July is always a good time to assess where U.S. human space exploration has been and where it’s going. This year, July 20 marks the 40th anniversary of Viking, which in 1976 became the first spacecraft to land on Mars. And just seven years — to the day — before Viking’s amazing feat, humans first set foot on another world, when Neil Armstrong and Buzz Aldrin set the Apollo 11 lunar module Eagle down in the moon’s Sea of Tranquility on July 20, 1969.

These ground breaking milestones share more than a date on the calendar. They share the legacy of scientific curiosity, technological development and amazing feats of engineering that are driving today’s Journey to Mars. Today, NASA’s fleet of orbiters and rovers are studying the Red Planet, while astronauts on the International Space Station are learning how to live off the earth for longer periods of time. Meanwhile, workers across America are hard at work developing the hardware and new technologies that will take humans farther from Earth than ever before, including the Orion spacecraft and the Space Launch System, the most powerful rocket ever built.

Echoing Neil Armstrong, NASA’s giant leaps are built on a series of small steps. NASA’s next giant leap – sending humans to Mars in the 2030's – will be the culmination of a long series of small steps, some of which are taking place this summer.