| Parameter |
Value |
| Designation |
P/2025 C1 (ATLAS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2025-02-06T12:52:50.154240Z |
| Orbit solution date (soln_date, UTC) |
2025-09-30T13:39:40Z |
| Obs used |
385 |
| NEO |
- |
| M1 |
6.900 |
| K1 |
20.250 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2025-02-02T15:11:23.596800Z |
| Discovery magnitude (MPC) |
18.47 c |
| Discovery observatory (MPC) |
T05 · ATLAS-HKO, Haleakala |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2025-02-27.0000000 |
| e |
0.34537178 |
| q (au) |
2.746051 |
| a (au) |
4.194826 |
| i (deg) |
7.517505 |
| Ω (om, deg) |
9.104185 |
| ω (w, deg) |
186.793260 |
| M (ma, deg) |
2.347518 |
Magnitude
Scatter + Global Linear
$$
M_a = (8.324 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
8.324 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.997 |
| 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) |
| 2026-06-01 00:00 |
20:29:39.72 |
-28:19:05.1 |
HIP 101242 |
22.39 |
| 2026-06-01 12:00 |
20:29:34.84 |
-28:20:13.9 |
HIP 100935 |
22.40 |
| 2026-06-02 00:00 |
20:29:29.66 |
-28:21:23.3 |
HIP 100935 |
21.57 |
| 2026-06-02 12:00 |
20:29:24.19 |
-28:22:33.4 |
HIP 100935 |
20.76 |
| 2026-06-03 00:00 |
20:29:18.43 |
-28:23:44.1 |
HIP 100935 |
20.02 |
| 2026-06-03 12:00 |
20:29:12.37 |
-28:24:55.4 |
HIP 100935 |
19.34 |
| 2026-06-04 00:00 |
20:29:06.02 |
-28:26:07.3 |
HIP 100935 |
18.77 |
| 2026-06-04 12:00 |
20:28:59.37 |
-28:27:19.7 |
HIP 100935 |
18.31 |
| 2026-06-05 00:00 |
20:28:52.43 |
-28:28:32.8 |
HIP 100935 |
18.01 |
| 2026-06-05 12:00 |
20:28:45.20 |
-28:29:46.3 |
HIP 100893 |
17.40 |
| 2026-06-06 00:00 |
20:28:37.68 |
-28:31:00.4 |
HIP 100893 |
15.79 |
| 2026-06-06 12:00 |
20:28:29.87 |
-28:32:15.1 |
HIP 100893 |
14.22 |
| 2026-06-07 00:00 |
20:28:21.77 |
-28:33:30.2 |
HIP 100893 |
12.76 |
| 2026-06-07 12:00 |
20:28:13.38 |
-28:34:45.9 |
HIP 100893 |
11.47 |
| 2026-06-08 00:00 |
20:28:04.70 |
-28:36:02.0 |
HIP 100893 |
10.46 |
| 2026-06-08 12:00 |
20:27:55.74 |
-28:37:18.6 |
HIP 100893 |
9.85 |
| 2026-06-09 00:00 |
20:27:46.49 |
-28:38:35.6 |
HIP 100893 |
9.75 |
| 2026-06-09 12:00 |
20:27:36.96 |
-28:39:53.1 |
HIP 100897 |
9.15 |
| 2026-06-10 00:00 |
20:27:27.14 |
-28:41:10.9 |
HIP 100897 |
7.67 |
| 2026-06-10 12:00 |
20:27:17.04 |
-28:42:29.2 |
HIP 100897 |
6.84 |
| 2026-06-11 00:00 |
20:27:06.65 |
-28:43:47.8 |
HIP 100897 |
6.96 |
| 2026-06-11 12:00 |
20:26:55.99 |
-28:45:06.8 |
HIP 100897 |
8.05 |
| 2026-06-12 00:00 |
20:26:45.05 |
-28:46:26.2 |
HIP 100897 |
9.83 |
| 2026-06-12 12:00 |
20:26:33.84 |
-28:47:45.9 |
HIP 100897 |
12.03 |
| 2026-06-13 00:00 |
20:26:22.35 |
-28:49:05.9 |
HIP 100897 |
14.50 |
| 2026-06-13 12:00 |
20:26:10.58 |
-28:50:26.1 |
HIP 100738 |
14.32 |
| 2026-06-14 00:00 |
20:25:58.54 |
-28:51:46.7 |
HIP 100738 |
13.85 |
| 2026-06-14 12:00 |
20:25:46.24 |
-28:53:07.4 |
HIP 100738 |
13.99 |
| 2026-06-15 00:00 |
20:25:33.67 |
-28:54:28.4 |
HIP 100738 |
14.75 |
| 2026-06-15 12:00 |
20:25:20.83 |
-28:55:49.7 |
HIP 100674 |
12.15 |
| 2026-06-16 00:00 |
20:25:07.73 |
-28:57:11.0 |
HIP 100674 |
9.27 |
| 2026-06-16 12:00 |
20:24:54.37 |
-28:58:32.6 |
HIP 100674 |
6.63 |
| 2026-06-17 00:00 |
20:24:40.75 |
-28:59:54.3 |
HIP 100674 |
4.78 |
| 2026-06-17 12:00 |
20:24:26.87 |
-29:01:16.1 |
HIP 100674 |
4.84 |
| 2026-06-18 00:00 |
20:24:12.74 |
-29:02:38.0 |
HIP 100674 |
6.85 |
| 2026-06-18 12:00 |
20:23:58.36 |
-29:04:00.0 |
HIP 100674 |
9.71 |
| 2026-06-19 00:00 |
20:23:43.74 |
-29:05:22.0 |
HIP 100517 |
10.96 |
| 2026-06-19 12:00 |
20:23:28.87 |
-29:06:44.1 |
HIP 100517 |
7.44 |
| 2026-06-20 00:00 |
20:23:13.75 |
-29:08:06.1 |
HIP 100517 |
3.88 |
| 2026-06-20 12:00 |
20:22:58.40 |
-29:09:28.2 |
HIP 100517 |
0.52 |
| 2026-06-21 00:00 |
20:22:42.81 |
-29:10:50.2 |
HIP 100517 |
3.46 |
| 2026-06-21 12:00 |
20:22:26.99 |
-29:12:12.2 |
HIP 100517 |
7.16 |
| 2026-06-22 00:00 |
20:22:10.94 |
-29:13:34.1 |
HIP 100517 |
10.91 |