4. SUMMARY
The key conclusions of our study are listed as follows:
1. With our followup astrometric observations, we confirmed that
2020 XL5 is a new Earth Trojan
after 2010 TK7.
2. 2020 XL5 is only a transient Earth Trojan, as it has been librating around the
L4 point only
since the 15th century, and its orbit is unstable on a ∼10 kyr timescale primarily due to
frequent
close approaches to Venus at mutual distances of .0.1 au.
3. The minima of its current effective potential are clearly shifted away from 60◦
to a larger angle
in the resonant argument because of its nontrivial
orbital inclination and eccentricity