| Parameter |
Value |
| Designation |
P/2023 M4 (ATLAS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2022-04-15T03:44:22.856640Z |
| Orbit solution date (soln_date, UTC) |
2024-10-11T15:13:32Z |
| Obs used |
1091 |
| NEO |
- |
| M1 |
6.500 |
| K1 |
11.500 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2023-06-21T01:28:09.321600Z |
| Discovery magnitude (MPC) |
16.82 o |
| Discovery observatory (MPC) |
M22 · ATLAS South Africa, Sutherland |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2023-08-07.0000000 |
| e |
0.27942129 |
| q (au) |
3.929545 |
| a (au) |
5.453318 |
| i (deg) |
7.592560 |
| Ω (om, deg) |
296.296071 |
| ω (w, deg) |
320.696493 |
| M (ma, deg) |
37.060144 |
Magnitude
Scatter + Global Linear
$$
M_a = (5.149 + 5.443\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
5.149 |
| n |
5.443 |
| gf |
0.884 |
| gb |
-0.827 |
| k |
0.997 |
| δ90 |
1.000 |
| 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) |
| 2026-09-20 00:00 |
03:04:25.92 |
+25:42:19.3 |
HIP 14379 |
17.60 |
| 2026-09-20 12:00 |
03:04:19.63 |
+25:42:23.0 |
HIP 14379 |
18.76 |
| 2026-09-21 00:00 |
03:04:13.18 |
+25:42:25.9 |
HIP 14379 |
19.99 |
| 2026-09-21 12:00 |
03:04:06.58 |
+25:42:28.1 |
HIP 14379 |
21.28 |
| 2026-09-22 00:00 |
03:03:59.83 |
+25:42:29.4 |
HIP 14379 |
22.64 |
| 2026-09-22 12:00 |
03:03:52.93 |
+25:42:30.0 |
HIP 14379 |
24.05 |
| 2026-09-23 00:00 |
03:03:45.88 |
+25:42:29.7 |
HIP 14379 |
25.51 |
| 2026-09-23 12:00 |
03:03:38.67 |
+25:42:28.7 |
HIP 14379 |
27.03 |
| 2026-09-24 00:00 |
03:03:31.32 |
+25:42:26.8 |
HIP 14088 |
26.21 |
| 2026-09-24 12:00 |
03:03:23.82 |
+25:42:24.2 |
HIP 14088 |
24.59 |
| 2026-09-25 00:00 |
03:03:16.18 |
+25:42:20.8 |
HIP 14088 |
22.95 |
| 2026-09-25 12:00 |
03:03:08.38 |
+25:42:16.5 |
HIP 14088 |
21.29 |
| 2026-09-26 00:00 |
03:03:00.44 |
+25:42:11.5 |
HIP 14088 |
19.63 |
| 2026-09-26 12:00 |
03:02:52.36 |
+25:42:05.7 |
HIP 14088 |
17.96 |
| 2026-09-27 00:00 |
03:02:44.13 |
+25:41:59.0 |
HIP 14088 |
16.31 |
| 2026-09-27 12:00 |
03:02:35.76 |
+25:41:51.6 |
HIP 14088 |
14.68 |
| 2026-09-28 00:00 |
03:02:27.24 |
+25:41:43.3 |
HIP 14088 |
13.10 |
| 2026-09-28 12:00 |
03:02:18.59 |
+25:41:34.2 |
HIP 14088 |
11.61 |
| 2026-09-29 00:00 |
03:02:09.79 |
+25:41:24.3 |
HIP 14088 |
10.26 |
| 2026-09-29 12:00 |
03:02:00.86 |
+25:41:13.6 |
HIP 14088 |
9.14 |
| 2026-09-30 00:00 |
03:01:51.78 |
+25:41:02.0 |
HIP 14088 |
8.37 |
| 2026-09-30 12:00 |
03:01:42.57 |
+25:40:49.7 |
HIP 14088 |
8.07 |
| 2026-10-01 00:00 |
03:01:33.22 |
+25:40:36.5 |
HIP 14088 |
8.32 |
| 2026-10-01 12:00 |
03:01:23.74 |
+25:40:22.5 |
HIP 14088 |
9.09 |
| 2026-10-02 00:00 |
03:01:14.12 |
+25:40:07.6 |
HIP 14088 |
10.29 |
| 2026-10-02 12:00 |
03:01:04.37 |
+25:39:52.0 |
HIP 14088 |
11.81 |
| 2026-10-03 00:00 |
03:00:54.48 |
+25:39:35.5 |
HIP 14088 |
13.55 |
| 2026-10-03 12:00 |
03:00:44.47 |
+25:39:18.2 |
HIP 14088 |
15.45 |
| 2026-10-04 00:00 |
03:00:34.32 |
+25:39:00.0 |
HIP 14088 |
17.47 |
| 2026-10-04 12:00 |
03:00:24.05 |
+25:38:41.0 |
HIP 13915 |
18.83 |
| 2026-10-05 00:00 |
03:00:13.65 |
+25:38:21.2 |
HIP 13915 |
16.74 |
| 2026-10-05 12:00 |
03:00:03.12 |
+25:38:00.6 |
HIP 13915 |
14.72 |
| 2026-10-06 00:00 |
02:59:52.47 |
+25:37:39.1 |
HIP 13915 |
12.79 |
| 2026-10-06 12:00 |
02:59:41.69 |
+25:37:16.8 |
HIP 13915 |
11.04 |
| 2026-10-07 00:00 |
02:59:30.79 |
+25:36:53.7 |
HIP 13915 |
9.58 |
| 2026-10-07 12:00 |
02:59:19.77 |
+25:36:29.7 |
HIP 13915 |
8.59 |
| 2026-10-08 00:00 |
02:59:08.63 |
+25:36:04.9 |
HIP 13915 |
8.27 |
| 2026-10-08 12:00 |
02:58:57.38 |
+25:35:39.3 |
HIP 13915 |
8.71 |
| 2026-10-09 00:00 |
02:58:46.01 |
+25:35:12.9 |
HIP 13915 |
9.84 |
| 2026-10-09 12:00 |
02:58:34.52 |
+25:34:45.6 |
HIP 13915 |
11.47 |
| 2026-10-10 00:00 |
02:58:22.92 |
+25:34:17.5 |
HIP 13915 |
13.44 |
| 2026-10-10 12:00 |
02:58:11.22 |
+25:33:48.6 |
HIP 13915 |
15.63 |
| 2026-10-11 00:00 |
02:57:59.40 |
+25:33:18.8 |
HIP 13915 |
17.98 |