Color and black - and - white images of Earth taken by two NASA interplanetary spacecraft on July 19 show our planet and its moon as bright beacons from millions of miles away in space. (sciencedaily.com)
Developing a long - lived rover that could explore Venus's surface is a greater challenge — the circuitry in current interplanetary spacecraft would quickly fry there. (discovermagazine.com)
In fact, thanks to radar beams pinging off various solar - system bodies and to tracking of interplanetary spacecraft, the sun - Earth distance has been pegged with remarkable accuracy. (newscientist.com)