| Parameter |
Value |
| Designation |
481P/Lemmon-PANSTARRS |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2013-01-20T09:40:11.303040Z |
| Orbit solution date (soln_date, UTC) |
2025-01-02T20:13:07Z |
| Obs used |
58 |
| NEO |
- |
| M1 |
14.500 |
| K1 |
8.750 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2024-02-12T23:21:45.216000Z |
| Discovery magnitude (MPC) |
20.20 G |
| Discovery observatory (MPC) |
J04 · ESA Optical Ground Station, Tenerife |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2018-02-02.0000000 |
| e |
0.33653656 |
| q (au) |
3.174489 |
| a (au) |
4.784723 |
| i (deg) |
6.121394 |
| Ω (om, deg) |
94.508201 |
| ω (w, deg) |
352.744493 |
| M (ma, deg) |
173.143194 |
Magnitude
Scatter + Global Linear
$$
M_a = (10.456 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
10.456 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.500 |
| k |
1.000 |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
15:14:19.02 |
-12:14:41.7 |
HIP 74533 |
11.25 |
| 2026-03-26 12:00 |
15:14:10.44 |
-12:13:52.3 |
HIP 74533 |
10.60 |
| 2026-03-27 00:00 |
15:14:01.69 |
-12:13:02.3 |
HIP 74533 |
10.40 |
| 2026-03-27 12:00 |
15:13:52.77 |
-12:12:11.9 |
HIP 74533 |
10.71 |
| 2026-03-28 00:00 |
15:13:43.69 |
-12:11:20.9 |
HIP 74533 |
11.50 |
| 2026-03-28 12:00 |
15:13:34.43 |
-12:10:29.5 |
HIP 74533 |
12.71 |
| 2026-03-29 00:00 |
15:13:25.01 |
-12:09:37.7 |
HIP 74533 |
14.25 |
| 2026-03-29 12:00 |
15:13:15.43 |
-12:08:45.3 |
HIP 74533 |
16.05 |
| 2026-03-30 00:00 |
15:13:05.68 |
-12:07:52.5 |
HIP 74430 |
16.51 |
| 2026-03-30 12:00 |
15:12:55.77 |
-12:06:59.3 |
HIP 74430 |
16.64 |
| 2026-03-31 00:00 |
15:12:45.70 |
-12:06:05.6 |
HIP 74430 |
17.17 |
| 2026-03-31 12:00 |
15:12:35.47 |
-12:05:11.5 |
HIP 74430 |
18.08 |
| 2026-04-01 00:00 |
15:12:25.08 |
-12:04:17.0 |
HIP 74430 |
19.33 |
| 2026-04-01 12:00 |
15:12:14.54 |
-12:03:22.0 |
HIP 74430 |
20.87 |
| 2026-04-02 00:00 |
15:12:03.84 |
-12:02:26.6 |
HIP 74430 |
22.66 |
| 2026-04-02 12:00 |
15:11:52.99 |
-12:01:30.8 |
HIP 74430 |
24.66 |
| 2026-04-03 00:00 |
15:11:41.99 |
-12:00:34.7 |
HIP 74430 |
26.83 |
| 2026-04-03 12:00 |
15:11:30.83 |
-11:59:38.1 |
HIP 74430 |
29.14 |
| 2026-04-04 00:00 |
15:11:19.53 |
-11:58:41.1 |
HIP 74311 |
30.40 |
| 2026-04-04 12:00 |
15:11:08.08 |
-11:57:43.8 |
HIP 74311 |
29.61 |
| 2026-04-05 00:00 |
15:10:56.48 |
-11:56:46.1 |
HIP 74311 |
29.09 |
| 2026-04-05 12:00 |
15:10:44.74 |
-11:55:48.1 |
HIP 74194 |
26.79 |
| 2026-04-06 00:00 |
15:10:32.86 |
-11:54:49.6 |
HIP 74194 |
24.31 |
| 2026-04-06 12:00 |
15:10:20.83 |
-11:53:50.9 |
HIP 74127 |
21.56 |
| 2026-04-07 00:00 |
15:10:08.67 |
-11:52:51.8 |
HIP 74127 |
18.43 |
| 2026-04-07 12:00 |
15:09:56.37 |
-11:51:52.4 |
HIP 74127 |
15.26 |
| 2026-04-08 00:00 |
15:09:43.94 |
-11:50:52.6 |
HIP 74127 |
12.06 |
| 2026-04-08 12:00 |
15:09:31.37 |
-11:49:52.6 |
HIP 74127 |
8.83 |
| 2026-04-09 00:00 |
15:09:18.67 |
-11:48:52.2 |
HIP 74127 |
5.56 |
| 2026-04-09 12:00 |
15:09:05.84 |
-11:47:51.6 |
HIP 74127 |
2.27 |
| 2026-04-10 00:00 |
15:08:52.88 |
-11:46:50.7 |
HIP 74127 |
1.10 |
| 2026-04-10 12:00 |
15:08:39.79 |
-11:45:49.5 |
HIP 74127 |
4.44 |
| 2026-04-11 00:00 |
15:08:26.58 |
-11:44:48.0 |
HIP 74127 |
7.83 |
| 2026-04-11 12:00 |
15:08:13.25 |
-11:43:46.3 |
HIP 74048 |
6.12 |
| 2026-04-12 00:00 |
15:07:59.80 |
-11:42:44.4 |
HIP 74048 |
3.70 |
| 2026-04-12 12:00 |
15:07:46.23 |
-11:41:42.2 |
HIP 74048 |
3.73 |
| 2026-04-13 00:00 |
15:07:32.55 |
-11:40:39.8 |
HIP 74048 |
6.21 |
| 2026-04-13 12:00 |
15:07:18.75 |
-11:39:37.1 |
HIP 74048 |
9.41 |
| 2026-04-14 00:00 |
15:07:04.84 |
-11:38:34.3 |
HIP 74048 |
12.81 |
| 2026-04-14 12:00 |
15:06:50.82 |
-11:37:31.3 |
HIP 74048 |
16.31 |
| 2026-04-15 00:00 |
15:06:36.70 |
-11:36:28.1 |
HIP 74048 |
19.86 |
| 2026-04-15 12:00 |
15:06:22.46 |
-11:35:24.7 |
HIP 74048 |
23.47 |
| 2026-04-16 00:00 |
15:06:08.13 |
-11:34:21.2 |
HIP 73760 |
22.27 |