| Parameter |
Value |
| Designation |
457P/Lemmon-PANSTARRS |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2020-05-04T06:45:39.692160Z |
| Orbit solution date (soln_date, UTC) |
2025-01-02T20:13:03Z |
| Obs used |
136 |
| NEO |
- |
| M1 |
6.800 |
| K1 |
36.250 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2016-07-03T13:38:06.950400Z |
| Discovery magnitude (MPC) |
23.20 T |
| Discovery observatory (MPC) |
T09 · Subaru Telescope, Maunakea |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2020-04-13.0000000 |
| e |
0.11977371 |
| q (au) |
2.329381 |
| a (au) |
2.646344 |
| i (deg) |
5.222268 |
| Ω (om, deg) |
176.012536 |
| ω (w, deg) |
104.953942 |
| M (ma, deg) |
355.127619 |
Magnitude
Scatter + Global Linear
$$
M_a = (20.000 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
20.000 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.721 |
| k |
0.978 |
| 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) |
| 2026-05-12 00:00 |
04:20:25.55 |
+17:36:25.0 |
HIP 20146 |
19.14 |
| 2026-05-12 12:00 |
04:21:13.20 |
+17:38:21.2 |
HIP 20455 |
25.18 |
| 2026-05-13 00:00 |
04:22:00.88 |
+17:40:16.5 |
HIP 20455 |
15.24 |
| 2026-05-13 12:00 |
04:22:48.59 |
+17:42:10.8 |
HIP 20455 |
9.79 |
| 2026-05-14 00:00 |
04:23:36.34 |
+17:44:04.2 |
HIP 20455 |
14.99 |
| 2026-05-14 12:00 |
04:24:24.12 |
+17:45:56.7 |
HIP 20563 |
14.34 |
| 2026-05-15 00:00 |
04:25:11.93 |
+17:47:48.3 |
HIP 20648 |
8.90 |
| 2026-05-15 12:00 |
04:25:59.77 |
+17:49:38.9 |
HIP 20648 |
9.43 |
| 2026-05-16 00:00 |
04:26:47.64 |
+17:51:28.6 |
HIP 20679 |
17.21 |
| 2026-05-16 12:00 |
04:27:35.54 |
+17:53:17.3 |
HIP 20780 |
20.51 |
| 2026-05-17 00:00 |
04:28:23.47 |
+17:55:05.1 |
HIP 20948 |
16.23 |
| 2026-05-17 12:00 |
04:29:11.43 |
+17:56:51.9 |
HIP 20951 |
5.79 |
| 2026-05-18 00:00 |
04:29:59.42 |
+17:58:37.8 |
HIP 20951 |
8.33 |
| 2026-05-18 12:00 |
04:30:47.43 |
+18:00:22.7 |
HIP 20990 |
16.95 |
| 2026-05-19 00:00 |
04:31:35.47 |
+18:02:06.7 |
HIP 21173 |
15.43 |
| 2026-05-19 12:00 |
04:32:23.53 |
+18:03:49.7 |
HIP 21173 |
9.16 |
| 2026-05-20 00:00 |
04:33:11.62 |
+18:05:31.7 |
HIP 21251 |
6.81 |
| 2026-05-20 12:00 |
04:33:59.73 |
+18:07:12.8 |
HIP 21251 |
8.87 |
| 2026-05-21 00:00 |
04:34:47.86 |
+18:08:52.8 |
HIP 21350 |
15.97 |
| 2026-05-21 12:00 |
04:35:36.02 |
+18:10:31.9 |
HIP 21350 |
17.59 |
| 2026-05-22 00:00 |
04:36:24.19 |
+18:12:10.1 |
HIP 21517 |
23.68 |
| 2026-05-22 12:00 |
04:37:12.39 |
+18:13:47.2 |
HIP 21517 |
18.80 |
| 2026-05-23 00:00 |
04:38:00.61 |
+18:15:23.4 |
HIP 21517 |
20.34 |
| 2026-05-23 12:00 |
04:38:48.85 |
+18:16:58.5 |
HIP 21517 |
27.23 |
| 2026-05-24 00:00 |
04:39:37.11 |
+18:18:32.7 |
HIP 21621 |
29.91 |
| 2026-05-24 12:00 |
04:40:25.38 |
+18:20:05.9 |
HIP 21621 |
36.15 |
| 2026-05-25 00:00 |
04:41:13.68 |
+18:21:38.1 |
HIP 21926 |
26.73 |
| 2026-05-25 12:00 |
04:42:01.99 |
+18:23:09.3 |
HIP 21926 |
18.73 |
| 2026-05-26 00:00 |
04:42:50.32 |
+18:24:39.5 |
HIP 21926 |
15.95 |
| 2026-05-26 12:00 |
04:43:38.67 |
+18:26:08.7 |
HIP 21946 |
18.78 |
| 2026-05-27 00:00 |
04:44:27.03 |
+18:27:37.0 |
HIP 21946 |
25.30 |
| 2026-05-27 12:00 |
04:45:15.41 |
+18:29:04.2 |
HIP 22176 |
20.91 |
| 2026-05-28 00:00 |
04:46:03.80 |
+18:30:30.4 |
HIP 22176 |
13.93 |
| 2026-05-28 12:00 |
04:46:52.21 |
+18:31:55.6 |
HIP 22176 |
14.78 |
| 2026-05-29 00:00 |
04:47:40.64 |
+18:33:19.8 |
HIP 22311 |
9.19 |
| 2026-05-29 12:00 |
04:48:29.07 |
+18:34:43.0 |
HIP 22311 |
2.43 |
| 2026-05-30 00:00 |
04:49:17.53 |
+18:36:05.2 |
HIP 22380 |
4.10 |
| 2026-05-30 12:00 |
04:50:05.99 |
+18:37:26.3 |
HIP 22380 |
14.85 |
| 2026-05-31 00:00 |
04:50:54.47 |
+18:38:46.5 |
HIP 22565 |
13.37 |
| 2026-05-31 12:00 |
04:51:42.96 |
+18:40:05.6 |
HIP 22565 |
11.39 |
| 2026-06-01 00:00 |
04:52:31.46 |
+18:41:23.7 |
HIP 22654 |
18.52 |
| 2026-06-01 12:00 |
04:53:19.98 |
+18:42:40.9 |
HIP 22654 |
21.73 |
| 2026-06-02 00:00 |
04:54:08.50 |
+18:43:56.9 |
HIP 22745 |
21.87 |