Two space tech companies, Helios and Eta Space, today announce they are joining forces to solve the problem of oxygen in space. If humanity is to have a sustainable presence beyond Earth, the reusable methane-fueled rocket systems need liquid oxygen at a ratio of 1:4, so the only cost-effective solution to refueling in orbit is to create and store oxygen on the Moon and on Mars. Helios, which is backed by the Israel Space Agency (ISA) and...