In the recent years, Russian government and scientific society have been coming gradually to an understanding the way of development science in Russia. Government have accepted a program of building six mega-science projects, and one of them can be a new fourth generation x-ray light source based on accelerator-recuperator. Multiturn energy recovery linacs (ERL) looks very promising for making modern synchrotron radiation sources, being less expensive and more flexible. At this time only one multiturn ERL exists. This Novosibirsk ERL operates with two orbits and two free electron lasers based on one linac now. The conception of Multiturn Accelerator-recuperator Radiation Source (MARS) was proposed in 1997 by G.N. Kulipanov, A.N. Skrinsky and N.A. Vinokurov. The use of the ERL with two separated accelerating structures allows to exclude main disadvantages of scheme with one linac, such as the pass of electron bunches with different energies through the same magnetic arcs. The feasibility study for such ERLbased high brightness x-ray source is presented.