| Parameter |
Value |
| Designation |
493P/LONEOS |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2026-01-26T13:20:25.137600Z |
| Orbit solution date (soln_date, UTC) |
2026-04-30T15:12:28Z |
| Obs used |
1380 |
| NEO |
- |
| M1 |
6.600 |
| K1 |
14.250 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2005-09-30T09:07:51.744000Z |
| Discovery magnitude (MPC) |
19.10 N |
| Discovery observatory (MPC) |
699 · Lowell Observatory-LONEOS |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2018-02-23.0000000 |
| e |
0.46282244 |
| q (au) |
3.822606 |
| a (au) |
7.116094 |
| i (deg) |
24.052912 |
| Ω (om, deg) |
1.356422 |
| ω (w, deg) |
83.557732 |
| M (ma, deg) |
209.712297 |
Magnitude
Scatter + Global Linear
$$
M_a = (6.257 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
6.257 |
| n |
6.000 |
| gf |
0.875 |
| gb |
-0.500 |
| k |
0.934 |
| δ90 |
1.000 |
| 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 |
| 2024-08-02 |
2026-01-25 |
+6.5607 |
-4.022 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
06:15:52.49 |
+43:29:26.9 |
HIP 29870 |
32.90 |
| 2026-05-12 12:00 |
06:16:40.39 |
+43:27:36.0 |
HIP 29870 |
27.81 |
| 2026-05-13 00:00 |
06:17:28.34 |
+43:25:44.8 |
HIP 29870 |
24.95 |
| 2026-05-13 12:00 |
06:18:16.34 |
+43:23:53.4 |
HIP 29870 |
25.12 |
| 2026-05-14 00:00 |
06:19:04.38 |
+43:22:01.7 |
HIP 29870 |
28.28 |
| 2026-05-14 12:00 |
06:19:52.47 |
+43:20:09.7 |
HIP 30117 |
32.45 |
| 2026-05-15 00:00 |
06:20:40.60 |
+43:18:17.5 |
HIP 30368 |
27.73 |
| 2026-05-15 12:00 |
06:21:28.77 |
+43:16:25.1 |
HIP 30368 |
18.79 |
| 2026-05-16 00:00 |
06:22:16.98 |
+43:14:32.4 |
HIP 30368 |
9.89 |
| 2026-05-16 12:00 |
06:23:05.23 |
+43:12:39.4 |
HIP 30368 |
1.87 |
| 2026-05-17 00:00 |
06:23:53.52 |
+43:10:46.1 |
HIP 30466 |
5.32 |
| 2026-05-17 12:00 |
06:24:41.84 |
+43:08:52.6 |
HIP 30466 |
6.66 |
| 2026-05-18 00:00 |
06:25:30.21 |
+43:06:58.8 |
HIP 30466 |
14.94 |
| 2026-05-18 12:00 |
06:26:18.60 |
+43:05:04.8 |
HIP 30814 |
23.57 |
| 2026-05-19 00:00 |
06:27:07.03 |
+43:03:10.4 |
HIP 30814 |
14.73 |
| 2026-05-19 12:00 |
06:27:55.49 |
+43:01:15.8 |
HIP 30814 |
6.50 |
| 2026-05-20 00:00 |
06:28:43.98 |
+42:59:20.9 |
HIP 30814 |
5.62 |
| 2026-05-20 12:00 |
06:29:32.50 |
+42:57:25.7 |
HIP 30814 |
13.62 |
| 2026-05-21 00:00 |
06:30:21.05 |
+42:55:30.2 |
HIP 30814 |
22.46 |
| 2026-05-21 12:00 |
06:31:09.63 |
+42:53:34.4 |
HIP 31240 |
27.05 |
| 2026-05-22 00:00 |
06:31:58.23 |
+42:51:38.3 |
HIP 31240 |
22.01 |
| 2026-05-22 12:00 |
06:32:46.85 |
+42:49:42.0 |
HIP 31240 |
20.06 |
| 2026-05-23 00:00 |
06:33:35.50 |
+42:47:45.3 |
HIP 31307 |
19.19 |
| 2026-05-23 12:00 |
06:34:24.18 |
+42:45:48.3 |
HIP 31379 |
16.04 |
| 2026-05-24 00:00 |
06:35:12.87 |
+42:43:51.0 |
HIP 31379 |
14.59 |
| 2026-05-24 12:00 |
06:36:01.59 |
+42:41:53.4 |
HIP 31379 |
18.36 |
| 2026-05-25 00:00 |
06:36:50.32 |
+42:39:55.5 |
HIP 31379 |
25.09 |
| 2026-05-25 12:00 |
06:37:39.08 |
+42:37:57.3 |
HIP 31832 |
20.45 |
| 2026-05-26 00:00 |
06:38:27.85 |
+42:35:58.8 |
HIP 31832 |
11.65 |
| 2026-05-26 12:00 |
06:39:16.64 |
+42:33:59.9 |
HIP 31832 |
4.69 |
| 2026-05-27 00:00 |
06:40:05.44 |
+42:32:00.7 |
HIP 31893 |
2.05 |
| 2026-05-27 12:00 |
06:40:54.26 |
+42:30:01.2 |
HIP 31893 |
10.48 |
| 2026-05-28 00:00 |
06:41:43.09 |
+42:28:01.4 |
HIP 31893 |
19.63 |
| 2026-05-28 12:00 |
06:42:31.94 |
+42:26:01.2 |
HIP 32092 |
25.06 |
| 2026-05-29 00:00 |
06:43:20.80 |
+42:24:00.7 |
HIP 32092 |
29.38 |
| 2026-05-29 12:00 |
06:44:09.67 |
+42:21:59.9 |
HIP 32433 |
23.29 |
| 2026-05-30 00:00 |
06:44:58.55 |
+42:19:58.7 |
HIP 32433 |
14.05 |
| 2026-05-30 12:00 |
06:45:47.44 |
+42:17:57.2 |
HIP 32433 |
4.85 |
| 2026-05-31 00:00 |
06:46:36.34 |
+42:15:55.4 |
HIP 32433 |
4.63 |
| 2026-05-31 12:00 |
06:47:25.25 |
+42:13:53.2 |
HIP 32493 |
13.14 |
| 2026-06-01 00:00 |
06:48:14.17 |
+42:11:50.7 |
HIP 32493 |
18.01 |
| 2026-06-01 12:00 |
06:49:03.09 |
+42:09:47.8 |
HIP 32493 |
25.48 |
| 2026-06-02 00:00 |
06:49:52.02 |
+42:07:44.6 |
HIP 32844 |
23.14 |