16192

We propose to closely follow the expected re-activation of the unusual binary main-belt comet 288P (300163) in the fall of 2021 comma to identify the active component(s). This is a crucial parameter to understand the formation and evolution of this system which is unique among the known binary asteroids both because of its comet-like activity and because of its wide comma eccentric and asynchronous mutual orbit in combination with similarly sized components. We request a total of 8 orbits. Seven orbits comma distributed across one month comma will serve to measure the brightness increase due to dust as the system re-approaches perihelion in 2021. In addition comma we request 1 orbit in 2021 June to probe for a potential orbit instability. It is currently unclear why no other systems with similar orbital properties as 288P are known. There is a strong detection bias against such systems comma and the binary nature of 288P was only identified because of its activity. One the other hand comma if activity is needed to form such systems comma they may indeed be rare. Our proposed observations will shed light on the frequency of similar systems and on the processes behind binary asteroid formation and evolution. Since the re-activation is expected for the 2021 September-October time frame comma we request 4 orbits in Cycle 28 and 4 orbits in Cycle 29.