| Parameter |
Value |
| Designation |
C/2024 G2 (ATLAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2025-06-13T13:01:11.939520Z |
| Orbit solution date (soln_date, UTC) |
2026-05-05T09:12:14Z |
| Obs used |
662 |
| NEO |
- |
| M1 |
4.800 |
| K1 |
13.500 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2024-04-08T07:54:38.131200Z |
| Discovery magnitude (MPC) |
18.63 o |
| Discovery observatory (MPC) |
W68 · ATLAS Chile, Rio Hurtado |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2025-08-10.0000000 |
| e |
0.99265570 |
| q (au) |
5.348245 |
| a (au) |
728.217379 |
| i (deg) |
122.124147 |
| Ω (om, deg) |
171.397562 |
| ω (w, deg) |
328.738909 |
| M (ma, deg) |
0.002882 |
Magnitude
Scatter + Global Linear
$$
M_a = (4.676 + 4.906\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
4.676 |
| n |
4.906 |
| gf |
1.000 |
| gb |
-0.709 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2024-04-08 |
2025-06-12 |
-1.5285 |
+0.884 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
10:51:30.95 |
+11:00:48.2 |
HIP 53115 |
21.76 |
| 2026-05-12 12:00 |
10:51:22.19 |
+11:04:04.9 |
HIP 53115 |
19.58 |
| 2026-05-13 00:00 |
10:51:13.61 |
+11:07:19.8 |
HIP 53115 |
17.99 |
| 2026-05-13 12:00 |
10:51:05.22 |
+11:10:33.0 |
HIP 53115 |
17.13 |
| 2026-05-14 00:00 |
10:50:57.02 |
+11:13:44.5 |
HIP 53115 |
17.07 |
| 2026-05-14 12:00 |
10:50:49.00 |
+11:16:54.2 |
HIP 53115 |
17.78 |
| 2026-05-15 00:00 |
10:50:41.18 |
+11:20:02.1 |
HIP 53039 |
16.15 |
| 2026-05-15 12:00 |
10:50:33.54 |
+11:23:08.4 |
HIP 53039 |
14.42 |
| 2026-05-16 00:00 |
10:50:26.09 |
+11:26:12.9 |
HIP 53039 |
13.45 |
| 2026-05-16 12:00 |
10:50:18.82 |
+11:29:15.7 |
HIP 53039 |
13.35 |
| 2026-05-17 00:00 |
10:50:11.75 |
+11:32:16.8 |
HIP 53039 |
14.13 |
| 2026-05-17 12:00 |
10:50:04.85 |
+11:35:16.2 |
HIP 53039 |
15.61 |
| 2026-05-18 00:00 |
10:49:58.15 |
+11:38:13.9 |
HIP 53039 |
17.59 |
| 2026-05-18 12:00 |
10:49:51.62 |
+11:41:09.9 |
HIP 53039 |
19.91 |
| 2026-05-19 00:00 |
10:49:45.28 |
+11:44:04.2 |
HIP 53039 |
22.43 |
| 2026-05-19 12:00 |
10:49:39.13 |
+11:46:56.9 |
HIP 52833 |
22.41 |
| 2026-05-20 00:00 |
10:49:33.16 |
+11:49:47.9 |
HIP 52833 |
20.31 |
| 2026-05-20 12:00 |
10:49:27.37 |
+11:52:37.3 |
HIP 52833 |
18.57 |
| 2026-05-21 00:00 |
10:49:21.76 |
+11:55:25.0 |
HIP 52833 |
17.28 |
| 2026-05-21 12:00 |
10:49:16.34 |
+11:58:11.2 |
HIP 52833 |
16.52 |
| 2026-05-22 00:00 |
10:49:11.09 |
+12:00:55.6 |
HIP 52833 |
16.34 |
| 2026-05-22 12:00 |
10:49:06.02 |
+12:03:38.5 |
HIP 52833 |
16.73 |
| 2026-05-23 00:00 |
10:49:01.14 |
+12:06:19.8 |
HIP 52833 |
17.64 |
| 2026-05-23 12:00 |
10:48:56.43 |
+12:08:59.5 |
HIP 52833 |
18.97 |
| 2026-05-24 00:00 |
10:48:51.89 |
+12:11:37.6 |
HIP 52833 |
20.62 |
| 2026-05-24 12:00 |
10:48:47.54 |
+12:14:14.1 |
HIP 52833 |
22.51 |
| 2026-05-25 00:00 |
10:48:43.36 |
+12:16:49.1 |
HIP 52833 |
24.56 |
| 2026-05-25 12:00 |
10:48:39.35 |
+12:19:22.5 |
HIP 52833 |
26.74 |
| 2026-05-26 00:00 |
10:48:35.52 |
+12:21:54.3 |
HIP 52833 |
28.99 |
| 2026-05-26 12:00 |
10:48:31.87 |
+12:24:24.7 |
HIP 52915 |
28.65 |
| 2026-05-27 00:00 |
10:48:28.38 |
+12:26:53.5 |
HIP 52915 |
26.79 |
| 2026-05-27 12:00 |
10:48:25.07 |
+12:29:20.8 |
HIP 52915 |
25.07 |
| 2026-05-28 00:00 |
10:48:21.93 |
+12:31:46.6 |
HIP 52915 |
23.50 |
| 2026-05-28 12:00 |
10:48:18.95 |
+12:34:10.9 |
HIP 52915 |
22.10 |
| 2026-05-29 00:00 |
10:48:16.15 |
+12:36:33.7 |
HIP 52915 |
20.90 |
| 2026-05-29 12:00 |
10:48:13.52 |
+12:38:55.1 |
HIP 52915 |
19.92 |
| 2026-05-30 00:00 |
10:48:11.05 |
+12:41:14.9 |
HIP 52915 |
19.17 |
| 2026-05-30 12:00 |
10:48:08.75 |
+12:43:33.4 |
HIP 52915 |
18.68 |
| 2026-05-31 00:00 |
10:48:06.62 |
+12:45:50.4 |
HIP 52915 |
18.45 |
| 2026-05-31 12:00 |
10:48:04.65 |
+12:48:05.9 |
HIP 52915 |
18.48 |
| 2026-06-01 00:00 |
10:48:02.85 |
+12:50:20.0 |
HIP 52915 |
18.75 |
| 2026-06-01 12:00 |
10:48:01.21 |
+12:52:32.8 |
HIP 52746 |
17.46 |
| 2026-06-02 00:00 |
10:47:59.73 |
+12:54:44.1 |
HIP 52746 |
16.02 |