Why NASA wants to return to the moon before sending humans to Mars

Before landing the first humans on Mars, NASA wants to return to the lunar surface -- but in a way that we've never explored the moon before.
When the uncrewed Artemis I mission launches on Monday, August 29, it's just the first step toward the future of space exploration.
The last crewed landing on the moon, Apollo 17, was nearly 50 years ago. The final Apollo mission's record for the longest crewed deep space flight still stands: 12.5 days.
Through the Artemis program, which aims to land humans at the unexplored lunar south pole and eventually on Mars, astronauts will go on long-duration deep space missions that test all of the bounds of exploration.
"We're going back to the moon in order to learn to live, to work, to survive," said NASA administrator Bill Nelson during a news conference earlier this month.
"How do you keep humans alive in those hostile conditions? And we're going to learn how to use the resources on the moon in order to be able to build things in the future as we go -- not a quarter of a million miles away, not a three-day journey -- but millions and millions of miles away on a months and months if not years-long journey."
NASA astronaut Randy Bresnik discussed the importance of using lunar exploration as a way to prepare for landing on Mars during a NASA briefing on Saturday.