NASA is building a space clock. Now you might be asking yourself: "Why, do they not have clocks in space already?"
They do, but the fact is they're just nowhere near accurate enough. What they need are clocks that can travel for 15 years and never lose a second.
To accomplish this feat NASA is building the Deep Space Atomic Clock (DSAC). Hidden within the fuselage will be a miniaturised, ultra-precise mercury-ion atomic clock, so accurate that it will only drift 1 nanosecond every 10 days.
While the idea of sending an ultra-precise clock into space might not sound like the edge of technical innovation, the fact is DSAC will help us create the ultra-precise navigation systems that will eventually send humans to Mars and beyond.
In the same way that sailors constantly perfected their navigational tools, so to is NASA working on a system that can survive years and even decades of space travel, taking into account movement, interference and more.
Mars is a particular focus. With DSAC the hope is that spacecraft will be able to safely navigate their way to Mars and then perform the complex calculations needed to safely land on the planet's surface.