| 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
$$
M_a = (5.151 + 5.442\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
5.151 |
| n |
5.442 |
| gf |
0.885 |
| 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) |
| 2026-03-26 00:00 |
01:42:48.32 |
+17:43:00.8 |
HIP 8075 |
13.30 |
| 2026-03-26 12:00 |
01:43:08.93 |
+17:44:40.7 |
HIP 8075 |
8.28 |
| 2026-03-27 00:00 |
01:43:29.58 |
+17:46:20.9 |
HIP 8075 |
3.71 |
| 2026-03-27 12:00 |
01:43:50.25 |
+17:48:01.4 |
HIP 8075 |
3.60 |
| 2026-03-28 00:00 |
01:44:10.96 |
+17:49:42.1 |
HIP 8075 |
8.15 |
| 2026-03-28 12:00 |
01:44:31.70 |
+17:51:23.1 |
HIP 8075 |
13.20 |
| 2026-03-29 00:00 |
01:44:52.48 |
+17:53:04.3 |
HIP 8075 |
18.35 |
| 2026-03-29 12:00 |
01:45:13.28 |
+17:54:45.8 |
HIP 8075 |
23.54 |
| 2026-03-30 00:00 |
01:45:34.12 |
+17:56:27.6 |
HIP 8075 |
28.76 |
| 2026-03-30 12:00 |
01:45:54.98 |
+17:58:09.5 |
HIP 8075 |
33.99 |
| 2026-03-31 00:00 |
01:46:15.88 |
+17:59:51.7 |
HIP 8271 |
35.40 |
| 2026-03-31 12:00 |
01:46:36.80 |
+18:01:34.2 |
HIP 8271 |
36.81 |
| 2026-04-01 00:00 |
01:46:57.75 |
+18:03:16.8 |
HIP 8303 |
37.41 |
| 2026-04-01 12:00 |
01:47:18.72 |
+18:04:59.7 |
HIP 8489 |
35.36 |
| 2026-04-02 00:00 |
01:47:39.73 |
+18:06:42.8 |
HIP 8489 |
32.18 |
| 2026-04-02 12:00 |
01:48:00.76 |
+18:08:26.2 |
HIP 8489 |
29.61 |
| 2026-04-03 00:00 |
01:48:21.82 |
+18:10:09.7 |
HIP 8489 |
27.82 |
| 2026-04-03 12:00 |
01:48:42.90 |
+18:11:53.4 |
HIP 8489 |
26.97 |
| 2026-04-04 00:00 |
01:49:04.01 |
+18:13:37.4 |
HIP 8489 |
27.15 |
| 2026-04-04 12:00 |
01:49:25.14 |
+18:15:21.5 |
HIP 8489 |
28.35 |
| 2026-04-05 00:00 |
01:49:46.29 |
+18:17:05.9 |
HIP 8654 |
28.48 |
| 2026-04-05 12:00 |
01:50:07.47 |
+18:18:50.4 |
HIP 8654 |
23.24 |
| 2026-04-06 00:00 |
01:50:28.67 |
+18:20:35.1 |
HIP 8654 |
18.04 |
| 2026-04-06 12:00 |
01:50:49.89 |
+18:22:20.1 |
HIP 8654 |
12.94 |
| 2026-04-07 00:00 |
01:51:11.14 |
+18:24:05.2 |
HIP 8654 |
8.13 |
| 2026-04-07 12:00 |
01:51:32.40 |
+18:25:50.4 |
HIP 8654 |
4.65 |
| 2026-04-08 00:00 |
01:51:53.69 |
+18:27:35.9 |
HIP 8654 |
5.85 |
| 2026-04-08 12:00 |
01:52:15.00 |
+18:29:21.5 |
HIP 8654 |
10.20 |
| 2026-04-09 00:00 |
01:52:36.32 |
+18:31:07.3 |
HIP 8654 |
15.20 |
| 2026-04-09 12:00 |
01:52:57.67 |
+18:32:53.3 |
HIP 8654 |
20.39 |
| 2026-04-10 00:00 |
01:53:19.03 |
+18:34:39.4 |
HIP 8654 |
25.65 |
| 2026-04-10 12:00 |
01:53:40.41 |
+18:36:25.6 |
HIP 8654 |
30.95 |
| 2026-04-11 00:00 |
01:54:01.80 |
+18:38:12.1 |
HIP 9012 |
30.52 |
| 2026-04-11 12:00 |
01:54:23.22 |
+18:39:58.6 |
HIP 9012 |
26.72 |
| 2026-04-12 00:00 |
01:54:44.65 |
+18:41:45.3 |
HIP 9012 |
23.53 |
| 2026-04-12 12:00 |
01:55:06.09 |
+18:43:32.2 |
HIP 9012 |
21.26 |
| 2026-04-13 00:00 |
01:55:27.55 |
+18:45:19.2 |
HIP 9012 |
20.20 |
| 2026-04-13 12:00 |
01:55:49.03 |
+18:47:06.3 |
HIP 9012 |
20.55 |
| 2026-04-14 00:00 |
01:56:10.51 |
+18:48:53.6 |
HIP 9119 |
22.04 |
| 2026-04-14 12:00 |
01:56:32.01 |
+18:50:40.9 |
HIP 9119 |
16.74 |
| 2026-04-15 00:00 |
01:56:53.53 |
+18:52:28.4 |
HIP 9119 |
11.53 |
| 2026-04-15 12:00 |
01:57:15.05 |
+18:54:16.0 |
HIP 9119 |
6.61 |
| 2026-04-16 00:00 |
01:57:36.58 |
+18:56:03.8 |
HIP 9119 |
3.58 |