https://phys.org/news/2018-11-mars-minutes-month.html > After micromanaging every step of the way, flight controllers will be powerless over what happens at the end of the road Monday, nearly 100 million miles (160 million kilometers) away. The communication lag between Mars and Earth is eight minutes. > "By the time we hear anything, the whole thing is already done," said project manager Tom Hoffman of NASA's Jet Propulsion Laboratory. "Either it happened or it hasn't happened."