To celebrate Metric Week (Oct. 5-11), the National Institute of Standards and Technology would like to introduce you to the League of SI Superheroes. The League of SI Superheroes use their incredible powers of measurement to perform amazing feats of science and engineering.

Measurement is an incredibly powerful tool. Measurements are how we describe what we know, uncover what we don't know, ensure quality and enable creativity.

Rear Admiral and computing pioneer Grace Hopper famously said, "One accurate measurement is worth a thousand expert opinions." What she meant is that opinions are fine, and expert opinions are even better, but they aren't knowledge until there are measurements to back them up.

The customary units in the United States grew out of our everyday experience. Gallons, feet and pounds were conveniences based on prescientific notions of accuracy and repeatability that served, and continue to serve, people's everyday needs adequately enough (though their continued use does act as a barrier to trade and can occasionally lead to mishaps).

It was around the time of the Enlightenment that people began to get serious about measurement. Scientists realized that they needed a rational set of interrelated measures rooted in natural constants if they were going to make any further progress. This was the driving force behind the creation of the International System of Units, or SI, which, even though its use is not mandatory, serves as the foundation for all the traditional units with which we in the United States are most familiar.

Some of the most famous figures in science have lent their skills (and their names) to the SI, and the drive to improve those and related measurements has led to groundbreaking scientific and technological achievements, including four Nobel Prizes (and counting) for NIST scientists.

Today, we welcome the newest champions of measurement, the League of SI Superheroes. Emerging from their environmentally shielded headquarters around the globe, the superheroes are dedicated to the fight against uncertainty, imprecision and inaccuracy and to improving the quality of our lives and the things we build.

The League of SI Superheroes was designed to encourage students to learn about metric measurements as they consider science, technology, engineering and mathematics (STEM) careers. SI familiarity and fluency must be developed along the STEM career pipeline to prepare the future workers with essential measurement skills.

Educators are encouraged to use this resource in their classrooms when introducing the seven base SI units to students.

The League of SI Superheroes are:

Meter Man: With his laser interferometer eyes, graduated arms and extendable body, no dimension is too big or too small for Meter Man to measure.

The Mole: Able to sniff out and count the atoms of every element, the Mole is a master of chemistry.

Professor Second: By reading the vibrations of her laser-cooled cesium atoms, Professor Second can synchronize any frequency and calibrate any clock.

Monsieur Kilogram: Monsieur Kilogram loves lifting weights, and it shows. With his balance scale arms, no mass is too big or too small for him measure.

Ms. Ampere: Ms. Ampere rules the flow of electrons—electrical current—and makes sure that the right amount gets where it needs to go.

Dr. Kelvin: Dr. Kelvin heats up or cools down objects by speeding up or slowing down the particles inside them. He can also measure the temperature of anything in the universe with his trusty thermometer.

Candela: Don't let her small size fool you. Candela's power over light helps to brighten the whole world.

The League of SI Superheroes' work is never done. They toil tirelessly behind the scenes to make sure the measurements that interweave our lives are as accurate and precise as possible. And they hope to release another of their harrowing adventures to the public soon.

In the meantime, watch their pilot episode, Desperate Measures, and let them know what you think about their work. And be sure to let them know if you are in need of their assistance.

If you would like to learn more about the SI, check out these fine resources:

Teachers can also request a classroom set of SI educational materials by submitting their contact information and grade level to TheSI@nist.gov.

More information about Metric Week can be found at these sites:

See you soon!