This Mars Probe Went Missing

NASA's Mars Observer spacecraft went silent on August 21, 1993, just days before reaching Mars, joining many failed missions to the Red Planet. Sending probes to Mars is challenging due to its thin atmosphere, which provides little drag for landing, and the 140-million-mile communication distance. The Observer's failure, likely caused by a fuel leak, demonstrated that repurposing near-Earth equipment for deep space missions can have costly consequences.