The CIDMA Young Doctor Award is a prize for a researcher within 5 years after the PhD, who has made important contributions to his or her research field. The 2018 award is granted to Gr@v member Tjarda Boekholt for his recent achievements in the field of dynamical chaos in astronomical systems. During the annual meeting of CIDMA 2018, Tjarda presented his new numerical N-body code and the ability to obtain reversible solutions to highly chaotic systems. At the award ceremony, Tjarda presented his contribution to understanding the dynamics of Halley's Comet, including the unexpected importance of gravitational perturbations by planet Venus. "It is a great honour to win this CIDMA prize, which gives a great boost to young researchers" Tjarda says. In the Gr@v group, which is part of CIDMA and based at the University of Aveiro, Tjarda continues to study the dynamics of planetary and stellar systems.