| Parameter |
Value |
| Designation |
507P/Lemmon |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2022-12-06T12:07:02.400960Z |
| Orbit solution date (soln_date, UTC) |
2025-08-01T17:26:05Z |
| Obs used |
99 |
| NEO |
- |
| M1 |
15.800 |
| K1 |
4.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2007-09-25T06:37:46.272000Z |
| Discovery magnitude (MPC) |
20.60 V |
| Discovery observatory (MPC) |
G96 · University of Arizona Mt. Lemmon Survey |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2019-04-20.0000000 |
| e |
0.56799400 |
| q (au) |
2.717068 |
| a (au) |
6.289421 |
| i (deg) |
17.095414 |
| Ω (om, deg) |
233.426223 |
| ω (w, deg) |
108.747547 |
| M (ma, deg) |
277.110996 |
Magnitude
Scatter + Global Linear
$$
M_a = (18.505 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
18.505 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.756 |
| 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
Finding Chart
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-09-20 00:00 |
08:34:52.26 |
+03:10:40.4 |
HIP 42140 |
10.47 |
| 2026-09-20 12:00 |
08:35:03.89 |
+03:09:08.0 |
HIP 42140 |
9.79 |
| 2026-09-21 00:00 |
08:35:15.45 |
+03:07:35.6 |
HIP 42140 |
10.18 |
| 2026-09-21 12:00 |
08:35:26.93 |
+03:06:03.1 |
HIP 42140 |
11.53 |
| 2026-09-22 00:00 |
08:35:38.33 |
+03:04:30.6 |
HIP 42140 |
13.54 |
| 2026-09-22 12:00 |
08:35:49.65 |
+03:02:58.0 |
HIP 42140 |
15.95 |
| 2026-09-23 00:00 |
08:36:00.89 |
+03:01:25.3 |
HIP 42140 |
18.60 |
| 2026-09-23 12:00 |
08:36:12.05 |
+02:59:52.6 |
HIP 42142 |
19.27 |
| 2026-09-24 00:00 |
08:36:23.13 |
+02:58:19.8 |
HIP 42142 |
19.98 |
| 2026-09-24 12:00 |
08:36:34.13 |
+02:56:47.0 |
HIP 42142 |
21.13 |
| 2026-09-25 00:00 |
08:36:45.05 |
+02:55:14.2 |
HIP 42142 |
22.65 |
| 2026-09-25 12:00 |
08:36:55.88 |
+02:53:41.3 |
HIP 42142 |
24.45 |
| 2026-09-26 00:00 |
08:37:06.63 |
+02:52:08.3 |
HIP 42142 |
26.48 |
| 2026-09-26 12:00 |
08:37:17.30 |
+02:50:35.4 |
HIP 42142 |
28.68 |
| 2026-09-27 00:00 |
08:37:27.89 |
+02:49:02.4 |
HIP 42142 |
31.01 |
| 2026-09-27 12:00 |
08:37:38.39 |
+02:47:29.4 |
HIP 42142 |
33.44 |
| 2026-09-28 00:00 |
08:37:48.80 |
+02:45:56.3 |
HIP 42142 |
35.94 |
| 2026-09-28 12:00 |
08:37:59.13 |
+02:44:23.3 |
HIP 42402 |
37.91 |
| 2026-09-29 00:00 |
08:38:09.38 |
+02:42:50.2 |
HIP 42426 |
37.07 |
| 2026-09-29 12:00 |
08:38:19.53 |
+02:41:17.2 |
HIP 42426 |
34.72 |
| 2026-09-30 00:00 |
08:38:29.60 |
+02:39:44.1 |
HIP 42426 |
32.48 |
| 2026-09-30 12:00 |
08:38:39.58 |
+02:38:11.0 |
HIP 42426 |
30.36 |
| 2026-10-01 00:00 |
08:38:49.48 |
+02:36:38.0 |
HIP 42426 |
28.40 |
| 2026-10-01 12:00 |
08:38:59.28 |
+02:35:04.9 |
HIP 42426 |
26.61 |
| 2026-10-02 00:00 |
08:39:09.00 |
+02:33:31.9 |
HIP 42426 |
25.03 |
| 2026-10-02 12:00 |
08:39:18.62 |
+02:31:58.9 |
HIP 42426 |
23.70 |
| 2026-10-03 00:00 |
08:39:28.16 |
+02:30:25.9 |
HIP 42426 |
22.64 |
| 2026-10-03 12:00 |
08:39:37.60 |
+02:28:52.9 |
HIP 42426 |
21.89 |
| 2026-10-04 00:00 |
08:39:46.95 |
+02:27:20.0 |
HIP 42426 |
21.49 |
| 2026-10-04 12:00 |
08:39:56.21 |
+02:25:47.1 |
HIP 42426 |
21.43 |
| 2026-10-05 00:00 |
08:40:05.38 |
+02:24:14.2 |
HIP 42426 |
21.71 |
| 2026-10-05 12:00 |
08:40:14.45 |
+02:22:41.4 |
HIP 42426 |
22.32 |
| 2026-10-06 00:00 |
08:40:23.42 |
+02:21:08.7 |
HIP 42648 |
22.51 |
| 2026-10-06 12:00 |
08:40:32.31 |
+02:19:36.0 |
HIP 42648 |
22.10 |
| 2026-10-07 00:00 |
08:40:41.09 |
+02:18:03.4 |
HIP 42648 |
22.04 |
| 2026-10-07 12:00 |
08:40:49.78 |
+02:16:30.8 |
HIP 42648 |
22.30 |
| 2026-10-08 00:00 |
08:40:58.37 |
+02:14:58.3 |
HIP 42537 |
22.18 |
| 2026-10-08 12:00 |
08:41:06.87 |
+02:13:25.9 |
HIP 42537 |
21.92 |
| 2026-10-09 00:00 |
08:41:15.27 |
+02:11:53.6 |
HIP 42537 |
21.97 |
| 2026-10-09 12:00 |
08:41:23.56 |
+02:10:21.4 |
HIP 42537 |
22.30 |
| 2026-10-10 00:00 |
08:41:31.76 |
+02:08:49.3 |
HIP 42537 |
22.90 |
| 2026-10-10 12:00 |
08:41:39.86 |
+02:07:17.3 |
HIP 42537 |
23.74 |
| 2026-10-11 00:00 |
08:41:47.86 |
+02:05:45.3 |
HIP 42537 |
24.79 |