| Parameter |
Value |
| Designation |
302P/Lemmon-PANSTARRS |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2025-03-08T21:40:03.639360Z |
| Orbit solution date (soln_date, UTC) |
2026-04-14T13:42:34Z |
| Obs used |
993 |
| NEO |
- |
| M1 |
6.900 |
| K1 |
16.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2023-08-18.0000000 |
| e |
0.23011984 |
| q (au) |
3.288834 |
| a (au) |
4.271878 |
| i (deg) |
6.033733 |
| Ω (om, deg) |
121.724408 |
| ω (w, deg) |
208.543535 |
| M (ma, deg) |
296.494117 |
Magnitude
Scatter + Global Linear
$$
M_a = (6.397 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
6.397 |
| n |
6.000 |
| gf |
0.913 |
| gb |
-0.909 |
| k |
1.000 |
| δ90 |
4.998 |
| 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 |
| 2023-03-27 |
2024-12-03 |
+19.3467 |
-9.989 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
04:17:25.44 |
+16:08:32.4 |
HIP 19960 |
9.82 |
| 2026-07-29 12:00 |
04:17:52.52 |
+16:09:20.4 |
HIP 20082 |
7.57 |
| 2026-07-30 00:00 |
04:18:19.47 |
+16:10:07.6 |
HIP 20082 |
4.82 |
| 2026-07-30 12:00 |
04:18:46.30 |
+16:10:54.1 |
HIP 20082 |
8.58 |
| 2026-07-31 00:00 |
04:19:13.00 |
+16:11:39.9 |
HIP 20082 |
14.40 |
| 2026-07-31 12:00 |
04:19:39.57 |
+16:12:24.9 |
HIP 20215 |
19.29 |
| 2026-08-01 00:00 |
04:20:06.00 |
+16:13:09.3 |
HIP 20215 |
18.40 |
| 2026-08-01 12:00 |
04:20:32.31 |
+16:13:52.8 |
HIP 20290 |
18.64 |
| 2026-08-02 00:00 |
04:20:58.48 |
+16:14:35.7 |
HIP 20290 |
18.58 |
| 2026-08-02 12:00 |
04:21:24.52 |
+16:15:17.8 |
HIP 20290 |
20.54 |
| 2026-08-03 00:00 |
04:21:50.43 |
+16:15:59.2 |
HIP 20290 |
24.01 |
| 2026-08-03 12:00 |
04:22:16.19 |
+16:16:39.8 |
HIP 20290 |
28.42 |
| 2026-08-04 00:00 |
04:22:41.83 |
+16:17:19.7 |
HIP 20441 |
30.14 |
| 2026-08-04 12:00 |
04:23:07.32 |
+16:17:58.9 |
HIP 20484 |
28.97 |
| 2026-08-05 00:00 |
04:23:32.67 |
+16:18:37.4 |
HIP 20484 |
28.08 |
| 2026-08-05 12:00 |
04:23:57.88 |
+16:19:15.1 |
HIP 20484 |
28.50 |
| 2026-08-06 00:00 |
04:24:22.95 |
+16:19:52.2 |
HIP 20605 |
28.04 |
| 2026-08-06 12:00 |
04:24:47.88 |
+16:20:28.5 |
HIP 20661 |
26.78 |
| 2026-08-07 00:00 |
04:25:12.66 |
+16:21:04.0 |
HIP 20661 |
25.30 |
| 2026-08-07 12:00 |
04:25:37.30 |
+16:21:38.9 |
HIP 20661 |
25.18 |
| 2026-08-08 00:00 |
04:26:01.79 |
+16:22:13.0 |
HIP 20741 |
24.39 |
| 2026-08-08 12:00 |
04:26:26.13 |
+16:22:46.5 |
HIP 20741 |
22.29 |
| 2026-08-09 00:00 |
04:26:50.32 |
+16:23:19.2 |
HIP 20741 |
21.64 |
| 2026-08-09 12:00 |
04:27:14.36 |
+16:23:51.2 |
HIP 20877 |
17.42 |
| 2026-08-10 00:00 |
04:27:38.24 |
+16:24:22.5 |
HIP 20877 |
11.88 |
| 2026-08-10 12:00 |
04:28:01.98 |
+16:24:53.1 |
HIP 20877 |
6.72 |
| 2026-08-11 00:00 |
04:28:25.55 |
+16:25:22.9 |
HIP 20877 |
3.81 |
| 2026-08-11 12:00 |
04:28:48.97 |
+16:25:52.1 |
HIP 20877 |
6.91 |
| 2026-08-12 00:00 |
04:29:12.24 |
+16:26:20.6 |
HIP 20877 |
11.99 |
| 2026-08-12 12:00 |
04:29:35.34 |
+16:26:48.3 |
HIP 20978 |
14.59 |
| 2026-08-13 00:00 |
04:29:58.28 |
+16:27:15.4 |
HIP 20978 |
13.12 |
| 2026-08-13 12:00 |
04:30:21.06 |
+16:27:41.8 |
HIP 20978 |
13.86 |
| 2026-08-14 00:00 |
04:30:43.68 |
+16:28:07.5 |
HIP 20978 |
16.48 |
| 2026-08-14 12:00 |
04:31:06.13 |
+16:28:32.5 |
HIP 21029 |
18.62 |
| 2026-08-15 00:00 |
04:31:28.42 |
+16:28:56.8 |
HIP 21029 |
21.74 |
| 2026-08-15 12:00 |
04:31:50.54 |
+16:29:20.4 |
HIP 21053 |
25.52 |
| 2026-08-16 00:00 |
04:32:12.49 |
+16:29:43.4 |
HIP 21257 |
22.97 |
| 2026-08-16 12:00 |
04:32:34.28 |
+16:30:05.6 |
HIP 21257 |
18.67 |
| 2026-08-17 00:00 |
04:32:55.89 |
+16:30:27.2 |
HIP 21257 |
14.98 |
| 2026-08-17 12:00 |
04:33:17.34 |
+16:30:48.2 |
HIP 21257 |
12.44 |
| 2026-08-18 00:00 |
04:33:38.61 |
+16:31:08.4 |
HIP 21257 |
11.74 |
| 2026-08-18 12:00 |
04:33:59.71 |
+16:31:28.0 |
HIP 21257 |
13.13 |
| 2026-08-19 00:00 |
04:34:20.63 |
+16:31:46.9 |
HIP 21257 |
16.04 |