| Parameter |
Value |
| Designation |
C/2007 K5 (Lovejoy) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2007-05-01T23:02:06.720000Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:09Z |
| Obs used |
48 |
| NEO |
- |
| M1 |
12.000 |
| K1 |
10.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2007-06-15.0000000 |
| e |
0.97669348 |
| q (au) |
1.149171 |
| a (au) |
49.306854 |
| i (deg) |
64.883215 |
| Ω (om, deg) |
193.738734 |
| ω (w, deg) |
255.585000 |
| M (ma, deg) |
0.125370 |
Magnitude
Scatter + Global Linear
$$
M_a = (13.220 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
13.220 |
| n |
6.000 |
| 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) |
| 2026-05-12 00:00 |
16:05:21.56 |
+32:46:12.6 |
HIP 78729 |
20.93 |
| 2026-05-12 12:00 |
16:05:17.88 |
+32:46:28.1 |
HIP 78729 |
20.66 |
| 2026-05-13 00:00 |
16:05:14.20 |
+32:46:43.2 |
HIP 78729 |
20.42 |
| 2026-05-13 12:00 |
16:05:10.51 |
+32:46:58.1 |
HIP 78729 |
20.20 |
| 2026-05-14 00:00 |
16:05:06.81 |
+32:47:12.5 |
HIP 78729 |
20.01 |
| 2026-05-14 12:00 |
16:05:03.11 |
+32:47:26.7 |
HIP 78729 |
19.84 |
| 2026-05-15 00:00 |
16:04:59.41 |
+32:47:40.5 |
HIP 78729 |
19.70 |
| 2026-05-15 12:00 |
16:04:55.69 |
+32:47:54.0 |
HIP 78729 |
19.59 |
| 2026-05-16 00:00 |
16:04:51.97 |
+32:48:07.1 |
HIP 78729 |
19.50 |
| 2026-05-16 12:00 |
16:04:48.25 |
+32:48:19.8 |
HIP 78729 |
19.45 |
| 2026-05-17 00:00 |
16:04:44.52 |
+32:48:32.3 |
HIP 78729 |
19.42 |
| 2026-05-17 12:00 |
16:04:40.79 |
+32:48:44.4 |
HIP 78729 |
19.41 |
| 2026-05-18 00:00 |
16:04:37.06 |
+32:48:56.1 |
HIP 78729 |
19.44 |
| 2026-05-18 12:00 |
16:04:33.32 |
+32:49:07.5 |
HIP 78729 |
19.50 |
| 2026-05-19 00:00 |
16:04:29.58 |
+32:49:18.5 |
HIP 78729 |
19.58 |
| 2026-05-19 12:00 |
16:04:25.83 |
+32:49:29.2 |
HIP 78729 |
19.69 |
| 2026-05-20 00:00 |
16:04:22.08 |
+32:49:39.6 |
HIP 78729 |
19.82 |
| 2026-05-20 12:00 |
16:04:18.33 |
+32:49:49.6 |
HIP 78729 |
19.99 |
| 2026-05-21 00:00 |
16:04:14.58 |
+32:49:59.2 |
HIP 78729 |
20.17 |
| 2026-05-21 12:00 |
16:04:10.83 |
+32:50:08.5 |
HIP 78729 |
20.38 |
| 2026-05-22 00:00 |
16:04:07.08 |
+32:50:17.5 |
HIP 78729 |
20.62 |
| 2026-05-22 12:00 |
16:04:03.32 |
+32:50:26.1 |
HIP 78729 |
20.88 |
| 2026-05-23 00:00 |
16:03:59.56 |
+32:50:34.3 |
HIP 78729 |
21.15 |
| 2026-05-23 12:00 |
16:03:55.81 |
+32:50:42.2 |
HIP 78729 |
21.45 |
| 2026-05-24 00:00 |
16:03:52.05 |
+32:50:49.7 |
HIP 78729 |
21.77 |
| 2026-05-24 12:00 |
16:03:48.30 |
+32:50:56.9 |
HIP 78729 |
22.11 |
| 2026-05-25 00:00 |
16:03:44.54 |
+32:51:03.8 |
HIP 78576 |
22.15 |
| 2026-05-25 12:00 |
16:03:40.79 |
+32:51:10.3 |
HIP 78576 |
21.79 |
| 2026-05-26 00:00 |
16:03:37.04 |
+32:51:16.4 |
HIP 78576 |
21.44 |
| 2026-05-26 12:00 |
16:03:33.28 |
+32:51:22.2 |
HIP 78576 |
21.11 |
| 2026-05-27 00:00 |
16:03:29.53 |
+32:51:27.7 |
HIP 78576 |
20.80 |
| 2026-05-27 12:00 |
16:03:25.79 |
+32:51:32.8 |
HIP 78576 |
20.52 |
| 2026-05-28 00:00 |
16:03:22.04 |
+32:51:37.5 |
HIP 78576 |
20.25 |
| 2026-05-28 12:00 |
16:03:18.30 |
+32:51:41.9 |
HIP 78576 |
20.01 |
| 2026-05-29 00:00 |
16:03:14.56 |
+32:51:45.9 |
HIP 78576 |
19.79 |
| 2026-05-29 12:00 |
16:03:10.82 |
+32:51:49.6 |
HIP 78576 |
19.59 |
| 2026-05-30 00:00 |
16:03:07.09 |
+32:51:53.0 |
HIP 78576 |
19.42 |
| 2026-05-30 12:00 |
16:03:03.36 |
+32:51:55.9 |
HIP 78576 |
19.28 |
| 2026-05-31 00:00 |
16:02:59.64 |
+32:51:58.6 |
HIP 78576 |
19.16 |
| 2026-05-31 12:00 |
16:02:55.92 |
+32:52:00.9 |
HIP 78576 |
19.06 |
| 2026-06-01 00:00 |
16:02:52.20 |
+32:52:02.8 |
HIP 78576 |
19.00 |
| 2026-06-01 12:00 |
16:02:48.49 |
+32:52:04.4 |
HIP 78576 |
18.95 |
| 2026-06-02 00:00 |
16:02:44.78 |
+32:52:05.6 |
HIP 78576 |
18.94 |