| Parameter |
Value |
| Designation |
P/2025 A2 (PANSTARRS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2024-10-05T15:17:25.509120Z |
| Orbit solution date (soln_date, UTC) |
2025-04-11T14:45:09Z |
| Obs used |
66 |
| NEO |
- |
| M1 |
16.100 |
| K1 |
4.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2025-01-07T09:59:40.761600Z |
| Discovery magnitude (MPC) |
21.00 w |
| Discovery observatory (MPC) |
F51 · Pan-STARRS 1, Haleakala |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2025-01-22.0000000 |
| e |
0.32241041 |
| q (au) |
3.446251 |
| a (au) |
5.086044 |
| i (deg) |
20.732644 |
| Ω (om, deg) |
189.324202 |
| ω (w, deg) |
278.033834 |
| M (ma, deg) |
9.311389 |
Magnitude
Scatter + Global Linear
$$
M_a = (15.115 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
15.115 |
| n |
2.000 |
| gf |
0.999 |
| gb |
-1.000 |
| k |
1.000 |
| δ90 |
9.999 |
| 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) |
| 2026-09-20 00:00 |
13:21:47.95 |
-03:19:48.8 |
HIP 65081 |
27.78 |
| 2026-09-20 12:00 |
13:22:14.99 |
-03:21:50.0 |
HIP 65081 |
34.33 |
| 2026-09-21 00:00 |
13:22:42.06 |
-03:23:51.1 |
HIP 65335 |
37.47 |
| 2026-09-21 12:00 |
13:23:09.16 |
-03:25:52.2 |
HIP 65335 |
34.02 |
| 2026-09-22 00:00 |
13:23:36.29 |
-03:27:53.3 |
HIP 65335 |
31.77 |
| 2026-09-22 12:00 |
13:24:03.45 |
-03:29:54.3 |
HIP 65531 |
30.44 |
| 2026-09-23 00:00 |
13:24:30.64 |
-03:31:55.2 |
HIP 65531 |
24.58 |
| 2026-09-23 12:00 |
13:24:57.86 |
-03:33:56.1 |
HIP 65540 |
18.57 |
| 2026-09-24 00:00 |
13:25:25.10 |
-03:35:56.9 |
HIP 65540 |
11.49 |
| 2026-09-24 12:00 |
13:25:52.37 |
-03:37:57.7 |
HIP 65540 |
4.41 |
| 2026-09-25 00:00 |
13:26:19.67 |
-03:39:58.3 |
HIP 65540 |
2.76 |
| 2026-09-25 12:00 |
13:26:46.99 |
-03:41:58.9 |
HIP 65540 |
9.84 |
| 2026-09-26 00:00 |
13:27:14.34 |
-03:43:59.4 |
HIP 65540 |
16.94 |
| 2026-09-26 12:00 |
13:27:41.71 |
-03:45:59.8 |
HIP 65540 |
24.06 |
| 2026-09-27 00:00 |
13:28:09.11 |
-03:48:00.1 |
HIP 65540 |
31.18 |
| 2026-09-27 12:00 |
13:28:36.53 |
-03:50:00.3 |
HIP 65751 |
37.96 |
| 2026-09-28 00:00 |
13:29:03.98 |
-03:52:00.4 |
HIP 65940 |
33.67 |
| 2026-09-28 12:00 |
13:29:31.45 |
-03:54:00.4 |
HIP 65940 |
26.64 |
| 2026-09-29 00:00 |
13:29:58.94 |
-03:56:00.2 |
HIP 65940 |
19.69 |
| 2026-09-29 12:00 |
13:30:26.45 |
-03:58:00.0 |
HIP 65940 |
12.94 |
| 2026-09-30 00:00 |
13:30:53.99 |
-03:59:59.6 |
HIP 65940 |
7.03 |
| 2026-09-30 12:00 |
13:31:21.55 |
-04:01:59.1 |
HIP 65940 |
5.80 |
| 2026-10-01 00:00 |
13:31:49.13 |
-04:03:58.4 |
HIP 65940 |
10.98 |
| 2026-10-01 12:00 |
13:32:16.73 |
-04:05:57.6 |
HIP 65940 |
17.61 |
| 2026-10-02 00:00 |
13:32:44.35 |
-04:07:56.7 |
HIP 65940 |
24.54 |
| 2026-10-02 12:00 |
13:33:11.99 |
-04:09:55.6 |
HIP 66226 |
21.62 |
| 2026-10-03 00:00 |
13:33:39.65 |
-04:11:54.4 |
HIP 66226 |
14.96 |
| 2026-10-03 12:00 |
13:34:07.33 |
-04:13:52.9 |
HIP 66226 |
9.11 |
| 2026-10-04 00:00 |
13:34:35.03 |
-04:15:51.4 |
HIP 66226 |
6.73 |
| 2026-10-04 12:00 |
13:35:02.75 |
-04:17:49.6 |
HIP 66324 |
9.18 |
| 2026-10-05 00:00 |
13:35:30.48 |
-04:19:47.7 |
HIP 66324 |
3.62 |
| 2026-10-05 12:00 |
13:35:58.23 |
-04:21:45.6 |
HIP 66324 |
6.73 |
| 2026-10-06 00:00 |
13:36:26.00 |
-04:23:43.3 |
HIP 66324 |
13.45 |
| 2026-10-06 12:00 |
13:36:53.78 |
-04:25:40.8 |
HIP 66324 |
20.50 |
| 2026-10-07 00:00 |
13:37:21.58 |
-04:27:38.1 |
HIP 66450 |
20.61 |
| 2026-10-07 12:00 |
13:37:49.39 |
-04:29:35.2 |
HIP 66450 |
19.84 |
| 2026-10-08 00:00 |
13:38:17.22 |
-04:31:32.1 |
HIP 66450 |
21.59 |
| 2026-10-08 12:00 |
13:38:45.06 |
-04:33:28.7 |
HIP 66450 |
25.36 |
| 2026-10-09 00:00 |
13:39:12.92 |
-04:35:25.2 |
HIP 66675 |
27.73 |
| 2026-10-09 12:00 |
13:39:40.78 |
-04:37:21.4 |
HIP 66675 |
26.95 |
| 2026-10-10 00:00 |
13:40:08.66 |
-04:39:17.3 |
HIP 66675 |
28.05 |
| 2026-10-10 12:00 |
13:40:36.55 |
-04:41:13.1 |
HIP 66675 |
30.85 |
| 2026-10-11 00:00 |
13:41:04.45 |
-04:43:08.5 |
HIP 66706 |
33.05 |