| 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) |
| 2026-07-29 00:00 |
03:00:34.85 |
+24:32:36.7 |
HIP 13867 |
36.57 |
| 2026-07-29 12:00 |
03:00:44.80 |
+24:33:44.9 |
HIP 14080 |
35.24 |
| 2026-07-30 00:00 |
03:00:54.62 |
+24:34:52.7 |
HIP 14080 |
33.58 |
| 2026-07-30 12:00 |
03:01:04.32 |
+24:36:00.1 |
HIP 14080 |
32.05 |
| 2026-07-31 00:00 |
03:01:13.88 |
+24:37:07.0 |
HIP 14080 |
30.64 |
| 2026-07-31 12:00 |
03:01:23.32 |
+24:38:13.5 |
HIP 14080 |
29.39 |
| 2026-08-01 00:00 |
03:01:32.62 |
+24:39:19.5 |
HIP 14080 |
28.29 |
| 2026-08-01 12:00 |
03:01:41.79 |
+24:40:25.1 |
HIP 14080 |
27.35 |
| 2026-08-02 00:00 |
03:01:50.83 |
+24:41:30.2 |
HIP 14080 |
26.60 |
| 2026-08-02 12:00 |
03:01:59.74 |
+24:42:34.9 |
HIP 14080 |
26.02 |
| 2026-08-03 00:00 |
03:02:08.51 |
+24:43:39.1 |
HIP 14080 |
25.64 |
| 2026-08-03 12:00 |
03:02:17.15 |
+24:44:42.8 |
HIP 14080 |
25.44 |
| 2026-08-04 00:00 |
03:02:25.66 |
+24:45:46.1 |
HIP 14080 |
25.43 |
| 2026-08-04 12:00 |
03:02:34.03 |
+24:46:48.9 |
HIP 14080 |
25.60 |
| 2026-08-05 00:00 |
03:02:42.26 |
+24:47:51.3 |
HIP 14080 |
25.93 |
| 2026-08-05 12:00 |
03:02:50.35 |
+24:48:53.1 |
HIP 14080 |
26.42 |
| 2026-08-06 00:00 |
03:02:58.31 |
+24:49:54.5 |
HIP 14080 |
27.04 |
| 2026-08-06 12:00 |
03:03:06.12 |
+24:50:55.4 |
HIP 14080 |
27.78 |
| 2026-08-07 00:00 |
03:03:13.80 |
+24:51:55.9 |
HIP 14080 |
28.62 |
| 2026-08-07 12:00 |
03:03:21.34 |
+24:52:55.8 |
HIP 14080 |
29.56 |
| 2026-08-08 00:00 |
03:03:28.73 |
+24:53:55.2 |
HIP 14080 |
30.57 |
| 2026-08-08 12:00 |
03:03:35.99 |
+24:54:54.2 |
HIP 14080 |
31.64 |
| 2026-08-09 00:00 |
03:03:43.10 |
+24:55:52.6 |
HIP 14376 |
30.46 |
| 2026-08-09 12:00 |
03:03:50.07 |
+24:56:50.6 |
HIP 14376 |
28.63 |
| 2026-08-10 00:00 |
03:03:56.89 |
+24:57:48.0 |
HIP 14376 |
26.83 |
| 2026-08-10 12:00 |
03:04:03.57 |
+24:58:44.9 |
HIP 14376 |
25.07 |
| 2026-08-11 00:00 |
03:04:10.10 |
+24:59:41.3 |
HIP 14376 |
23.34 |
| 2026-08-11 12:00 |
03:04:16.49 |
+25:00:37.2 |
HIP 14376 |
21.64 |
| 2026-08-12 00:00 |
03:04:22.72 |
+25:01:32.6 |
HIP 14376 |
19.98 |
| 2026-08-12 12:00 |
03:04:28.82 |
+25:02:27.5 |
HIP 14376 |
18.35 |
| 2026-08-13 00:00 |
03:04:34.76 |
+25:03:21.8 |
HIP 14376 |
16.76 |
| 2026-08-13 12:00 |
03:04:40.55 |
+25:04:15.6 |
HIP 14376 |
15.20 |
| 2026-08-14 00:00 |
03:04:46.20 |
+25:05:08.8 |
HIP 14376 |
13.68 |
| 2026-08-14 12:00 |
03:04:51.69 |
+25:06:01.6 |
HIP 14376 |
12.20 |
| 2026-08-15 00:00 |
03:04:57.04 |
+25:06:53.8 |
HIP 14376 |
10.76 |
| 2026-08-15 12:00 |
03:05:02.23 |
+25:07:45.4 |
HIP 14376 |
9.36 |
| 2026-08-16 00:00 |
03:05:07.27 |
+25:08:36.5 |
HIP 14376 |
8.01 |
| 2026-08-16 12:00 |
03:05:12.16 |
+25:09:27.0 |
HIP 14376 |
6.72 |
| 2026-08-17 00:00 |
03:05:16.90 |
+25:10:17.0 |
HIP 14376 |
5.49 |
| 2026-08-17 12:00 |
03:05:21.49 |
+25:11:06.5 |
HIP 14376 |
4.37 |
| 2026-08-18 00:00 |
03:05:25.92 |
+25:11:55.4 |
HIP 14376 |
3.39 |
| 2026-08-18 12:00 |
03:05:30.20 |
+25:12:43.7 |
HIP 14376 |
2.70 |
| 2026-08-19 00:00 |
03:05:34.33 |
+25:13:31.5 |
HIP 14376 |
2.49 |