↑ Pyle, Rod (2012). Destination Mars. Prometheus Books. tr. 73–78. ISBN978-1-61614-589-7. Mariner 8 launched... but failed early in flight and ended its mission by splashing into the Atlantic Ocean.... [Mariner 9] was the first spacecraft to enter orbit around another world.... [It] continues to orbit Mars to this day, sailing around the planet deaf and dumb in the cold darkness.... [Mariners 1-10 were] a demonstration of what a bargain these early missions were. For a total cost of $554 millions, the inner solar system had been opened, and brilliantly.
