| Parameter |
Value |
| Designation |
C/2024 A2 (ATLAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2024-04-28T21:48:07.764480Z |
| Orbit solution date (soln_date, UTC) |
2025-02-13T09:12:46Z |
| Obs used |
497 |
| NEO |
- |
| M1 |
14.600 |
| K1 |
4.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2024-01-15T08:03:10.915200Z |
| Discovery magnitude (MPC) |
18.04 o |
| Discovery observatory (MPC) |
W68 · ATLAS Chile, Rio Hurtado |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2024-07-05.0000000 |
| e |
0.94184736 |
| q (au) |
1.881640 |
| a (au) |
32.356907 |
| i (deg) |
119.111392 |
| Ω (om, deg) |
78.167124 |
| ω (w, deg) |
295.581197 |
| M (ma, deg) |
0.359271 |
Magnitude
Scatter + Global Linear
$$
M_a = (13.792 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
13.792 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.726 |
| k |
0.995 |
| 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
Finding Chart
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
01:17:01.91 |
+54:38:45.9 |
HIP 6045 |
19.38 |
| 2026-05-12 12:00 |
01:17:15.17 |
+54:41:14.5 |
HIP 6045 |
16.53 |
| 2026-05-13 00:00 |
01:17:28.34 |
+54:43:43.8 |
HIP 6045 |
13.79 |
| 2026-05-13 12:00 |
01:17:41.43 |
+54:46:13.9 |
HIP 6045 |
11.24 |
| 2026-05-14 00:00 |
01:17:54.44 |
+54:48:44.6 |
HIP 6045 |
9.04 |
| 2026-05-14 12:00 |
01:18:07.36 |
+54:51:16.1 |
HIP 6045 |
7.52 |
| 2026-05-15 00:00 |
01:18:20.19 |
+54:53:48.4 |
HIP 6045 |
7.13 |
| 2026-05-15 12:00 |
01:18:32.94 |
+54:56:21.3 |
HIP 6045 |
8.03 |
| 2026-05-16 00:00 |
01:18:45.60 |
+54:58:55.0 |
HIP 6045 |
9.87 |
| 2026-05-16 12:00 |
01:18:58.16 |
+55:01:29.4 |
HIP 6045 |
12.24 |
| 2026-05-17 00:00 |
01:19:10.64 |
+55:04:04.4 |
HIP 6285 |
13.90 |
| 2026-05-17 12:00 |
01:19:23.02 |
+55:06:40.2 |
HIP 6285 |
13.85 |
| 2026-05-18 00:00 |
01:19:35.30 |
+55:09:16.6 |
HIP 6285 |
14.52 |
| 2026-05-18 12:00 |
01:19:47.49 |
+55:11:53.7 |
HIP 6285 |
15.82 |
| 2026-05-19 00:00 |
01:19:59.59 |
+55:14:31.5 |
HIP 6285 |
17.61 |
| 2026-05-19 12:00 |
01:20:11.58 |
+55:17:10.0 |
HIP 6153 |
19.37 |
| 2026-05-20 00:00 |
01:20:23.48 |
+55:19:49.1 |
HIP 6153 |
18.29 |
| 2026-05-20 12:00 |
01:20:35.27 |
+55:22:28.8 |
HIP 6153 |
17.69 |
| 2026-05-21 00:00 |
01:20:46.97 |
+55:25:09.2 |
HIP 6153 |
17.61 |
| 2026-05-21 12:00 |
01:20:58.56 |
+55:27:50.3 |
HIP 6153 |
18.07 |
| 2026-05-22 00:00 |
01:21:10.04 |
+55:30:31.9 |
HIP 6473 |
18.57 |
| 2026-05-22 12:00 |
01:21:21.42 |
+55:33:14.2 |
HIP 6473 |
16.36 |
| 2026-05-23 00:00 |
01:21:32.70 |
+55:35:57.1 |
HIP 6473 |
14.52 |
| 2026-05-23 12:00 |
01:21:43.86 |
+55:38:40.6 |
HIP 6473 |
13.20 |
| 2026-05-24 00:00 |
01:21:54.92 |
+55:41:24.8 |
HIP 6473 |
12.57 |
| 2026-05-24 12:00 |
01:22:05.87 |
+55:44:09.5 |
HIP 6473 |
12.74 |
| 2026-05-25 00:00 |
01:22:16.70 |
+55:46:54.8 |
HIP 6473 |
13.67 |
| 2026-05-25 12:00 |
01:22:27.43 |
+55:49:40.7 |
HIP 6473 |
15.23 |
| 2026-05-26 00:00 |
01:22:38.04 |
+55:52:27.2 |
HIP 6473 |
17.24 |
| 2026-05-26 12:00 |
01:22:48.53 |
+55:55:14.2 |
HIP 6473 |
19.57 |
| 2026-05-27 00:00 |
01:22:58.92 |
+55:58:01.8 |
HIP 6600 |
20.48 |
| 2026-05-27 12:00 |
01:23:09.18 |
+56:00:50.0 |
HIP 6600 |
17.55 |
| 2026-05-28 00:00 |
01:23:19.33 |
+56:03:38.7 |
HIP 6600 |
14.71 |
| 2026-05-28 12:00 |
01:23:29.35 |
+56:06:28.0 |
HIP 6600 |
12.05 |
| 2026-05-29 00:00 |
01:23:39.26 |
+56:09:17.9 |
HIP 6600 |
9.69 |
| 2026-05-29 12:00 |
01:23:49.04 |
+56:12:08.2 |
HIP 6600 |
7.94 |
| 2026-05-30 00:00 |
01:23:58.71 |
+56:14:59.1 |
HIP 6600 |
7.22 |
| 2026-05-30 12:00 |
01:24:08.24 |
+56:17:50.6 |
HIP 6600 |
7.84 |
| 2026-05-31 00:00 |
01:24:17.66 |
+56:20:42.5 |
HIP 6600 |
9.54 |
| 2026-05-31 12:00 |
01:24:26.95 |
+56:23:35.0 |
HIP 6600 |
11.86 |
| 2026-06-01 00:00 |
01:24:36.11 |
+56:26:28.0 |
HIP 6600 |
14.51 |
| 2026-06-01 12:00 |
01:24:45.14 |
+56:29:21.5 |
HIP 6600 |
17.33 |
| 2026-06-02 00:00 |
01:24:54.04 |
+56:32:15.5 |
HIP 6435 |
19.05 |