| Parameter |
Value |
| Designation |
C/2025 M1 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2029-08-03T14:21:41.872320Z |
| Orbit solution date (soln_date, UTC) |
2026-03-07T14:43:16Z |
| Obs used |
62 |
| NEO |
- |
| M1 |
6.700 |
| K1 |
7.000 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2025-06-21T08:14:47.731200Z |
| Discovery magnitude (MPC) |
20.92 w |
| Discovery observatory (MPC) |
F52 · Pan-STARRS 2, Haleakala |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2024-11-18.0000000 |
| e |
0.99845584 |
| q (au) |
10.825979 |
| a (au) |
7010.915716 |
| i (deg) |
64.906803 |
| Ω (om, deg) |
66.958312 |
| ω (w, deg) |
230.454419 |
| M (ma, deg) |
359.997113 |
Magnitude
Scatter + Global Linear
$$
M_a = (6.209 + 4.947\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
6.209 |
| n |
4.947 |
| gf |
1.000 |
| gb |
-0.873 |
| k |
0.800 |
| δ90 |
9.982 |
| 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 |
16:38:10.82 |
-30:28:11.2 |
HIP 81552 |
15.07 |
| 2026-05-12 12:00 |
16:38:01.25 |
-30:28:54.9 |
HIP 81552 |
17.16 |
| 2026-05-13 00:00 |
16:37:51.64 |
-30:29:38.3 |
HIP 81327 |
16.95 |
| 2026-05-13 12:00 |
16:37:41.98 |
-30:30:21.5 |
HIP 81327 |
14.75 |
| 2026-05-14 00:00 |
16:37:32.28 |
-30:31:04.4 |
HIP 81327 |
12.54 |
| 2026-05-14 12:00 |
16:37:22.54 |
-30:31:47.1 |
HIP 81327 |
10.32 |
| 2026-05-15 00:00 |
16:37:12.76 |
-30:32:29.5 |
HIP 81327 |
8.10 |
| 2026-05-15 12:00 |
16:37:02.94 |
-30:33:11.7 |
HIP 81327 |
5.88 |
| 2026-05-16 00:00 |
16:36:53.09 |
-30:33:53.6 |
HIP 81327 |
3.64 |
| 2026-05-16 12:00 |
16:36:43.19 |
-30:34:35.3 |
HIP 81327 |
1.40 |
| 2026-05-17 00:00 |
16:36:33.26 |
-30:35:16.7 |
HIP 81327 |
0.84 |
| 2026-05-17 12:00 |
16:36:23.30 |
-30:35:57.8 |
HIP 81327 |
3.09 |
| 2026-05-18 00:00 |
16:36:13.31 |
-30:36:38.7 |
HIP 81327 |
5.35 |
| 2026-05-18 12:00 |
16:36:03.28 |
-30:37:19.3 |
HIP 81327 |
7.61 |
| 2026-05-19 00:00 |
16:35:53.22 |
-30:37:59.7 |
HIP 81327 |
9.88 |
| 2026-05-19 12:00 |
16:35:43.13 |
-30:38:39.8 |
HIP 81327 |
12.15 |
| 2026-05-20 00:00 |
16:35:33.01 |
-30:39:19.7 |
HIP 81327 |
14.43 |
| 2026-05-20 12:00 |
16:35:22.86 |
-30:39:59.3 |
HIP 81327 |
16.71 |
| 2026-05-21 00:00 |
16:35:12.68 |
-30:40:38.6 |
HIP 81327 |
18.99 |
| 2026-05-21 12:00 |
16:35:02.48 |
-30:41:17.7 |
HIP 81327 |
21.28 |
| 2026-05-22 00:00 |
16:34:52.26 |
-30:41:56.6 |
HIP 81327 |
23.57 |
| 2026-05-22 12:00 |
16:34:42.01 |
-30:42:35.1 |
HIP 81327 |
25.86 |
| 2026-05-23 00:00 |
16:34:31.74 |
-30:43:13.4 |
HIP 81327 |
28.16 |
| 2026-05-23 12:00 |
16:34:21.44 |
-30:43:51.5 |
HIP 81327 |
30.46 |
| 2026-05-24 00:00 |
16:34:11.13 |
-30:44:29.3 |
HIP 81327 |
32.77 |
| 2026-05-24 12:00 |
16:34:00.79 |
-30:45:06.9 |
HIP 81082 |
32.51 |
| 2026-05-25 00:00 |
16:33:50.44 |
-30:45:44.2 |
HIP 81082 |
31.67 |
| 2026-05-25 12:00 |
16:33:40.07 |
-30:46:21.2 |
HIP 81082 |
30.99 |
| 2026-05-26 00:00 |
16:33:29.68 |
-30:46:58.0 |
HIP 81082 |
30.47 |
| 2026-05-26 12:00 |
16:33:19.28 |
-30:47:34.6 |
HIP 81082 |
30.12 |
| 2026-05-27 00:00 |
16:33:08.86 |
-30:48:10.8 |
HIP 81082 |
29.95 |
| 2026-05-27 12:00 |
16:32:58.43 |
-30:48:46.9 |
HIP 81082 |
29.96 |
| 2026-05-28 00:00 |
16:32:47.98 |
-30:49:22.6 |
HIP 81082 |
30.16 |
| 2026-05-28 12:00 |
16:32:37.53 |
-30:49:58.2 |
HIP 81082 |
30.53 |
| 2026-05-29 00:00 |
16:32:27.06 |
-30:50:33.4 |
HIP 81082 |
31.08 |
| 2026-05-29 12:00 |
16:32:16.59 |
-30:51:08.5 |
HIP 81082 |
31.79 |
| 2026-05-30 00:00 |
16:32:06.10 |
-30:51:43.2 |
HIP 81082 |
32.66 |
| 2026-05-30 12:00 |
16:31:55.61 |
-30:52:17.8 |
HIP 81082 |
33.67 |
| 2026-05-31 00:00 |
16:31:45.11 |
-30:52:52.0 |
HIP 80758 |
31.45 |
| 2026-05-31 12:00 |
16:31:34.61 |
-30:53:26.0 |
HIP 80758 |
29.14 |
| 2026-06-01 00:00 |
16:31:24.10 |
-30:53:59.8 |
HIP 80758 |
26.83 |
| 2026-06-01 12:00 |
16:31:13.59 |
-30:54:33.3 |
HIP 80758 |
24.52 |
| 2026-06-02 00:00 |
16:31:03.08 |
-30:55:06.6 |
HIP 80758 |
22.21 |