Earth-based radar speckle displacement interferometry to solve the problem of Mercury's obliquity and wobble

Though Mercury at its inferior conjunctions with Earth is approximately as far from us as Mars is it remains nearly unknown until present. All the knowledge about this nearest to Sun planet is based mainly on the data of Mariner 10 flyby mission in 1974-75 and ground-based radar observations. One of central fundamental problems to be solved in the first place is the problem of Mercury's interior. Peale (1988) developed a methodology to determine the state and size of Mercury's core. It is expected that all the necessary input information for the methodology will be obtained while each of the two upcoming space missions: MESSENGER, USA and BepiColombo, Europe and Japan which will reach Mercury at the end of this and at the beginning of the next decade respectively. Until the data of these missions are available it is worth while to analyse at what extent Earth-based radar facilities may help in solving the problem of Mercury's interior.