SpaceX has been pioneering reusable rockets for years, NASA is contemplating selling its soul to the highest bidder, and a Russian startup is building a nuclear engine for future rockets. But amid all these shakeups and innovations in the space sector, you might have missed the one Silicon Valley startup whose new technology should probably receive more attention.
Bloomberg Businessweek reports on Apollo Fusion, a new company designing a propulsion system for rocket engines that would use mercury as a fuel. Mercury has promise in this field, sure. But launching any rocket using this system would entail the risk of spreading a toxic substance through the atmosphere.
The idea of using mercury as a spacecraft fuel is not exactly new. NASA experimented with mercury in the ’60s, during the SERT missions. The two spacecraft in this series, SERT-I and SERT-II, were designed to test the concept of ion propulsion.
With an ion engine, powerful magnets in the spacecraft push away small charged particles at high speeds, generating thrust. Today’s ion engines commonly use krypton or xenon. For example, the recently deceased Dawn spacecraft used a xenon engine to zip from place to place in the asteroid belt. During the SERT test missions, however, the satellite engines used mercury.
Mercury is much heavier than either xenon or krypton, so spacecraft carrying them would be able to generate more thrust. Of course, mercury is also a dangerous neurotoxin, so NASA stopped using it after SERT.
Apollo Fusion is planning to bring mercury back, at least according to a collection of industry insiders talking to Bloomberg. If they’re successful, they could provide low-cost, high-power ion engines for satellites and spacecraft. But if they’re not, they could risk showering the atmosphere with toxic mercury.
For all our sakes, we just have to hope Apollo Fusion decides to pick a different fuel, or that it’s extremely careful during launches. If they’re not, we could all suffer the consequences.
Originally posted on Popular Mechanics