C/2005 EL173 (LONEOS)
| 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) |
| 2026-02-03 00:00 |
20:28:44.96 |
+12:30:49.9 |
HIP 101055 |
11.59 |
| 2026-02-03 12:00 |
20:28:47.89 |
+12:31:05.2 |
HIP 101055 |
11.02 |
| 2026-02-04 00:00 |
20:28:50.81 |
+12:31:20.6 |
HIP 101055 |
10.48 |
| 2026-02-04 12:00 |
20:28:53.73 |
+12:31:36.2 |
HIP 101055 |
9.96 |
| 2026-02-05 00:00 |
20:28:56.65 |
+12:31:52.0 |
HIP 101055 |
9.47 |
| 2026-02-05 12:00 |
20:28:59.56 |
+12:32:08.0 |
HIP 101055 |
9.01 |
| 2026-02-06 00:00 |
20:29:02.46 |
+12:32:24.2 |
HIP 101055 |
8.60 |
| 2026-02-06 12:00 |
20:29:05.36 |
+12:32:40.6 |
HIP 101055 |
8.23 |
| 2026-02-07 00:00 |
20:29:08.25 |
+12:32:57.1 |
HIP 101055 |
7.91 |
| 2026-02-07 12:00 |
20:29:11.14 |
+12:33:13.9 |
HIP 101055 |
7.65 |
| 2026-02-08 00:00 |
20:29:14.02 |
+12:33:30.9 |
HIP 101055 |
7.46 |
| 2026-02-08 12:00 |
20:29:16.89 |
+12:33:48.0 |
HIP 101055 |
7.33 |
| 2026-02-09 00:00 |
20:29:19.75 |
+12:34:05.4 |
HIP 101055 |
7.28 |
| 2026-02-09 12:00 |
20:29:22.61 |
+12:34:22.9 |
HIP 101055 |
7.31 |
| 2026-02-10 00:00 |
20:29:25.46 |
+12:34:40.7 |
HIP 101055 |
7.41 |
| 2026-02-10 12:00 |
20:29:28.31 |
+12:34:58.6 |
HIP 101055 |
7.58 |
| 2026-02-11 00:00 |
20:29:31.15 |
+12:35:16.7 |
HIP 101055 |
7.81 |
| 2026-02-11 12:00 |
20:29:33.97 |
+12:35:34.9 |
HIP 101055 |
8.11 |
| 2026-02-12 00:00 |
20:29:36.79 |
+12:35:53.4 |
HIP 101055 |
8.46 |
| 2026-02-12 12:00 |
20:29:39.61 |
+12:36:12.0 |
HIP 101055 |
8.85 |
| 2026-02-13 00:00 |
20:29:42.41 |
+12:36:30.9 |
HIP 101055 |
9.29 |
| 2026-02-13 12:00 |
20:29:45.20 |
+12:36:49.9 |
HIP 101055 |
9.76 |
| 2026-02-14 00:00 |
20:29:47.99 |
+12:37:09.0 |
HIP 101055 |
10.26 |
| 2026-02-14 12:00 |
20:29:50.76 |
+12:37:28.4 |
HIP 101055 |
10.79 |
| 2026-02-15 00:00 |
20:29:53.53 |
+12:37:47.9 |
HIP 101055 |
11.34 |
| 2026-02-15 12:00 |
20:29:56.29 |
+12:38:07.6 |
HIP 101055 |
11.91 |
| 2026-02-16 00:00 |
20:29:59.03 |
+12:38:27.5 |
HIP 101055 |
12.50 |
| 2026-02-16 12:00 |
20:30:01.77 |
+12:38:47.6 |
HIP 101055 |
13.09 |
| 2026-02-17 00:00 |
20:30:04.49 |
+12:39:07.8 |
HIP 101055 |
13.70 |
| 2026-02-17 12:00 |
20:30:07.21 |
+12:39:28.2 |
HIP 101055 |
14.32 |
| 2026-02-18 00:00 |
20:30:09.91 |
+12:39:48.7 |
HIP 101055 |
14.95 |
| 2026-02-18 12:00 |
20:30:12.60 |
+12:40:09.4 |
HIP 101055 |
15.59 |
| 2026-02-19 00:00 |
20:30:15.29 |
+12:40:30.3 |
HIP 101055 |
16.23 |
| 2026-02-19 12:00 |
20:30:17.96 |
+12:40:51.3 |
HIP 101055 |
16.88 |
| 2026-02-20 00:00 |
20:30:20.61 |
+12:41:12.6 |
HIP 101055 |
17.53 |
| 2026-02-20 12:00 |
20:30:23.26 |
+12:41:33.9 |
HIP 101055 |
18.18 |
| 2026-02-21 00:00 |
20:30:25.89 |
+12:41:55.4 |
HIP 101055 |
18.84 |
| 2026-02-21 12:00 |
20:30:28.51 |
+12:42:17.1 |
HIP 101055 |
19.50 |
| 2026-02-22 00:00 |
20:30:31.12 |
+12:42:38.9 |
HIP 101055 |
20.17 |
| 2026-02-22 12:00 |
20:30:33.72 |
+12:43:00.9 |
HIP 101055 |
20.83 |
| 2026-02-23 00:00 |
20:30:36.30 |
+12:43:23.1 |
HIP 101055 |
21.50 |
| 2026-02-23 12:00 |
20:30:38.87 |
+12:43:45.3 |
HIP 101055 |
22.17 |
| 2026-02-24 00:00 |
20:30:41.43 |
+12:44:07.8 |
HIP 101055 |
22.83 |