Trump vows that the U.S. will go back to the moon, but how?

The moon

It has been 45 years since astronauts Eugene Cernan and Jack Schmidt stepped foot on the surface of the moon. They were part of the Apollo 17 mission, and the last humans to set foot on the lunar surface. The focus in recent years has been planning for a trip to Mars, not putting another man on the moon. Even NASA's Space Shuttle program last flew in 2011, so the idea of America's space agency returning to the moon was on the backburner, until earlier this week.

The promise

Despite the fact the former U.S. President Barack Obama set America's sights on Mars, current President Donald Trump promised earlier this week that NASA, along with help from various private space companies (Moon Express, SpaceX, Blue Origin, United Launch Alliance) and other countries, will return to the moon by 2020.

 Trump has pledged to restore America's leadership in space and "refocus America's space program on human exploration and discovery."   

The questions

Christian Davenport covers the defence and space industries for The Washington Post. He points out that Trump is now the third consecutive Republican president to make this promise. Neither George H.W. Bush or George W. Bush were able to follow through, and with so many unanswered questions such as who will pay, what is the timeline, and how will this work, it is unclear how Trump will be able to deliver on his promise either. 

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