C/2025 O2 (MAPS)
| Parameter |
Value |
| Designation |
C/2025 O2 (MAPS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2025-05-23T16:42:19.152000Z |
| Orbit solution date (soln_date, UTC) |
2025-09-22T13:42:18Z |
| Obs used |
88 |
| NEO |
- |
| M1 |
7.400 |
| K1 |
27.000 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2025-07-25T09:35:29.760000Z |
| Discovery magnitude (MPC) |
18.80 G |
| Discovery observatory (MPC) |
W94 · MAPS, San Pedro de Atacama |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2025-08-14.0000000 |
| e |
0.99886564 |
| q (au) |
2.288532 |
| a (au) |
2017.460252 |
| i (deg) |
134.542008 |
| Ω (om, deg) |
332.313059 |
| ω (w, deg) |
280.240987 |
| M (ma, deg) |
0.000895 |
Magnitude
Scatter + Global Linear
$$
M_a = (11.254 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
11.254 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.504 |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-02-03 00:00 |
22:18:55.84 |
-13:57:32.0 |
HIP 110333 |
27.50 |
| 2026-02-03 12:00 |
22:19:06.36 |
-13:53:29.1 |
HIP 110333 |
25.47 |
| 2026-02-04 00:00 |
22:19:16.91 |
-13:49:26.7 |
HIP 110333 |
24.21 |
| 2026-02-04 12:00 |
22:19:27.49 |
-13:45:24.8 |
HIP 110333 |
23.86 |
| 2026-02-05 00:00 |
22:19:38.10 |
-13:41:23.4 |
HIP 110333 |
24.43 |
| 2026-02-05 12:00 |
22:19:48.74 |
-13:37:22.5 |
HIP 110179 |
22.37 |
| 2026-02-06 00:00 |
22:19:59.40 |
-13:33:22.1 |
HIP 110179 |
20.76 |
| 2026-02-06 12:00 |
22:20:10.09 |
-13:29:22.2 |
HIP 110179 |
20.18 |
| 2026-02-07 00:00 |
22:20:20.80 |
-13:25:22.8 |
HIP 110179 |
20.73 |
| 2026-02-07 12:00 |
22:20:31.53 |
-13:21:23.8 |
HIP 110179 |
22.31 |
| 2026-02-08 00:00 |
22:20:42.28 |
-13:17:25.4 |
HIP 110179 |
24.73 |
| 2026-02-08 12:00 |
22:20:53.05 |
-13:13:27.4 |
HIP 110179 |
27.76 |
| 2026-02-09 00:00 |
22:21:03.84 |
-13:09:29.9 |
HIP 110179 |
31.23 |
| 2026-02-09 12:00 |
22:21:14.65 |
-13:05:32.9 |
HIP 110179 |
35.01 |
| 2026-02-10 00:00 |
22:21:25.47 |
-13:01:36.4 |
HIP 110179 |
38.99 |
| 2026-02-10 12:00 |
22:21:36.30 |
-12:57:40.3 |
HIP 110179 |
43.13 |
| 2026-02-11 00:00 |
22:21:47.14 |
-12:53:44.7 |
HIP 110375 |
43.01 |
| 2026-02-11 12:00 |
22:21:58.00 |
-12:49:49.6 |
HIP 110375 |
39.63 |
| 2026-02-12 00:00 |
22:22:08.87 |
-12:45:54.9 |
HIP 110375 |
36.55 |
| 2026-02-12 12:00 |
22:22:19.74 |
-12:42:00.7 |
HIP 110375 |
33.86 |
| 2026-02-13 00:00 |
22:22:30.62 |
-12:38:07.0 |
HIP 110375 |
31.67 |
| 2026-02-13 12:00 |
22:22:41.51 |
-12:34:13.7 |
HIP 110375 |
30.06 |
| 2026-02-14 00:00 |
22:22:52.40 |
-12:30:20.9 |
HIP 110375 |
29.14 |
| 2026-02-14 12:00 |
22:23:03.29 |
-12:26:28.5 |
HIP 110375 |
28.97 |
| 2026-02-15 00:00 |
22:23:14.18 |
-12:22:36.6 |
HIP 110375 |
29.56 |
| 2026-02-15 12:00 |
22:23:25.08 |
-12:18:45.1 |
HIP 110375 |
30.86 |
| 2026-02-16 00:00 |
22:23:35.97 |
-12:14:54.1 |
HIP 110375 |
32.79 |
| 2026-02-16 12:00 |
22:23:46.86 |
-12:11:03.6 |
HIP 110688 |
30.40 |
| 2026-02-17 00:00 |
22:23:57.74 |
-12:07:13.5 |
HIP 110688 |
26.14 |
| 2026-02-17 12:00 |
22:24:08.62 |
-12:03:23.8 |
HIP 110688 |
22.05 |
| 2026-02-18 00:00 |
22:24:19.49 |
-11:59:34.6 |
HIP 110688 |
18.23 |
| 2026-02-18 12:00 |
22:24:30.36 |
-11:55:45.9 |
HIP 110688 |
14.91 |
| 2026-02-19 00:00 |
22:24:41.21 |
-11:51:57.6 |
HIP 110688 |
12.46 |
| 2026-02-19 12:00 |
22:24:52.05 |
-11:48:09.7 |
HIP 110688 |
11.45 |
| 2026-02-20 00:00 |
22:25:02.88 |
-11:44:22.3 |
HIP 110620 |
11.66 |
| 2026-02-20 12:00 |
22:25:13.70 |
-11:40:35.3 |
HIP 110620 |
10.89 |
| 2026-02-21 00:00 |
22:25:24.50 |
-11:36:48.8 |
HIP 110620 |
12.00 |
| 2026-02-21 12:00 |
22:25:35.28 |
-11:33:02.7 |
HIP 110620 |
14.55 |
| 2026-02-22 00:00 |
22:25:46.05 |
-11:29:17.1 |
HIP 110620 |
17.93 |
| 2026-02-22 12:00 |
22:25:56.80 |
-11:25:31.9 |
HIP 110691 |
15.87 |
| 2026-02-23 00:00 |
22:26:07.52 |
-11:21:47.2 |
HIP 110786 |
11.64 |
| 2026-02-23 12:00 |
22:26:18.23 |
-11:18:02.9 |
HIP 110786 |
7.21 |
| 2026-02-24 00:00 |
22:26:28.91 |
-11:14:19.1 |
HIP 110786 |
3.19 |