Selam (pictured below) is the strange secondary of  the Dinkinesh binary asteroid system in the main-belt. Using the secular theory based on binary-Yarkovsky-O’Keefe-Radzievskii-Paddack (BYORP) and tides, we were able to constrain the age of this asteroid to 1-10 million years. Read up on the methods and results in the article in Astronomy & Astrophysics published here. As a part of this work, we derived some really interesting equations as well which include an improved tidal-BYORP equilibrium equation and a condition for YORP stability.

We Found the Dynamical Age of Selam