| Parameter |
Value |
| Designation |
C/2024 J3 (ATLAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2026-11-25T08:27:48.545280Z |
| Orbit solution date (soln_date, UTC) |
2026-05-08T13:42:11Z |
| Obs used |
1389 |
| NEO |
- |
| M1 |
8.500 |
| K1 |
5.750 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2024-05-06T06:21:33.667200Z |
| Discovery magnitude (MPC) |
17.60 o |
| Discovery observatory (MPC) |
W68 · ATLAS Chile, Rio Hurtado |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2025-07-18.0000000 |
| e |
1.00065044 |
| q (au) |
3.865221 |
| a (au) |
-5942.429213 |
| i (deg) |
75.640213 |
| Ω (om, deg) |
285.961283 |
| ω (w, deg) |
74.089525 |
| M (ma, deg) |
-0.001066 |
Magnitude
Scatter + Global Linear
$$
M_a = (5.360 + 3.386\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
5.360 |
| n |
3.386 |
| gf |
0.997 |
| gb |
-0.892 |
| k |
1.000 |
| δ90 |
9.999 |
| 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 |
20:23:15.39 |
+22:48:51.1 |
HIP 100390 |
23.90 |
| 2026-05-12 12:00 |
20:23:11.92 |
+22:57:59.2 |
HIP 100390 |
24.06 |
| 2026-05-13 00:00 |
20:23:08.18 |
+23:07:08.0 |
HIP 100374 |
25.38 |
| 2026-05-13 12:00 |
20:23:04.17 |
+23:16:17.4 |
HIP 100374 |
23.10 |
| 2026-05-14 00:00 |
20:22:59.89 |
+23:25:27.4 |
HIP 100555 |
15.80 |
| 2026-05-14 12:00 |
20:22:55.34 |
+23:34:37.9 |
HIP 100555 |
8.76 |
| 2026-05-15 00:00 |
20:22:50.51 |
+23:43:49.0 |
HIP 100555 |
8.67 |
| 2026-05-15 12:00 |
20:22:45.41 |
+23:53:00.6 |
HIP 100543 |
11.03 |
| 2026-05-16 00:00 |
20:22:40.02 |
+24:02:12.6 |
HIP 100543 |
7.31 |
| 2026-05-16 12:00 |
20:22:34.36 |
+24:11:25.1 |
HIP 100543 |
12.60 |
| 2026-05-17 00:00 |
20:22:28.42 |
+24:20:38.1 |
HIP 100435 |
8.37 |
| 2026-05-17 12:00 |
20:22:22.19 |
+24:29:51.4 |
HIP 100435 |
5.27 |
| 2026-05-18 00:00 |
20:22:15.69 |
+24:39:05.0 |
HIP 100435 |
12.63 |
| 2026-05-18 12:00 |
20:22:08.89 |
+24:48:19.0 |
HIP 100435 |
21.59 |
| 2026-05-19 00:00 |
20:22:01.81 |
+24:57:33.3 |
HIP 100435 |
30.79 |
| 2026-05-19 12:00 |
20:21:54.44 |
+25:06:47.8 |
HIP 100350 |
32.85 |
| 2026-05-20 00:00 |
20:21:46.78 |
+25:16:02.6 |
HIP 100350 |
23.59 |
| 2026-05-20 12:00 |
20:21:38.84 |
+25:25:17.6 |
HIP 100350 |
14.49 |
| 2026-05-21 00:00 |
20:21:30.60 |
+25:34:32.7 |
HIP 100350 |
6.36 |
| 2026-05-21 12:00 |
20:21:22.06 |
+25:43:48.0 |
HIP 100415 |
4.86 |
| 2026-05-22 00:00 |
20:21:13.24 |
+25:53:03.4 |
HIP 100415 |
10.43 |
| 2026-05-22 12:00 |
20:21:04.12 |
+26:02:18.8 |
HIP 100415 |
19.35 |
| 2026-05-23 00:00 |
20:20:54.70 |
+26:11:34.3 |
HIP 100441 |
18.81 |
| 2026-05-23 12:00 |
20:20:44.98 |
+26:20:49.8 |
HIP 100441 |
18.84 |
| 2026-05-24 00:00 |
20:20:34.97 |
+26:30:05.3 |
HIP 100441 |
23.23 |
| 2026-05-24 12:00 |
20:20:24.65 |
+26:39:20.7 |
HIP 100145 |
29.07 |
| 2026-05-25 00:00 |
20:20:14.04 |
+26:48:36.1 |
HIP 100145 |
21.53 |
| 2026-05-25 12:00 |
20:20:03.12 |
+26:57:51.3 |
HIP 100145 |
16.22 |
| 2026-05-26 00:00 |
20:19:51.90 |
+27:07:06.3 |
HIP 100145 |
15.62 |
| 2026-05-26 12:00 |
20:19:40.37 |
+27:16:21.2 |
HIP 100343 |
19.48 |
| 2026-05-27 00:00 |
20:19:28.54 |
+27:25:35.8 |
HIP 100120 |
13.57 |
| 2026-05-27 12:00 |
20:19:16.41 |
+27:34:50.2 |
HIP 100120 |
8.86 |
| 2026-05-28 00:00 |
20:19:03.96 |
+27:44:04.3 |
HIP 100120 |
12.53 |
| 2026-05-28 12:00 |
20:18:51.21 |
+27:53:18.0 |
HIP 100120 |
20.52 |
| 2026-05-29 00:00 |
20:18:38.14 |
+28:02:31.4 |
HIP 100020 |
14.53 |
| 2026-05-29 12:00 |
20:18:24.77 |
+28:11:44.4 |
HIP 100020 |
12.07 |
| 2026-05-30 00:00 |
20:18:11.08 |
+28:20:56.9 |
HIP 100021 |
12.75 |
| 2026-05-30 12:00 |
20:17:57.08 |
+28:30:08.9 |
HIP 100021 |
4.79 |
| 2026-05-31 00:00 |
20:17:42.76 |
+28:39:20.4 |
HIP 100021 |
8.43 |
| 2026-05-31 12:00 |
20:17:28.13 |
+28:48:31.4 |
HIP 99999 |
7.19 |
| 2026-06-01 00:00 |
20:17:13.18 |
+28:57:41.8 |
HIP 99999 |
2.76 |
| 2026-06-01 12:00 |
20:16:57.92 |
+29:06:51.5 |
HIP 99924 |
7.09 |
| 2026-06-02 00:00 |
20:16:42.34 |
+29:16:00.5 |
HIP 99924 |
8.85 |