Atlas2,565 of 3,942

Figure-8 satellite HS.515

From Hristov, Hristova & Tanikawa (2026)

Figure-8 satellite HS.515 is a periodic orbit of the planar three-body problem: three equal masses that return to their starting positions and velocities every 362.81 time units, published by Hristov, Hristova & Tanikawa (2026). Stable orbits found by an exhaustive search of the figure-eight’s neighbourhood: each traces the eight with extra loops and twists, and every one is linearly stable to 40 digits. It is linearly stable (largest Floquet multiplier 1.000), so a small nudge only makes it wobble. The bodies pass within 0.451 of each other at a top speed of 1.56, line up 390 times a period, and the computed loop closes to 1.9×10⁻²⁸.

Measured over one period

Period: 362.8102074
Masses: 1 : 1 : 1
Energy: -1.39914
Angular momentum: 0
Closest approach: 0.4512
Top speed: 1.558
Path length: 988.25
Alignments per period: 390
Topology: (abAB)⁶⁵ (free-group class)
Stability: stable (|λ|max 1.000, published)
Loop closure: 1.9×10⁻²⁸

Neighbours on the map

All Figure-8 satellites, the families of periodic three-body orbits, or the atlas map.