| Parameter |
Value |
| Designation |
C/2024 J2 (Wierzchos) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2025-03-19T18:36:17.582400Z |
| Orbit solution date (soln_date, UTC) |
2026-03-11T21:13:02Z |
| Obs used |
451 |
| NEO |
- |
| M1 |
11.600 |
| K1 |
10.000 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2024-05-11T06:26:33.302400Z |
| Discovery magnitude (MPC) |
21.29 G |
| Discovery observatory (MPC) |
G96 · University of Arizona Mt. Lemmon Survey |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2025-02-11.0000000 |
| e |
0.98760800 |
| q (au) |
1.810945 |
| a (au) |
146.138176 |
| i (deg) |
79.296967 |
| Ω (om, deg) |
189.059198 |
| ω (w, deg) |
143.153599 |
| M (ma, deg) |
359.979483 |
Magnitude
Scatter + Global Linear
$$
M_a = (12.357 + 4.797\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
12.357 |
| n |
4.797 |
| gf |
0.995 |
| gb |
-0.712 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2024-03-12 |
2024-11-30 |
+3.8464 |
-1.845 |
| 2024-11-30 |
2025-02-05 |
-14.5390 |
+4.355 |
| 2025-06-26 |
2025-11-28 |
-5.8288 |
+2.402 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-06-01 00:00 |
04:14:51.93 |
-39:29:17.3 |
HIP 19898 |
16.31 |
| 2026-06-01 12:00 |
04:15:27.56 |
-39:30:37.3 |
HIP 19898 |
9.90 |
| 2026-06-02 00:00 |
04:16:03.16 |
-39:31:58.8 |
HIP 19898 |
5.24 |
| 2026-06-02 12:00 |
04:16:38.74 |
-39:33:21.9 |
HIP 19898 |
7.39 |
| 2026-06-03 00:00 |
04:17:14.28 |
-39:34:46.6 |
HIP 20061 |
10.14 |
| 2026-06-03 12:00 |
04:17:49.80 |
-39:36:12.9 |
HIP 20061 |
3.74 |
| 2026-06-04 00:00 |
04:18:25.29 |
-39:37:40.8 |
HIP 20061 |
4.82 |
| 2026-06-04 12:00 |
04:19:00.76 |
-39:39:10.2 |
HIP 20061 |
11.41 |
| 2026-06-05 00:00 |
04:19:36.19 |
-39:40:41.2 |
HIP 20061 |
18.31 |
| 2026-06-05 12:00 |
04:20:11.59 |
-39:42:13.8 |
HIP 20061 |
25.25 |
| 2026-06-06 00:00 |
04:20:46.96 |
-39:43:48.0 |
HIP 20061 |
32.21 |
| 2026-06-06 12:00 |
04:21:22.30 |
-39:45:23.8 |
HIP 20554 |
37.23 |
| 2026-06-07 00:00 |
04:21:57.60 |
-39:47:01.2 |
HIP 20554 |
30.56 |
| 2026-06-07 12:00 |
04:22:32.87 |
-39:48:40.1 |
HIP 20554 |
24.04 |
| 2026-06-08 00:00 |
04:23:08.11 |
-39:50:20.6 |
HIP 20554 |
17.85 |
| 2026-06-08 12:00 |
04:23:43.32 |
-39:52:02.7 |
HIP 20554 |
12.48 |
| 2026-06-09 00:00 |
04:24:18.49 |
-39:53:46.4 |
HIP 20554 |
9.45 |
| 2026-06-09 12:00 |
04:24:53.62 |
-39:55:31.7 |
HIP 20670 |
10.45 |
| 2026-06-10 00:00 |
04:25:28.72 |
-39:57:18.6 |
HIP 20670 |
7.49 |
| 2026-06-10 12:00 |
04:26:03.77 |
-39:59:07.1 |
HIP 20670 |
10.02 |
| 2026-06-11 00:00 |
04:26:38.80 |
-40:00:57.1 |
HIP 20795 |
13.72 |
| 2026-06-11 12:00 |
04:27:13.78 |
-40:02:48.8 |
HIP 20795 |
9.18 |
| 2026-06-12 00:00 |
04:27:48.72 |
-40:04:42.0 |
HIP 20795 |
8.72 |
| 2026-06-12 12:00 |
04:28:23.62 |
-40:06:36.8 |
HIP 20795 |
12.79 |
| 2026-06-13 00:00 |
04:28:58.48 |
-40:08:33.2 |
HIP 20795 |
18.63 |
| 2026-06-13 12:00 |
04:29:33.30 |
-40:10:31.2 |
HIP 21030 |
11.80 |
| 2026-06-14 00:00 |
04:30:08.08 |
-40:12:30.8 |
HIP 21030 |
4.90 |
| 2026-06-14 12:00 |
04:30:42.81 |
-40:14:31.9 |
HIP 21030 |
2.27 |
| 2026-06-15 00:00 |
04:31:17.50 |
-40:16:34.7 |
HIP 21030 |
9.07 |
| 2026-06-15 12:00 |
04:31:52.14 |
-40:18:39.0 |
HIP 21190 |
10.29 |
| 2026-06-16 00:00 |
04:32:26.73 |
-40:20:45.0 |
HIP 21190 |
8.41 |
| 2026-06-16 12:00 |
04:33:01.28 |
-40:22:52.5 |
HIP 21190 |
11.49 |
| 2026-06-17 00:00 |
04:33:35.78 |
-40:25:01.5 |
HIP 21190 |
17.02 |
| 2026-06-17 12:00 |
04:34:10.22 |
-40:27:12.2 |
HIP 21190 |
23.30 |
| 2026-06-18 00:00 |
04:34:44.62 |
-40:29:24.4 |
HIP 21320 |
20.63 |
| 2026-06-18 12:00 |
04:35:18.97 |
-40:31:38.2 |
HIP 21320 |
20.05 |
| 2026-06-19 00:00 |
04:35:53.27 |
-40:33:53.5 |
HIP 21541 |
18.40 |
| 2026-06-19 12:00 |
04:36:27.51 |
-40:36:10.5 |
HIP 21541 |
12.54 |
| 2026-06-20 00:00 |
04:37:01.70 |
-40:38:28.9 |
HIP 21541 |
8.47 |
| 2026-06-20 12:00 |
04:37:35.83 |
-40:40:48.9 |
HIP 21541 |
9.02 |
| 2026-06-21 00:00 |
04:38:09.91 |
-40:43:10.5 |
HIP 21613 |
8.20 |
| 2026-06-21 12:00 |
04:38:43.94 |
-40:45:33.6 |
HIP 21613 |
10.88 |
| 2026-06-22 00:00 |
04:39:17.91 |
-40:47:58.2 |
HIP 21613 |
16.27 |