| Parameter |
Value |
| Designation |
C/2018 KJ3 (Lemmon) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2019-09-09T23:33:42.448320Z |
| Orbit solution date (soln_date, UTC) |
2021-09-04T23:42:57Z |
| Obs used |
465 |
| NEO |
- |
| M1 |
6.400 |
| K1 |
13.500 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2018-08-10.0000000 |
| e |
0.99581434 |
| q (au) |
3.627197 |
| a (au) |
866.577156 |
| i (deg) |
136.667328 |
| Ω (om, deg) |
91.587697 |
| ω (w, deg) |
217.709783 |
| M (ma, deg) |
359.984701 |
Magnitude
Scatter + Global Linear
$$
M_a = (H_0 + n\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
- |
| n |
- |
| gf |
- |
| gb |
- |
| k |
- |
| δ90 |
- |
| 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) |
| 2026-09-20 00:00 |
07:06:33.99 |
+11:46:32.2 |
HIP 34157 |
30.24 |
| 2026-09-20 12:00 |
07:06:35.20 |
+11:46:22.6 |
HIP 34157 |
30.57 |
| 2026-09-21 00:00 |
07:06:36.36 |
+11:46:13.1 |
HIP 34157 |
30.89 |
| 2026-09-21 12:00 |
07:06:37.46 |
+11:46:03.6 |
HIP 34157 |
31.20 |
| 2026-09-22 00:00 |
07:06:38.51 |
+11:45:54.2 |
HIP 34157 |
31.50 |
| 2026-09-22 12:00 |
07:06:39.50 |
+11:45:44.8 |
HIP 34157 |
31.79 |
| 2026-09-23 00:00 |
07:06:40.44 |
+11:45:35.5 |
HIP 34157 |
32.06 |
| 2026-09-23 12:00 |
07:06:41.33 |
+11:45:26.2 |
HIP 34157 |
32.33 |
| 2026-09-24 00:00 |
07:06:42.16 |
+11:45:16.9 |
HIP 34157 |
32.58 |
| 2026-09-24 12:00 |
07:06:42.94 |
+11:45:07.7 |
HIP 34157 |
32.83 |
| 2026-09-25 00:00 |
07:06:43.66 |
+11:44:58.5 |
HIP 34157 |
33.06 |
| 2026-09-25 12:00 |
07:06:44.33 |
+11:44:49.4 |
HIP 34157 |
33.29 |
| 2026-09-26 00:00 |
07:06:44.94 |
+11:44:40.3 |
HIP 34189 |
33.36 |
| 2026-09-26 12:00 |
07:06:45.49 |
+11:44:31.3 |
HIP 34189 |
33.33 |
| 2026-09-27 00:00 |
07:06:46.00 |
+11:44:22.3 |
HIP 34189 |
33.28 |
| 2026-09-27 12:00 |
07:06:46.44 |
+11:44:13.4 |
HIP 34189 |
33.23 |
| 2026-09-28 00:00 |
07:06:46.83 |
+11:44:04.5 |
HIP 34189 |
33.18 |
| 2026-09-28 12:00 |
07:06:47.17 |
+11:43:55.7 |
HIP 34189 |
33.11 |
| 2026-09-29 00:00 |
07:06:47.44 |
+11:43:47.0 |
HIP 34189 |
33.04 |
| 2026-09-29 12:00 |
07:06:47.67 |
+11:43:38.3 |
HIP 34189 |
32.96 |
| 2026-09-30 00:00 |
07:06:47.83 |
+11:43:29.7 |
HIP 34189 |
32.88 |
| 2026-09-30 12:00 |
07:06:47.94 |
+11:43:21.1 |
HIP 34189 |
32.78 |
| 2026-10-01 00:00 |
07:06:47.99 |
+11:43:12.6 |
HIP 34189 |
32.68 |
| 2026-10-01 12:00 |
07:06:47.99 |
+11:43:04.2 |
HIP 34189 |
32.58 |
| 2026-10-02 00:00 |
07:06:47.92 |
+11:42:55.8 |
HIP 34189 |
32.46 |
| 2026-10-02 12:00 |
07:06:47.81 |
+11:42:47.5 |
HIP 34189 |
32.33 |
| 2026-10-03 00:00 |
07:06:47.63 |
+11:42:39.3 |
HIP 34189 |
32.20 |
| 2026-10-03 12:00 |
07:06:47.40 |
+11:42:31.1 |
HIP 34189 |
32.06 |
| 2026-10-04 00:00 |
07:06:47.10 |
+11:42:23.0 |
HIP 34189 |
31.91 |
| 2026-10-04 12:00 |
07:06:46.75 |
+11:42:15.0 |
HIP 34189 |
31.76 |
| 2026-10-05 00:00 |
07:06:46.35 |
+11:42:07.1 |
HIP 34189 |
31.59 |
| 2026-10-05 12:00 |
07:06:45.88 |
+11:41:59.3 |
HIP 34189 |
31.42 |
| 2026-10-06 00:00 |
07:06:45.36 |
+11:41:51.5 |
HIP 34189 |
31.23 |
| 2026-10-06 12:00 |
07:06:44.77 |
+11:41:43.8 |
HIP 34189 |
31.04 |
| 2026-10-07 00:00 |
07:06:44.13 |
+11:41:36.2 |
HIP 34189 |
30.85 |
| 2026-10-07 12:00 |
07:06:43.43 |
+11:41:28.7 |
HIP 34189 |
30.64 |
| 2026-10-08 00:00 |
07:06:42.67 |
+11:41:21.2 |
HIP 34189 |
30.42 |
| 2026-10-08 12:00 |
07:06:41.85 |
+11:41:13.9 |
HIP 34189 |
30.20 |
| 2026-10-09 00:00 |
07:06:40.98 |
+11:41:06.6 |
HIP 34189 |
29.97 |
| 2026-10-09 12:00 |
07:06:40.04 |
+11:40:59.5 |
HIP 34189 |
29.73 |
| 2026-10-10 00:00 |
07:06:39.04 |
+11:40:52.4 |
HIP 34189 |
29.49 |
| 2026-10-10 12:00 |
07:06:37.99 |
+11:40:45.4 |
HIP 34189 |
29.23 |
| 2026-10-11 00:00 |
07:06:36.87 |
+11:40:38.6 |
HIP 34189 |
28.97 |