| Parameter |
Value |
| Designation |
201P/LONEOS |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2015-01-14T08:01:42.346560Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:27:52Z |
| Obs used |
865 |
| NEO |
- |
| M1 |
13.000 |
| K1 |
15.250 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2012-05-08.0000000 |
| e |
0.61286098 |
| q (au) |
1.339984 |
| a (au) |
3.461247 |
| i (deg) |
7.036519 |
| Ω (om, deg) |
35.285668 |
| ω (w, deg) |
24.953960 |
| M (ma, deg) |
209.799179 |
Magnitude
Scatter + Global Linear
$$
M_a = (14.450 + 5.551\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
14.450 |
| n |
5.551 |
| gf |
1.000 |
| gb |
-0.662 |
| k |
0.800 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2014-07-08 |
2014-10-02 |
+4.5177 |
-1.113 |
| 2014-10-02 |
2015-01-13 |
-5.8786 |
+1.035 |
| 2015-01-16 |
2015-04-16 |
+15.3215 |
-2.697 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
19:32:14.59 |
-27:12:32.4 |
HIP 96263 |
29.17 |
| 2026-03-26 12:00 |
19:32:35.72 |
-27:12:25.1 |
HIP 96263 |
24.50 |
| 2026-03-27 00:00 |
19:32:56.69 |
-27:12:18.1 |
HIP 96263 |
19.87 |
| 2026-03-27 12:00 |
19:33:17.51 |
-27:12:11.6 |
HIP 96263 |
15.29 |
| 2026-03-28 00:00 |
19:33:38.16 |
-27:12:05.4 |
HIP 96263 |
10.80 |
| 2026-03-28 12:00 |
19:33:58.66 |
-27:11:59.7 |
HIP 96263 |
6.49 |
| 2026-03-29 00:00 |
19:34:18.99 |
-27:11:54.4 |
HIP 96263 |
3.06 |
| 2026-03-29 12:00 |
19:34:39.16 |
-27:11:49.5 |
HIP 96273 |
2.57 |
| 2026-03-30 00:00 |
19:34:59.17 |
-27:11:45.1 |
HIP 96273 |
6.13 |
| 2026-03-30 12:00 |
19:35:19.02 |
-27:11:41.0 |
HIP 96273 |
10.37 |
| 2026-03-31 00:00 |
19:35:38.70 |
-27:11:37.5 |
HIP 96273 |
14.67 |
| 2026-03-31 12:00 |
19:35:58.21 |
-27:11:34.3 |
HIP 96273 |
18.97 |
| 2026-04-01 00:00 |
19:36:17.55 |
-27:11:31.6 |
HIP 96332 |
21.80 |
| 2026-04-01 12:00 |
19:36:36.72 |
-27:11:29.4 |
HIP 96332 |
25.00 |
| 2026-04-02 00:00 |
19:36:55.73 |
-27:11:27.7 |
HIP 96332 |
28.43 |
| 2026-04-02 12:00 |
19:37:14.56 |
-27:11:26.4 |
HIP 96645 |
25.11 |
| 2026-04-03 00:00 |
19:37:33.21 |
-27:11:25.6 |
HIP 96645 |
21.45 |
| 2026-04-03 12:00 |
19:37:51.70 |
-27:11:25.3 |
HIP 96645 |
18.03 |
| 2026-04-04 00:00 |
19:38:10.00 |
-27:11:25.5 |
HIP 96645 |
14.98 |
| 2026-04-04 12:00 |
19:38:28.13 |
-27:11:26.2 |
HIP 96645 |
12.54 |
| 2026-04-05 00:00 |
19:38:46.08 |
-27:11:27.4 |
HIP 96645 |
11.07 |
| 2026-04-05 12:00 |
19:39:03.85 |
-27:11:29.1 |
HIP 96645 |
10.92 |
| 2026-04-06 00:00 |
19:39:21.43 |
-27:11:31.4 |
HIP 96645 |
12.11 |
| 2026-04-06 12:00 |
19:39:38.84 |
-27:11:34.2 |
HIP 96645 |
14.27 |
| 2026-04-07 00:00 |
19:39:56.05 |
-27:11:37.5 |
HIP 96645 |
17.00 |
| 2026-04-07 12:00 |
19:40:13.09 |
-27:11:41.3 |
HIP 96645 |
20.05 |
| 2026-04-08 00:00 |
19:40:29.93 |
-27:11:45.7 |
HIP 96645 |
23.28 |
| 2026-04-08 12:00 |
19:40:46.58 |
-27:11:50.7 |
HIP 96645 |
26.60 |
| 2026-04-09 00:00 |
19:41:03.05 |
-27:11:56.2 |
HIP 96823 |
29.96 |
| 2026-04-09 12:00 |
19:41:19.32 |
-27:12:02.3 |
HIP 96823 |
30.45 |
| 2026-04-10 00:00 |
19:41:35.39 |
-27:12:09.0 |
HIP 96823 |
31.33 |
| 2026-04-10 12:00 |
19:41:51.27 |
-27:12:16.2 |
HIP 96823 |
32.55 |
| 2026-04-11 00:00 |
19:42:06.96 |
-27:12:24.0 |
HIP 96823 |
34.06 |
| 2026-04-11 12:00 |
19:42:22.44 |
-27:12:32.5 |
HIP 97125 |
31.18 |
| 2026-04-12 00:00 |
19:42:37.72 |
-27:12:41.5 |
HIP 97125 |
28.37 |
| 2026-04-12 12:00 |
19:42:52.80 |
-27:12:51.2 |
HIP 97125 |
25.75 |
| 2026-04-13 00:00 |
19:43:07.68 |
-27:13:01.5 |
HIP 97125 |
23.35 |
| 2026-04-13 12:00 |
19:43:22.35 |
-27:13:12.4 |
HIP 97125 |
21.24 |
| 2026-04-14 00:00 |
19:43:36.82 |
-27:13:23.9 |
HIP 97125 |
19.49 |
| 2026-04-14 12:00 |
19:43:51.07 |
-27:13:36.1 |
HIP 97125 |
18.18 |
| 2026-04-15 00:00 |
19:44:05.12 |
-27:13:48.9 |
HIP 97125 |
17.38 |
| 2026-04-15 12:00 |
19:44:18.95 |
-27:14:02.3 |
HIP 97195 |
15.79 |
| 2026-04-16 00:00 |
19:44:32.57 |
-27:14:16.4 |
HIP 97195 |
13.37 |