| Parameter |
Value |
| Designation |
C/2025 N2 (ATLAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2024-12-11T00:44:51.385920Z |
| Orbit solution date (soln_date, UTC) |
2025-12-18T15:12:23Z |
| Obs used |
47 |
| NEO |
- |
| M1 |
4.900 |
| K1 |
10.000 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2025-07-02T01:33:05.932800Z |
| Discovery magnitude (MPC) |
19.61 c |
| Discovery observatory (MPC) |
M22 · ATLAS South Africa, Sutherland |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2025-08-26.0000000 |
| e |
1.00252212 |
| q (au) |
8.983070 |
| a (au) |
-3561.711006 |
| i (deg) |
81.665566 |
| Ω (om, deg) |
94.465158 |
| ω (w, deg) |
230.022476 |
| M (ma, deg) |
0.001196 |
Magnitude
Scatter + Global Linear
$$
M_a = (10.205 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
10.205 |
| n |
2.000 |
| gf |
0.811 |
| gb |
-0.569 |
| k |
0.892 |
| δ90 |
1.000 |
| 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) |
| 2026-05-12 00:00 |
03:08:54.32 |
-70:27:49.5 |
HIP 14218 |
27.84 |
| 2026-05-12 12:00 |
03:09:41.78 |
-70:26:51.9 |
HIP 15155 |
29.94 |
| 2026-05-13 00:00 |
03:10:29.17 |
-70:25:55.1 |
HIP 15155 |
25.87 |
| 2026-05-13 12:00 |
03:11:16.49 |
-70:24:59.1 |
HIP 15155 |
21.81 |
| 2026-05-14 00:00 |
03:12:03.74 |
-70:24:03.9 |
HIP 15155 |
17.77 |
| 2026-05-14 12:00 |
03:12:50.92 |
-70:23:09.5 |
HIP 15155 |
13.76 |
| 2026-05-15 00:00 |
03:13:38.03 |
-70:22:16.0 |
HIP 15155 |
9.80 |
| 2026-05-15 12:00 |
03:14:25.06 |
-70:21:23.2 |
HIP 15155 |
5.98 |
| 2026-05-16 00:00 |
03:15:12.02 |
-70:20:31.3 |
HIP 15155 |
2.89 |
| 2026-05-16 12:00 |
03:15:58.91 |
-70:19:40.1 |
HIP 15155 |
3.71 |
| 2026-05-17 00:00 |
03:16:45.72 |
-70:18:49.8 |
HIP 15155 |
7.20 |
| 2026-05-17 12:00 |
03:17:32.46 |
-70:18:00.3 |
HIP 15340 |
10.92 |
| 2026-05-18 00:00 |
03:18:19.12 |
-70:17:11.7 |
HIP 15340 |
11.91 |
| 2026-05-18 12:00 |
03:19:05.71 |
-70:16:23.8 |
HIP 15340 |
14.00 |
| 2026-05-19 00:00 |
03:19:52.22 |
-70:15:36.8 |
HIP 15340 |
16.77 |
| 2026-05-19 12:00 |
03:20:38.65 |
-70:14:50.6 |
HIP 15340 |
19.95 |
| 2026-05-20 00:00 |
03:21:25.00 |
-70:14:05.3 |
HIP 15340 |
23.37 |
| 2026-05-20 12:00 |
03:22:11.27 |
-70:13:20.7 |
HIP 15340 |
26.92 |
| 2026-05-21 00:00 |
03:22:57.46 |
-70:12:37.0 |
HIP 15340 |
30.57 |
| 2026-05-21 12:00 |
03:23:43.57 |
-70:11:54.1 |
HIP 15340 |
34.27 |
| 2026-05-22 00:00 |
03:24:29.60 |
-70:11:12.1 |
HIP 15840 |
33.80 |
| 2026-05-22 12:00 |
03:25:15.55 |
-70:10:30.8 |
HIP 15840 |
33.63 |
| 2026-05-23 00:00 |
03:26:01.42 |
-70:09:50.4 |
HIP 16395 |
31.77 |
| 2026-05-23 12:00 |
03:26:47.20 |
-70:09:10.9 |
HIP 16395 |
29.17 |
| 2026-05-24 00:00 |
03:27:32.90 |
-70:08:32.1 |
HIP 16395 |
26.87 |
| 2026-05-24 12:00 |
03:28:18.52 |
-70:07:54.2 |
HIP 16395 |
24.97 |
| 2026-05-25 00:00 |
03:29:04.05 |
-70:07:17.1 |
HIP 16395 |
23.55 |
| 2026-05-25 12:00 |
03:29:49.50 |
-70:06:40.9 |
HIP 16564 |
22.69 |
| 2026-05-26 00:00 |
03:30:34.86 |
-70:06:05.4 |
HIP 16564 |
19.44 |
| 2026-05-26 12:00 |
03:31:20.14 |
-70:05:30.8 |
HIP 16564 |
16.49 |
| 2026-05-27 00:00 |
03:32:05.33 |
-70:04:57.1 |
HIP 16564 |
14.03 |
| 2026-05-27 12:00 |
03:32:50.44 |
-70:04:24.1 |
HIP 16564 |
12.36 |
| 2026-05-28 00:00 |
03:33:35.46 |
-70:03:52.0 |
HIP 16564 |
11.81 |
| 2026-05-28 12:00 |
03:34:20.39 |
-70:03:20.8 |
HIP 16564 |
12.52 |
| 2026-05-29 00:00 |
03:35:05.23 |
-70:02:50.3 |
HIP 16564 |
14.29 |
| 2026-05-29 12:00 |
03:35:49.99 |
-70:02:20.7 |
HIP 16564 |
16.79 |
| 2026-05-30 00:00 |
03:36:34.66 |
-70:01:52.0 |
HIP 16564 |
19.74 |
| 2026-05-30 12:00 |
03:37:19.24 |
-70:01:24.1 |
HIP 16564 |
22.96 |
| 2026-05-31 00:00 |
03:38:03.73 |
-70:00:57.0 |
HIP 16564 |
26.35 |
| 2026-05-31 12:00 |
03:38:48.13 |
-70:00:30.7 |
HIP 16564 |
29.85 |
| 2026-06-01 00:00 |
03:39:32.44 |
-70:00:05.3 |
HIP 17486 |
26.91 |
| 2026-06-01 12:00 |
03:40:16.66 |
-69:59:40.7 |
HIP 17486 |
23.17 |
| 2026-06-02 00:00 |
03:41:00.79 |
-69:59:17.0 |
HIP 17486 |
19.46 |