493P/LONEOS

Metadata

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

493P/LONEOS · Magnitude (Full range)

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)
2026-06-01 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
2026-06-02 12:00 06:50:40.96 +42:05:41.0 HIP 32844 18.81
2026-06-03 00:00 06:51:29.90 +42:03:37.1 HIP 33050 17.89
2026-06-03 12:00 06:52:18.85 +42:01:32.8 HIP 33050 8.71
2026-06-04 00:00 06:53:07.80 +41:59:28.2 HIP 33050 2.30
2026-06-04 12:00 06:53:56.75 +41:57:23.3 HIP 33050 10.43
2026-06-05 00:00 06:54:45.70 +41:55:17.9 HIP 33304 12.14
2026-06-05 12:00 06:55:34.65 +41:53:12.3 HIP 33304 9.43
2026-06-06 00:00 06:56:23.61 +41:51:06.2 HIP 33433 10.82
2026-06-06 12:00 06:57:12.57 +41:48:59.8 HIP 33433 9.08
2026-06-07 00:00 06:58:01.52 +41:46:53.1 HIP 33507 4.76
2026-06-07 12:00 06:58:50.47 +41:44:46.0 HIP 33507 10.81
2026-06-08 00:00 06:59:39.43 +41:42:38.5 HIP 33507 19.68
2026-06-08 12:00 07:00:28.37 +41:40:30.7 HIP 33936 23.25
2026-06-09 00:00 07:01:17.32 +41:38:22.5 HIP 33936 13.99
2026-06-09 12:00 07:02:06.26 +41:36:14.0 HIP 33936 5.21
2026-06-10 00:00 07:02:55.20 +41:34:05.1 HIP 33936 5.91
2026-06-10 12:00 07:03:44.13 +41:31:55.8 HIP 34120 9.98
2026-06-11 00:00 07:04:33.05 +41:29:46.2 HIP 34120 7.28
2026-06-11 12:00 07:05:21.97 +41:27:36.2 HIP 34120 13.54
2026-06-12 00:00 07:06:10.88 +41:25:25.9 HIP 34315 10.25
2026-06-12 12:00 07:06:59.78 +41:23:15.2 HIP 34315 4.90
2026-06-13 00:00 07:07:48.67 +41:21:04.1 HIP 34403 5.80
2026-06-13 12:00 07:08:37.55 +41:18:52.7 HIP 34403 8.21
2026-06-14 00:00 07:09:26.42 +41:16:41.0 HIP 34403 16.72
2026-06-14 12:00 07:10:15.27 +41:14:28.8 HIP 34403 25.88
2026-06-15 00:00 07:11:04.12 +41:12:16.4 HIP 34743 26.31
2026-06-15 12:00 07:11:52.95 +41:10:03.5 HIP 34787 23.44
2026-06-16 00:00 07:12:41.76 +41:07:50.4 HIP 34988 19.18
2026-06-16 12:00 07:13:30.56 +41:05:36.8 HIP 34988 11.72
2026-06-17 00:00 07:14:19.34 +41:03:23.0 HIP 34988 9.23
2026-06-17 12:00 07:15:08.10 +41:01:08.8 HIP 34988 14.55
2026-06-18 00:00 07:15:56.85 +40:58:54.2 HIP 35314 19.71
2026-06-18 12:00 07:16:45.57 +40:56:39.3 HIP 35314 10.39
2026-06-19 00:00 07:17:34.28 +40:54:24.0 HIP 35314 2.60
2026-06-19 12:00 07:18:22.96 +40:52:08.4 HIP 35341 4.01
2026-06-20 00:00 07:19:11.62 +40:49:52.4 HIP 35527 10.83
2026-06-20 12:00 07:20:00.26 +40:47:36.2 HIP 35527 4.60
2026-06-21 00:00 07:20:48.88 +40:45:19.5 HIP 35527 10.25
2026-06-21 12:00 07:21:37.47 +40:43:02.5 HIP 35811 17.29
2026-06-22 00:00 07:22:26.03 +40:40:45.2 HIP 35811 8.15