| Parameter |
Value |
| Designation |
C/2005 EL173 (LONEOS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2007-03-05T21:31:08.184000Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:47Z |
| Obs used |
314 |
| NEO |
- |
| M1 |
7.700 |
| K1 |
9.250 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2006-07-01.0000000 |
| e |
1.00318367 |
| q (au) |
3.886323 |
| a (au) |
-1220.704650 |
| i (deg) |
130.676676 |
| Ω (om, deg) |
344.789896 |
| ω (w, deg) |
261.492565 |
| M (ma, deg) |
-0.005729 |
Magnitude
Scatter + Global Linear
$$
M_a = (5.147 + 4.894\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
5.147 |
| n |
4.894 |
| gf |
0.860 |
| gb |
-0.523 |
| k |
0.981 |
| δ90 |
1.001 |
| 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 |
20:33:04.68 |
+13:53:12.0 |
HIP 101390 |
5.70 |
| 2026-05-12 12:00 |
20:33:03.63 |
+13:53:36.0 |
HIP 101390 |
5.23 |
| 2026-05-13 00:00 |
20:33:02.56 |
+13:53:59.8 |
HIP 101390 |
4.75 |
| 2026-05-13 12:00 |
20:33:01.46 |
+13:54:23.4 |
HIP 101390 |
4.28 |
| 2026-05-14 00:00 |
20:33:00.33 |
+13:54:47.0 |
HIP 101390 |
3.80 |
| 2026-05-14 12:00 |
20:32:59.18 |
+13:55:10.4 |
HIP 101390 |
3.33 |
| 2026-05-15 00:00 |
20:32:58.00 |
+13:55:33.6 |
HIP 101390 |
2.86 |
| 2026-05-15 12:00 |
20:32:56.80 |
+13:55:56.7 |
HIP 101390 |
2.39 |
| 2026-05-16 00:00 |
20:32:55.56 |
+13:56:19.7 |
HIP 101390 |
1.92 |
| 2026-05-16 12:00 |
20:32:54.31 |
+13:56:42.5 |
HIP 101390 |
1.47 |
| 2026-05-17 00:00 |
20:32:53.02 |
+13:57:05.2 |
HIP 101390 |
1.07 |
| 2026-05-17 12:00 |
20:32:51.71 |
+13:57:27.7 |
HIP 101390 |
0.76 |
| 2026-05-18 00:00 |
20:32:50.37 |
+13:57:50.1 |
HIP 101390 |
0.72 |
| 2026-05-18 12:00 |
20:32:49.01 |
+13:58:12.3 |
HIP 101390 |
0.98 |
| 2026-05-19 00:00 |
20:32:47.62 |
+13:58:34.4 |
HIP 101390 |
1.38 |
| 2026-05-19 12:00 |
20:32:46.21 |
+13:58:56.3 |
HIP 101390 |
1.84 |
| 2026-05-20 00:00 |
20:32:44.77 |
+13:59:18.1 |
HIP 101390 |
2.32 |
| 2026-05-20 12:00 |
20:32:43.30 |
+13:59:39.7 |
HIP 101390 |
2.81 |
| 2026-05-21 00:00 |
20:32:41.81 |
+14:00:01.1 |
HIP 101390 |
3.30 |
| 2026-05-21 12:00 |
20:32:40.30 |
+14:00:22.4 |
HIP 101390 |
3.81 |
| 2026-05-22 00:00 |
20:32:38.76 |
+14:00:43.5 |
HIP 101390 |
4.32 |
| 2026-05-22 12:00 |
20:32:37.19 |
+14:01:04.4 |
HIP 101390 |
4.83 |
| 2026-05-23 00:00 |
20:32:35.60 |
+14:01:25.2 |
HIP 101390 |
5.35 |
| 2026-05-23 12:00 |
20:32:33.98 |
+14:01:45.8 |
HIP 101390 |
5.87 |
| 2026-05-24 00:00 |
20:32:32.34 |
+14:02:06.3 |
HIP 101390 |
6.39 |
| 2026-05-24 12:00 |
20:32:30.68 |
+14:02:26.5 |
HIP 101390 |
6.92 |
| 2026-05-25 00:00 |
20:32:28.99 |
+14:02:46.6 |
HIP 101390 |
7.45 |
| 2026-05-25 12:00 |
20:32:27.27 |
+14:03:06.6 |
HIP 101390 |
7.98 |
| 2026-05-26 00:00 |
20:32:25.53 |
+14:03:26.3 |
HIP 101390 |
8.52 |
| 2026-05-26 12:00 |
20:32:23.77 |
+14:03:45.9 |
HIP 101390 |
9.05 |
| 2026-05-27 00:00 |
20:32:21.98 |
+14:04:05.3 |
HIP 101390 |
9.59 |
| 2026-05-27 12:00 |
20:32:20.17 |
+14:04:24.5 |
HIP 101390 |
10.14 |
| 2026-05-28 00:00 |
20:32:18.34 |
+14:04:43.6 |
HIP 101390 |
10.68 |
| 2026-05-28 12:00 |
20:32:16.48 |
+14:05:02.4 |
HIP 101390 |
11.23 |
| 2026-05-29 00:00 |
20:32:14.60 |
+14:05:21.1 |
HIP 101305 |
11.54 |
| 2026-05-29 12:00 |
20:32:12.69 |
+14:05:39.6 |
HIP 101305 |
11.12 |
| 2026-05-30 00:00 |
20:32:10.76 |
+14:05:57.9 |
HIP 101305 |
10.72 |
| 2026-05-30 12:00 |
20:32:08.81 |
+14:06:16.1 |
HIP 101305 |
10.34 |
| 2026-05-31 00:00 |
20:32:06.83 |
+14:06:34.0 |
HIP 101305 |
9.97 |
| 2026-05-31 12:00 |
20:32:04.84 |
+14:06:51.8 |
HIP 101305 |
9.63 |
| 2026-06-01 00:00 |
20:32:02.81 |
+14:07:09.3 |
HIP 101305 |
9.31 |
| 2026-06-01 12:00 |
20:32:00.77 |
+14:07:26.7 |
HIP 101305 |
9.02 |
| 2026-06-02 00:00 |
20:31:58.70 |
+14:07:43.9 |
HIP 101305 |
8.77 |