Nasa astronaut Karen Nyberg, Expedition 37 flight engineer, using the Space Linear Acceleration Mass Measurement Device (SLAMMD) in the Columbus laboratory aboard the Earth-orbiting International Space Station. Image Credit: Nasa

Today, we have rulers, scales, tapes and many more measuring devices to weigh and size things around us. But, did you ever wonder how people did it when these things hadn’t been invented yet?

Click start to play today’s Crossword and name all the common measurements.

People’s first standard for measurement was the human body itself, and length units based on the body were used for thousands of years. The forearm, thumb, finger, foot and span of the hand were common measurements used in ancient times.

But as the Age of Discovery (the period between 15th to 18th century) came to an end in Europe, and industry grew across nations, there was a need for a more unified form of measurement. In 1791, France proposed the unit of the metre, which means “to measure” in Greek, and voilà! It became the accepted standard for measurement across the globe.

Today, only three countries do not use the metric system in an official capacity – Myanmar, Liberia and the United States – although they do use elements of it in various industries.

Now, all this is great when you want to weigh yourself and you are standing on the ground on Earth. But how do astronauts weigh themselves in their zero gravity space shuttles?

The lack of gravity in space means that their weight is essentially zero all the time. But while weight can change depending on the gravitational force, the mass of objects is always constant. And that’s what astronauts measure when they want to calculate their weight.

The US space agency National Aeronautics and Space Administration (Nasa) has a weighing device called the Space Linear Acceleration Mass Measurement Device (SLAMMD), which uses Newton’s Second Law of Motion to generate a force against the astronaut. Since the force is a known quantity, the resulting acceleration is used to determine the astronaut’s mass, through the equation F=ma2.

Can you find all the common measurements in our Crossword? Let us know if you enjoyed it at