Barycentric velocity correction for TRAPPIST-1 from 2025 January to 2026 January. In our screening framework, sampled epochs between February and September do not satisfy the adopted 20° criterion. Over the retained epochs, the barycentric correction varies between approximately −30 and 0 km s⁻¹. The sinusoidal modulation reflects the projection of Earth’s nearly circular orbital velocity onto the line of sight to the star, producing a radial component with an amplitude of about ±30 km s⁻¹ and a 1 yr period, phase shifted according to the star’s ecliptic position. The right-hand y-axis shows the relative Doppler separation v_sys − v_bary(t), whose absolute value is maximized for TRAPPIST-1 at a barycentric velocity of 0.22 km s⁻¹ within this framework.