Time in Space: If it Ain't Broke . . .

Telling the time on the Moon isn't so easy. You have two weeks of "day", followed by two weeks of "night", so looking out of the window isn't going to help. You need a reliable wristwatch.

The crew of Artemis II were all wearing one - with a specially extended strap to fit over their bulky spacesuits - when returned to Earth safely on 10 April after the first manned lunar flyby in more than 50 years.

Their NASA-issue Omega Speedmaster X-33 Gen 2 is a perfectly adequate timepiece - a battery-powered quartz, analog-LCD digital watch in a titanium case. But it's nothing to write home about.

The watch was launched in the entry-level luxury market in 2001, then discontinued from public sale in 2006.

There are plenty of newer and better watches available, in an age driven by innovation, where newest is generally regarded as best. Except when it's not. When lives could depend on it, you don't take a chance on something that's untried and untested.

That's exactly why the Artemis II mission used IBM computer processors from 2002. Today's smartphones could outsmart them in terms of speed, but the old processors are "fault tolerant". They won't crash.

Similar story with NASA's nine-year, three billion mile New Horizons mission to Pluto, launched in 2006. It relies on computers from the 1990s, which run at a snail's pace compared to today's tech, but they've been proven to be resistant to cosmic radiation.

Even more remarkable is the US Air Force's use of B-52 bombers - introduced way back in 1962 - to attack Iran's ballistic missile sites during the current war in the Middle East. Again and again it's a question of "if it ain't broke, don't fix it".

In space, a watch can be a lifesaver if there's a "Houston, we have a problem" moment.

Even today astronauts are trained to use them if the computer systems fails, to measure "burns", the short, precisely timed firings of rocket engines that adjust a spacecraft's velocity orbit, or trajectory.

Their watches also need to withstand zero gravity, extreme temperatures, and the intense vibrations of take-off and re-entry into the Earth's atmosphere.

NASA opted for the first generation of Speedmasters back in 1959, they ran like clockwork (no surprise, they were clockwork) and they stuck with the brand.

They were the watches that Neil Armstrong and Buzz Aldrin both wore on Apollo 11 in July 1969 (Armstrong actually left his in the lunar module when he famously proclaimed: "one small step for man". And back on Earth he managed to lose it.)

It's now 53 years since man last set foot on the Moon (Apollo 17, December 1972). That's due to change in early 2028, Artemis IV, when mankind returns to the lunar surface.

And there's every chance the trusty old Speedmaster X-33 Gen 2 will remain the approved watch for the mission - even though the LCD display will inevitably freeze in the sub-zero temperatures of outer space.

Have a fabulous weekend.