| 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) |
| 2026-07-29 00:00 |
01:21:13.23 |
+62:22:33.5 |
HIP 6174 |
14.29 |
| 2026-07-29 12:00 |
01:20:57.02 |
+62:25:23.9 |
HIP 6174 |
12.45 |
| 2026-07-30 00:00 |
01:20:40.51 |
+62:28:13.5 |
HIP 6174 |
11.33 |
| 2026-07-30 12:00 |
01:20:23.69 |
+62:31:02.4 |
HIP 6174 |
11.14 |
| 2026-07-31 00:00 |
01:20:06.58 |
+62:33:50.4 |
HIP 6174 |
11.95 |
| 2026-07-31 12:00 |
01:19:49.16 |
+62:36:37.5 |
HIP 6174 |
13.58 |
| 2026-08-01 00:00 |
01:19:31.44 |
+62:39:23.8 |
HIP 6174 |
15.78 |
| 2026-08-01 12:00 |
01:19:13.42 |
+62:42:09.3 |
HIP 6174 |
18.35 |
| 2026-08-02 00:00 |
01:18:55.08 |
+62:44:53.8 |
HIP 6174 |
21.16 |
| 2026-08-02 12:00 |
01:18:36.45 |
+62:47:37.5 |
HIP 6174 |
24.14 |
| 2026-08-03 00:00 |
01:18:17.50 |
+62:50:20.2 |
HIP 5839 |
25.27 |
| 2026-08-03 12:00 |
01:17:58.25 |
+62:53:02.0 |
HIP 5839 |
24.46 |
| 2026-08-04 00:00 |
01:17:38.69 |
+62:55:42.8 |
HIP 5839 |
24.09 |
| 2026-08-04 12:00 |
01:17:18.82 |
+62:58:22.6 |
HIP 5839 |
24.19 |
| 2026-08-05 00:00 |
01:16:58.64 |
+63:01:01.5 |
HIP 5839 |
24.77 |
| 2026-08-05 12:00 |
01:16:38.16 |
+63:03:39.3 |
HIP 5839 |
25.78 |
| 2026-08-06 00:00 |
01:16:17.36 |
+63:06:16.1 |
HIP 5696 |
26.28 |
| 2026-08-06 12:00 |
01:15:56.25 |
+63:08:51.8 |
HIP 5696 |
26.28 |
| 2026-08-07 00:00 |
01:15:34.83 |
+63:11:26.4 |
HIP 5696 |
26.71 |
| 2026-08-07 12:00 |
01:15:13.09 |
+63:14:00.0 |
HIP 5696 |
27.57 |
| 2026-08-08 00:00 |
01:14:51.05 |
+63:16:32.4 |
HIP 6105 |
28.69 |
| 2026-08-08 12:00 |
01:14:28.69 |
+63:19:03.7 |
HIP 6105 |
29.53 |
| 2026-08-09 00:00 |
01:14:06.03 |
+63:21:33.8 |
HIP 6105 |
30.79 |
| 2026-08-09 12:00 |
01:13:43.04 |
+63:24:02.8 |
HIP 6105 |
32.42 |
| 2026-08-10 00:00 |
01:13:19.75 |
+63:26:30.5 |
HIP 5693 |
30.28 |
| 2026-08-10 12:00 |
01:12:56.15 |
+63:28:57.0 |
HIP 5693 |
27.91 |
| 2026-08-11 00:00 |
01:12:32.23 |
+63:31:22.3 |
HIP 5693 |
25.84 |
| 2026-08-11 12:00 |
01:12:08.00 |
+63:33:46.3 |
HIP 5693 |
24.17 |
| 2026-08-12 00:00 |
01:11:43.46 |
+63:36:09.1 |
HIP 5353 |
22.61 |
| 2026-08-12 12:00 |
01:11:18.61 |
+63:38:30.5 |
HIP 5353 |
20.65 |
| 2026-08-13 00:00 |
01:10:53.45 |
+63:40:50.6 |
HIP 5353 |
19.16 |
| 2026-08-13 12:00 |
01:10:27.98 |
+63:43:09.3 |
HIP 5353 |
18.25 |
| 2026-08-14 00:00 |
01:10:02.20 |
+63:45:26.7 |
HIP 5353 |
18.01 |
| 2026-08-14 12:00 |
01:09:36.11 |
+63:47:42.7 |
HIP 5239 |
17.32 |
| 2026-08-15 00:00 |
01:09:09.71 |
+63:49:57.2 |
HIP 5239 |
14.78 |
| 2026-08-15 12:00 |
01:08:43.01 |
+63:52:10.4 |
HIP 5247 |
11.47 |
| 2026-08-16 00:00 |
01:08:16.01 |
+63:54:22.1 |
HIP 5247 |
7.95 |
| 2026-08-16 12:00 |
01:07:48.70 |
+63:56:32.3 |
HIP 5247 |
4.67 |
| 2026-08-17 00:00 |
01:07:21.09 |
+63:58:41.0 |
HIP 5247 |
2.78 |
| 2026-08-17 12:00 |
01:06:53.17 |
+64:00:48.2 |
HIP 5247 |
4.60 |
| 2026-08-18 00:00 |
01:06:24.96 |
+64:02:53.9 |
HIP 5247 |
7.89 |
| 2026-08-18 12:00 |
01:05:56.45 |
+64:04:58.0 |
HIP 5247 |
11.45 |
| 2026-08-19 00:00 |
01:05:27.64 |
+64:07:00.6 |
HIP 5247 |
15.11 |