We are sure our readers have been enjoying NASA's footage of the SpaceX Falcon 9 launch to the ISS earlier today, but amid the excitement, you may have missed another historic moment for the US space programme. Listen carefully...
That's right, at around 1:10, a mission control operative explains: "Altitude 5.3 kilometres, velocity 225 metres per second, and downrange distance of six-tenths of a kilometre."
Let's take a moment to consider just how monumentous this shock injection of metric is. A couple of years back, NASA blamed legacy hardware for its inability to switch from inches to centimetres, despite warnings that its faffing "could derail efforts to develop a globalised civilian space industry".
Mike Gold of Bigelow Aerospace said: "We in the private sector are doing everything possible to create a global market with as much commonality and interoperability as possible. But NASA still can't make the jump to metric."
Well, it appears that fellow privateer Elon Musk is doing his best to kick NASA's sorry ass into the metric system, even if "six-tenths of a kilometre" still has a ring of old school about it.
We look forward to seeing if the agency, and indeed Britain, will finally succumb to pressure fall in line with the civilised world of SI units. ®