Opportunity and Curiosity, will be protected by the thin Martian atmosphere, which should be sufficiently dense to destroy any incoming bits. To protect the orbiting Martian fleet, NASA’s Mars Odyssey, Mars Reconnaissance Orbiter, newly arrived Maven and Mars Orbiter Mission (India) and ESA’s Mars Express have changed their orbits so they can be on the opposite side of Mars when Siding Spring is at closest point of approach.