| Parameter |
Value |
| Designation |
C/2025 N2 (ATLAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2024-12-12T18:30:52.908480Z |
| Orbit solution date (soln_date, UTC) |
2026-07-06T12:12:27Z |
| Obs used |
49 |
| NEO |
- |
| M1 |
6.400 |
| K1 |
8.500 |
| 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) |
2025-07-27.0000000 |
| e |
1.00220626 |
| q (au) |
8.984848 |
| a (au) |
-4072.429280 |
| i (deg) |
81.664420 |
| Ω (om, deg) |
94.462885 |
| ω (w, deg) |
230.115528 |
| M (ma, deg) |
0.000858 |
Magnitude
Scatter + Global Linear
$$
M_a = (-0.838 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
-0.838 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.502 |
| 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) |
| 2026-07-29 00:00 |
04:51:44.45 |
-70:45:57.3 |
HIP 22338 |
21.53 |
| 2026-07-29 12:00 |
04:52:12.71 |
-70:47:07.0 |
HIP 22974 |
21.76 |
| 2026-07-30 00:00 |
04:52:40.76 |
-70:48:17.3 |
HIP 22974 |
19.49 |
| 2026-07-30 12:00 |
04:53:08.62 |
-70:49:28.3 |
HIP 22974 |
17.33 |
| 2026-07-31 00:00 |
04:53:36.27 |
-70:50:40.0 |
HIP 22974 |
15.32 |
| 2026-07-31 12:00 |
04:54:03.73 |
-70:51:52.3 |
HIP 22974 |
13.53 |
| 2026-08-01 00:00 |
04:54:30.98 |
-70:53:05.3 |
HIP 22998 |
11.69 |
| 2026-08-01 12:00 |
04:54:58.03 |
-70:54:18.9 |
HIP 22998 |
9.29 |
| 2026-08-02 00:00 |
04:55:24.87 |
-70:55:33.2 |
HIP 22998 |
7.02 |
| 2026-08-02 12:00 |
04:55:51.50 |
-70:56:48.1 |
HIP 22998 |
5.01 |
| 2026-08-03 00:00 |
04:56:17.92 |
-70:58:03.7 |
HIP 22998 |
3.71 |
| 2026-08-03 12:00 |
04:56:44.14 |
-70:59:19.9 |
HIP 22998 |
3.86 |
| 2026-08-04 00:00 |
04:57:10.14 |
-71:00:36.8 |
HIP 22998 |
5.35 |
| 2026-08-04 12:00 |
04:57:35.93 |
-71:01:54.3 |
HIP 22998 |
7.38 |
| 2026-08-05 00:00 |
04:58:01.51 |
-71:03:12.4 |
HIP 22998 |
9.62 |
| 2026-08-05 12:00 |
04:58:26.86 |
-71:04:31.1 |
HIP 22998 |
11.93 |
| 2026-08-06 00:00 |
04:58:52.01 |
-71:05:50.4 |
HIP 22998 |
14.28 |
| 2026-08-06 12:00 |
04:59:16.93 |
-71:07:10.4 |
HIP 22998 |
16.65 |
| 2026-08-07 00:00 |
04:59:41.63 |
-71:08:31.0 |
HIP 23428 |
16.56 |
| 2026-08-07 12:00 |
05:00:06.10 |
-71:09:52.2 |
HIP 23428 |
14.22 |
| 2026-08-08 00:00 |
05:00:30.36 |
-71:11:13.9 |
HIP 23428 |
11.89 |
| 2026-08-08 12:00 |
05:00:54.38 |
-71:12:36.3 |
HIP 23428 |
9.61 |
| 2026-08-09 00:00 |
05:01:18.18 |
-71:13:59.2 |
HIP 23428 |
7.38 |
| 2026-08-09 12:00 |
05:01:41.75 |
-71:15:22.8 |
HIP 23428 |
5.26 |
| 2026-08-10 00:00 |
05:02:05.08 |
-71:16:46.9 |
HIP 23428 |
3.44 |
| 2026-08-10 12:00 |
05:02:28.19 |
-71:18:11.6 |
HIP 23467 |
1.36 |
| 2026-08-11 00:00 |
05:02:51.06 |
-71:19:36.8 |
HIP 23467 |
0.99 |
| 2026-08-11 12:00 |
05:03:13.69 |
-71:21:02.6 |
HIP 23467 |
3.29 |
| 2026-08-12 00:00 |
05:03:36.08 |
-71:22:29.0 |
HIP 23467 |
5.58 |
| 2026-08-12 12:00 |
05:03:58.23 |
-71:23:55.9 |
HIP 23467 |
7.87 |
| 2026-08-13 00:00 |
05:04:20.14 |
-71:25:23.3 |
HIP 23467 |
10.14 |
| 2026-08-13 12:00 |
05:04:41.80 |
-71:26:51.2 |
HIP 23467 |
12.40 |
| 2026-08-14 00:00 |
05:05:03.22 |
-71:28:19.7 |
HIP 23467 |
14.65 |
| 2026-08-14 12:00 |
05:05:24.39 |
-71:29:48.7 |
HIP 23467 |
16.90 |
| 2026-08-15 00:00 |
05:05:45.31 |
-71:31:18.2 |
HIP 23467 |
19.12 |
| 2026-08-15 12:00 |
05:06:05.98 |
-71:32:48.2 |
HIP 24006 |
19.05 |
| 2026-08-16 00:00 |
05:06:26.40 |
-71:34:18.6 |
HIP 24006 |
18.41 |
| 2026-08-16 12:00 |
05:06:46.57 |
-71:35:49.6 |
HIP 24006 |
18.05 |
| 2026-08-17 00:00 |
05:07:06.48 |
-71:37:21.0 |
HIP 24006 |
17.98 |
| 2026-08-17 12:00 |
05:07:26.13 |
-71:38:52.9 |
HIP 24006 |
18.19 |
| 2026-08-18 00:00 |
05:07:45.53 |
-71:40:25.2 |
HIP 24006 |
18.68 |
| 2026-08-18 12:00 |
05:08:04.66 |
-71:41:58.0 |
HIP 24006 |
19.42 |
| 2026-08-19 00:00 |
05:08:23.53 |
-71:43:31.3 |
HIP 24006 |
20.38 |