| Parameter |
Value |
| Designation |
493P/LONEOS |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2026-01-26T12:27:24.261120Z |
| Orbit solution date (soln_date, UTC) |
2026-05-28T12:12:27Z |
| Obs used |
1386 |
| NEO |
- |
| M1 |
6.500 |
| K1 |
14.500 |
| 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) |
2018-03-07.0000000 |
| e |
0.46281239 |
| q (au) |
3.822731 |
| a (au) |
7.116193 |
| i (deg) |
24.052948 |
| Ω (om, deg) |
1.355621 |
| ω (w, deg) |
83.556049 |
| M (ma, deg) |
210.340358 |
Magnitude
Scatter + Global Linear
$$
M_a = (5.253 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
5.253 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.501 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2024-08-02 |
2026-01-25 |
+6.1626 |
-3.722 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
08:20:30.51 |
+37:37:48.7 |
HIP 40718 |
22.26 |
| 2026-07-29 12:00 |
08:21:15.59 |
+37:35:12.2 |
HIP 40922 |
19.04 |
| 2026-07-30 00:00 |
08:22:00.62 |
+37:32:35.5 |
HIP 40922 |
19.58 |
| 2026-07-30 12:00 |
08:22:45.58 |
+37:29:58.8 |
HIP 40922 |
24.02 |
| 2026-07-31 00:00 |
08:23:30.47 |
+37:27:21.9 |
HIP 41286 |
22.85 |
| 2026-07-31 12:00 |
08:24:15.29 |
+37:24:45.0 |
HIP 41286 |
13.67 |
| 2026-08-01 00:00 |
08:25:00.05 |
+37:22:07.9 |
HIP 41286 |
4.85 |
| 2026-08-01 12:00 |
08:25:44.74 |
+37:19:30.7 |
HIP 41286 |
5.65 |
| 2026-08-02 00:00 |
08:26:29.37 |
+37:16:53.4 |
HIP 41286 |
14.54 |
| 2026-08-02 12:00 |
08:27:13.92 |
+37:14:16.0 |
HIP 41552 |
19.22 |
| 2026-08-03 00:00 |
08:27:58.41 |
+37:11:38.5 |
HIP 41552 |
11.92 |
| 2026-08-03 12:00 |
08:28:42.83 |
+37:09:00.9 |
HIP 41552 |
9.24 |
| 2026-08-04 00:00 |
08:29:27.18 |
+37:06:23.3 |
HIP 41691 |
6.19 |
| 2026-08-04 12:00 |
08:30:11.46 |
+37:03:45.5 |
HIP 41691 |
3.06 |
| 2026-08-05 00:00 |
08:30:55.67 |
+37:01:07.7 |
HIP 41691 |
12.25 |
| 2026-08-05 12:00 |
08:31:39.82 |
+36:58:29.9 |
HIP 41888 |
11.40 |
| 2026-08-06 00:00 |
08:32:23.89 |
+36:55:51.9 |
HIP 41888 |
3.31 |
| 2026-08-06 12:00 |
08:33:07.89 |
+36:53:14.0 |
HIP 41888 |
7.80 |
| 2026-08-07 00:00 |
08:33:51.82 |
+36:50:35.9 |
HIP 42006 |
16.21 |
| 2026-08-07 12:00 |
08:34:35.67 |
+36:47:57.8 |
HIP 42006 |
21.54 |
| 2026-08-08 00:00 |
08:35:19.46 |
+36:45:19.7 |
HIP 42090 |
21.37 |
| 2026-08-08 12:00 |
08:36:03.17 |
+36:42:41.5 |
HIP 42090 |
23.66 |
| 2026-08-09 00:00 |
08:36:46.81 |
+36:40:03.4 |
HIP 42364 |
27.89 |
| 2026-08-09 12:00 |
08:37:30.37 |
+36:37:25.2 |
HIP 42364 |
25.61 |
| 2026-08-10 00:00 |
08:38:13.86 |
+36:34:46.9 |
HIP 42364 |
26.45 |
| 2026-08-10 12:00 |
08:38:57.28 |
+36:32:08.7 |
HIP 42364 |
30.15 |
| 2026-08-11 00:00 |
08:39:40.62 |
+36:29:30.5 |
HIP 42616 |
25.27 |
| 2026-08-11 12:00 |
08:40:23.88 |
+36:26:52.3 |
HIP 42616 |
17.95 |
| 2026-08-12 00:00 |
08:41:07.06 |
+36:24:14.0 |
HIP 42616 |
13.11 |
| 2026-08-12 12:00 |
08:41:50.17 |
+36:21:35.8 |
HIP 42616 |
13.66 |
| 2026-08-13 00:00 |
08:42:33.20 |
+36:18:57.7 |
HIP 42864 |
18.97 |
| 2026-08-13 12:00 |
08:43:16.15 |
+36:16:19.5 |
HIP 42864 |
9.97 |
| 2026-08-14 00:00 |
08:43:59.03 |
+36:13:41.4 |
HIP 42864 |
1.64 |
| 2026-08-14 12:00 |
08:44:41.82 |
+36:11:03.3 |
HIP 42864 |
8.31 |
| 2026-08-15 00:00 |
08:45:24.53 |
+36:08:25.3 |
HIP 42864 |
17.26 |
| 2026-08-15 12:00 |
08:46:07.16 |
+36:05:47.3 |
HIP 43024 |
19.78 |
| 2026-08-16 00:00 |
08:46:49.71 |
+36:03:09.4 |
HIP 43024 |
19.66 |
| 2026-08-16 12:00 |
08:47:32.18 |
+36:00:31.5 |
HIP 43024 |
23.32 |
| 2026-08-17 00:00 |
08:48:14.56 |
+35:57:53.7 |
HIP 43024 |
29.37 |
| 2026-08-17 12:00 |
08:48:56.86 |
+35:55:16.0 |
HIP 43419 |
23.92 |
| 2026-08-18 00:00 |
08:49:39.08 |
+35:52:38.4 |
HIP 43419 |
15.41 |
| 2026-08-18 12:00 |
08:50:21.21 |
+35:50:00.8 |
HIP 43419 |
7.91 |
| 2026-08-19 00:00 |
08:51:03.26 |
+35:47:23.4 |
HIP 43419 |
6.90 |