| Parameter |
Value |
| Designation |
C/2023 X2 (Lemmon) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2025-12-27T20:41:54.911040Z |
| Orbit solution date (soln_date, UTC) |
2026-05-08T13:42:12Z |
| Obs used |
554 |
| NEO |
- |
| M1 |
7.300 |
| K1 |
10.250 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2023-12-04T08:26:50.467200Z |
| Discovery magnitude (MPC) |
19.74 G |
| Discovery observatory (MPC) |
G96 · Mt. Lemmon Survey |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2025-02-17.0000000 |
| e |
1.00053030 |
| q (au) |
5.089611 |
| a (au) |
-9597.528695 |
| i (deg) |
76.988193 |
| Ω (om, deg) |
66.307303 |
| ω (w, deg) |
64.727029 |
| M (ma, deg) |
-0.000329 |
Magnitude
Scatter + Global Linear
$$
M_a = (8.570 + 5.117\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
8.570 |
| n |
5.117 |
| gf |
1.000 |
| gb |
-0.759 |
| k |
0.800 |
| 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
Finding Chart
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
15:56:26.38 |
+88:06:13.4 |
HIP 79176 |
25.15 |
| 2026-05-12 12:00 |
15:46:40.27 |
+88:03:20.6 |
HIP 79176 |
29.20 |
| 2026-05-13 00:00 |
15:37:23.24 |
+88:00:13.3 |
HIP 79176 |
33.76 |
| 2026-05-13 12:00 |
15:28:35.42 |
+87:56:52.2 |
HIP 75576 |
30.78 |
| 2026-05-14 00:00 |
15:20:16.57 |
+87:53:18.4 |
HIP 75576 |
27.43 |
| 2026-05-14 12:00 |
15:12:26.07 |
+87:49:32.6 |
HIP 75576 |
24.95 |
| 2026-05-15 00:00 |
15:05:03.08 |
+87:45:35.7 |
HIP 75576 |
23.61 |
| 2026-05-15 12:00 |
14:58:06.56 |
+87:41:28.5 |
HIP 75576 |
23.64 |
| 2026-05-16 00:00 |
14:51:35.34 |
+87:37:11.7 |
HIP 75576 |
25.03 |
| 2026-05-16 12:00 |
14:45:28.18 |
+87:32:45.9 |
HIP 71725 |
20.19 |
| 2026-05-17 00:00 |
14:39:43.79 |
+87:28:11.8 |
HIP 71725 |
15.32 |
| 2026-05-17 12:00 |
14:34:20.90 |
+87:23:29.9 |
HIP 71725 |
11.42 |
| 2026-05-18 00:00 |
14:29:18.24 |
+87:18:40.9 |
HIP 71725 |
9.78 |
| 2026-05-18 12:00 |
14:24:34.56 |
+87:13:45.2 |
HIP 71725 |
11.47 |
| 2026-05-19 00:00 |
14:20:08.68 |
+87:08:43.1 |
HIP 71725 |
15.45 |
| 2026-05-19 12:00 |
14:15:59.45 |
+87:03:35.2 |
HIP 71725 |
20.44 |
| 2026-05-20 00:00 |
14:12:05.82 |
+86:58:21.9 |
HIP 71725 |
25.88 |
| 2026-05-20 12:00 |
14:08:26.75 |
+86:53:03.3 |
HIP 71725 |
31.55 |
| 2026-05-21 00:00 |
14:05:01.30 |
+86:47:40.0 |
HIP 67951 |
36.86 |
| 2026-05-21 12:00 |
14:01:48.57 |
+86:42:12.1 |
HIP 65864 |
36.77 |
| 2026-05-22 00:00 |
13:58:47.72 |
+86:36:39.8 |
HIP 65864 |
31.62 |
| 2026-05-22 12:00 |
13:55:57.99 |
+86:31:03.6 |
HIP 65864 |
26.89 |
| 2026-05-23 00:00 |
13:53:18.64 |
+86:25:23.5 |
HIP 65864 |
22.86 |
| 2026-05-23 12:00 |
13:50:49.02 |
+86:19:39.8 |
HIP 65864 |
19.99 |
| 2026-05-24 00:00 |
13:48:28.48 |
+86:13:52.6 |
HIP 65864 |
18.84 |
| 2026-05-24 12:00 |
13:46:16.46 |
+86:08:02.1 |
HIP 65864 |
19.73 |
| 2026-05-25 00:00 |
13:44:12.42 |
+86:02:08.5 |
HIP 67437 |
18.11 |
| 2026-05-25 12:00 |
13:42:15.86 |
+85:56:12.0 |
HIP 67437 |
13.65 |
| 2026-05-26 00:00 |
13:40:26.32 |
+85:50:12.5 |
HIP 67437 |
11.09 |
| 2026-05-26 12:00 |
13:38:43.37 |
+85:44:10.4 |
HIP 67437 |
11.76 |
| 2026-05-27 00:00 |
13:37:06.62 |
+85:38:05.6 |
HIP 67437 |
15.28 |
| 2026-05-27 12:00 |
13:35:35.69 |
+85:31:58.3 |
HIP 65572 |
19.06 |
| 2026-05-28 00:00 |
13:34:10.24 |
+85:25:48.6 |
HIP 65572 |
13.24 |
| 2026-05-28 12:00 |
13:32:49.96 |
+85:19:36.5 |
HIP 65572 |
8.32 |
| 2026-05-29 00:00 |
13:31:34.54 |
+85:13:22.2 |
HIP 65572 |
6.77 |
| 2026-05-29 12:00 |
13:30:23.72 |
+85:07:05.8 |
HIP 65572 |
10.29 |
| 2026-05-30 00:00 |
13:29:17.24 |
+85:00:47.2 |
HIP 65572 |
15.81 |
| 2026-05-30 12:00 |
13:28:14.85 |
+84:54:26.6 |
HIP 64861 |
18.36 |
| 2026-05-31 00:00 |
13:27:16.34 |
+84:48:04.0 |
HIP 64861 |
14.08 |
| 2026-05-31 12:00 |
13:26:21.50 |
+84:41:39.5 |
HIP 64861 |
12.06 |
| 2026-06-01 00:00 |
13:25:30.13 |
+84:35:13.2 |
HIP 64861 |
13.37 |
| 2026-06-01 12:00 |
13:24:42.05 |
+84:28:45.0 |
HIP 64861 |
17.29 |
| 2026-06-02 00:00 |
13:23:57.10 |
+84:22:15.1 |
HIP 64861 |
22.53 |