37.4 |
HIP 92242 |
30.81 |
| 2026-09-26 12:00 |
18:48:50.44 |
-21:23:49.5 |
HIP 92242 |
28.88 |
| 2026-09-27 00:00 |
18:48:32.34 |
-21:24:01.1 |
HIP 92242 |
27.51 |
| 2026-09-27 12:00 |
18:48:14.51 |
-21:24:12.4 |
HIP 92242 |
26.74 |
| 2026-09-28 00:00 |
18:47:56.94 |
-21:24:23.3 |
HIP 92242 |
26.59 |
| 2026-09-28 12:00 |
18:47:39.65 |
-21:24:33.8 |
HIP 92242 |
27.07 |
| 2026-09-29 00:00 |
18:47:22.62 |
-21:24:43.9 |
HIP 92242 |
28.09 |
| 2026-09-29 12:00 |
18:47:05.86 |
-21:24:53.6 |
HIP 92242 |
29.58 |
| 2026-09-30 00:00 |
18:46:49.36 |
-21:25:02.9 |
HIP 92242 |
31.46 |
| 2026-09-30 12:00 |
18:46:33.13 |
-21:25:11.9 |
HIP 91998 |
28.95 |
| 2026-10-01 00:00 |
18:46:17.16 |
-21:25:20.5 |
HIP 91998 |
26.31 |
| 2026-10-01 12:00 |
18:46:01.46 |
-21:25:28.8 |
HIP 91998 |
23.99 |
| 2026-10-02 00:00 |
18:45:46.02 |
-21:25:36.7 |
HIP 91998 |
22.07 |
| 2026-10-02 12:00 |
18:45:30.85 |
-21:25:44.3 |
HIP 91998 |
20.62 |
| 2026-10-03 00:00 |
18:45:15.93 |
-21:25:51.5 |
HIP 91998 |
19.73 |
| 2026-10-03 12:00 |
18:45:01.28 |
-21:25:58.4 |
HIP 91998 |
19.42 |
| 2026-10-04 00:00 |
18:44:46.89 |
-21:26:04.9 |
HIP 91998 |
19.70 |
| 2026-10-04 12:00 |
18:44:32.76 |
-21:26:11.1 |
HIP 91998 |
20.52 |
| 2026-10-05 00:00 |
18:44:18.89 |
-21:26:17.0 |
HIP 91998 |
21.78 |
| 2026-10-05 12:00 |
18:44:05.28 |
-21:26:22.5 |
HIP 91998 |
23.39 |
| 2026-10-06 00:00 |
18:43:51.93 |
-21:26:27.7 |
HIP 91998 |
25.25 |
| 2026-10-06 12:00 |
18:43:38.83 |
-21:26:32.6 |
HIP 91998 |
27.31 |
| 2026-10-07 00:00 |
18:43:25.99 |
-21:26:37.2 |
HIP 91998 |
29.49 |
| 2026-10-07 12:00 |
18:43:13.41 |
-21:26:41.5 |
HIP 91998 |
31.76 |
| 2026-10-08 00:00 |
18:43:01.08 |
-21:26:45.4 |
HIP 91849 |
32.47 |
| 2026-10-08 12:00 |
18:42:49.01 |
-21:26:49.1 |
HIP 91849 |
33.28 |
| 2026-10-09 00:00 |
18:42:37.19 |
-21:26:52.5 |
HIP 91849 |
34.28 |
| 2026-10-09 12:00 |
18:42:25.62 |
-21:26:55.5 |
HIP 91849 |
35.43 |
| 2026-10-10 00:00 |
18:42:14.30 |
-21:26:58.3 |
HIP 91849 |
36.72 |
| 2026-10-10 12:00 |
18:42:03.23 |
-21:27:00.8 |
HIP 91849 |
38.10 |
| 2026-10-11 00:00 |
18:41:52.41 |
-21:27:02.9 |
HIP 91849 |
39.57 |
| 2026-10-11 12:00 |
18:41:41.84 |
-21:27:04.8 |
HIP 91849 |
41.10 |
| 2026-10-12 00:00 |
18:41:31.51 |
-21:27:06.5 |
HIP 91487 |
41.76 |
| 2026-10-12 12:00 |
18:41:21.43 |
-21:27:07.8 |
HIP 91487 |
40.20 |
| 2026-10-13 00:00 |
18:41:11.59 |
-21:27:08.9 |
HIP 91487 |
38.76 |
| 2026-10-13 12:00 |
18:41:02.00 |
-21:27:09.7 |
HIP 91487 |
37.43 |
| 2026-10-14 00:00 |
18:40:52.65 |
-21:27:10.2 |
HIP 91487 |
36.23 |
| 2026-10-14 12:00 |
18:40:43.53 |
-21:27:10.4 |
HIP 91487 |
35.16 |
| 2026-10-15 00:00 |
18:40:34.66 |
-21:27:10.4 |
HIP 91438 |
33.71 |
| 2026-10-15 12:00 |
18:40:26.02 |
-21:27:10.2 |
HIP 91438 |
32.33 |
| 2026-10-16 00:00 |
18:40:17.62 |
-21:27:09.6 |
HIP 91438 |
31.05 |