The flashing of a nearby star has drawn MIT astronomers to a new and mysterious system 3,000 light years from Earth. The stellar oddity appears to be a new “black widow binary” — a rapidly spinning neutron star, or pulsar, that is circling and slowly consuming a smaller companion star, as its arachnid namesake does to its mate. Astronomers know of about two dozen black widow binaries in the Milky Way. This newest candidate, named ZTF J1406+1222, has the shortest orbital period yet identified, with the pulsar and companion star…