NASA has spent nine years and about $2 billion in its quest to drill and store samples of Martian rocks. The Perseverance rover was poised to finally make that happen for the first time on Friday. The rover picked a rock in an ancient Mars lake bed that could have once held alien life, and attempted to drill. But then something strange happened: The sample seems to have vanished without a trace.... ...To figure out what happened, NASA is instructing Perseverance to take close-up pictures of the bore hole it made. Mission controllers will then try to make plans for...