C/2007 K1 (Lemmon)
| Parameter |
Value |
| Designation |
C/2007 K1 (Lemmon) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2007-05-07T15:34:22.368000Z |
| Orbit solution date (soln_date, UTC) |
2022-06-20T23:12:31Z |
| Obs used |
141 |
| NEO |
- |
| M1 |
11.000 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2007-06-26.0000000 |
| e |
0.97872535 |
| q (au) |
9.239049 |
| a (au) |
434.274942 |
| i (deg) |
108.433102 |
| Ω (om, deg) |
294.661115 |
| ω (w, deg) |
51.970917 |
| M (ma, deg) |
0.005375 |
Magnitude
Scatter + Global Linear
$$
M_a = (9.857 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
9.857 |
| n |
2.000 |
| 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) |
| 2026-02-03 00:00 |
08:10:13.80 |
+31:31:23.2 |
HIP 40103 |
21.06 |
| 2026-02-03 12:00 |
08:10:09.27 |
+31:31:25.8 |
HIP 40103 |
21.85 |
| 2026-02-04 00:00 |
08:10:04.75 |
+31:31:28.3 |
HIP 40103 |
22.65 |
| 2026-02-04 12:00 |
08:10:00.23 |
+31:31:30.7 |
HIP 40103 |
23.47 |
| 2026-02-05 00:00 |
08:09:55.73 |
+31:31:32.9 |
HIP 40103 |
24.29 |
| 2026-02-05 12:00 |
08:09:51.24 |
+31:31:35.0 |
HIP 40103 |
25.11 |
| 2026-02-06 00:00 |
08:09:46.76 |
+31:31:37.0 |
HIP 40103 |
25.94 |
| 2026-02-06 12:00 |
08:09:42.30 |
+31:31:38.8 |
HIP 39767 |
26.15 |
| 2026-02-07 00:00 |
08:09:37.84 |
+31:31:40.6 |
HIP 39767 |
25.20 |
| 2026-02-07 12:00 |
08:09:33.40 |
+31:31:42.1 |
HIP 39767 |
24.25 |
| 2026-02-08 00:00 |
08:09:28.97 |
+31:31:43.6 |
HIP 39767 |
23.31 |
| 2026-02-08 12:00 |
08:09:24.56 |
+31:31:44.9 |
HIP 39767 |
22.37 |
| 2026-02-09 00:00 |
08:09:20.16 |
+31:31:46.0 |
HIP 39767 |
21.43 |
| 2026-02-09 12:00 |
08:09:15.77 |
+31:31:47.1 |
HIP 39767 |
20.50 |
| 2026-02-10 00:00 |
08:09:11.39 |
+31:31:48.0 |
HIP 39767 |
19.56 |
| 2026-02-10 12:00 |
08:09:07.03 |
+31:31:48.7 |
HIP 39767 |
18.64 |
| 2026-02-11 00:00 |
08:09:02.69 |
+31:31:49.3 |
HIP 39767 |
17.71 |
| 2026-02-11 12:00 |
08:08:58.36 |
+31:31:49.8 |
HIP 39767 |
16.79 |
| 2026-02-12 00:00 |
08:08:54.05 |
+31:31:50.2 |
HIP 39767 |
15.88 |
| 2026-02-12 12:00 |
08:08:49.75 |
+31:31:50.4 |
HIP 39767 |
14.96 |
| 2026-02-13 00:00 |
08:08:45.47 |
+31:31:50.4 |
HIP 39767 |
14.05 |
| 2026-02-13 12:00 |
08:08:41.21 |
+31:31:50.4 |
HIP 39767 |
13.15 |
| 2026-02-14 00:00 |
08:08:36.96 |
+31:31:50.1 |
HIP 39767 |
12.25 |
| 2026-02-14 12:00 |
08:08:32.73 |
+31:31:49.8 |
HIP 39767 |
11.35 |
| 2026-02-15 00:00 |
08:08:28.52 |
+31:31:49.3 |
HIP 39767 |
10.46 |
| 2026-02-15 12:00 |
08:08:24.32 |
+31:31:48.7 |
HIP 39767 |
9.58 |
| 2026-02-16 00:00 |
08:08:20.15 |
+31:31:47.9 |
HIP 39767 |
8.70 |
| 2026-02-16 12:00 |
08:08:15.99 |
+31:31:46.9 |
HIP 39767 |
7.83 |
| 2026-02-17 00:00 |
08:08:11.85 |
+31:31:45.9 |
HIP 39767 |
6.96 |
| 2026-02-17 12:00 |
08:08:07.74 |
+31:31:44.7 |
HIP 39767 |
6.11 |
| 2026-02-18 00:00 |
08:08:03.64 |
+31:31:43.3 |
HIP 39767 |
5.27 |
| 2026-02-18 12:00 |
08:07:59.56 |
+31:31:41.8 |
HIP 39767 |
4.44 |
| 2026-02-19 00:00 |
08:07:55.50 |
+31:31:40.2 |
HIP 39767 |
3.64 |
| 2026-02-19 12:00 |
08:07:51.46 |
+31:31:38.4 |
HIP 39767 |
2.88 |
| 2026-02-20 00:00 |
08:07:47.45 |
+31:31:36.5 |
HIP 39767 |
2.20 |
| 2026-02-20 12:00 |
08:07:43.45 |
+31:31:34.5 |
HIP 39767 |
1.70 |
| 2026-02-21 00:00 |
08:07:39.48 |
+31:31:32.3 |
HIP 39767 |
1.55 |
| 2026-02-21 12:00 |
08:07:35.53 |
+31:31:29.9 |
HIP 39767 |
1.83 |
| 2026-02-22 00:00 |
08:07:31.60 |
+31:31:27.4 |
HIP 39767 |
2.38 |
| 2026-02-22 12:00 |
08:07:27.69 |
+31:31:24.8 |
HIP 39767 |
3.07 |
| 2026-02-23 00:00 |
08:07:23.81 |
+31:31:22.0 |
HIP 39767 |
3.81 |
| 2026-02-23 12:00 |
08:07:19.95 |
+31:31:19.1 |
HIP 39767 |
4.58 |
| 2026-02-24 00:00 |
08:07:16.11 |
+31:31:16.0 |
HIP 39767 |
5.36 |