EVEN MORE weird and humorous measurements used in engineering

In the first article of weird and humorous engineering measurements, we covered everything from Donkey Power to Jiffy to a Garn, and more.  

While the list might have seemed fairly complete in its depth of oddities, a bit more research into the topic covered even more curious definitions in phrases used by engineers and technology professions. 

Check them out below:

What are Pirate Ninjas ?

Formally, Pirate Ninjas are defined as kilowatt hours per sol. It comes from the mind of Andy Weir, the author of The Martian book and movie, who used in the following quote from the story:  

“You know what? “Kilowatt-hour per sol” is a pain in the a** to say. I'm gonna invent a new scientific unit name. One kilowatt-hour per sol is… it can be anything… um… I suck at this… I'll call it a ’ pirate-ninja’.”

Weir said in an interview that the Curiosity rover team at the Jet Propulsion Laboratory references milli-Pirate-Ninjas in their meetings, thus giving credence to the term showing up on this list. 

What is a Rack Unit ?
A single rack unit (U) is 1 and three quarter inches—it’s used to measure AV and computing equipment that can be placed in a rack. They’re typically denoted with a number that references the total units in a rack. So, a 4U server enclosure is seven inches high. 

What is a Beard-Second ?
A unit of length inspired by the light year the Beard-Second is used for very short distances like those seen in integrated circuits. Specifically, it’s defined as the length an average beard grows in one second—100 angstroms (10 nanometer), as defined by Kemp Bennett Kolb, though it is worth pointing out that Google Calculator gives the Beard-Second a value of 5 nanometers.

What is a Ton of refrigeration ?
When someone references a ton of refrigeration, they are referring to the total amount of energy that gets removed when melting one ton of ice over the course of 24 hours. This comes from the days when large blocks of ice were used for cooling—today, it’s used to describe the heat-removal capabilities of refrigerators / chillers. A single ton of refrigeration equals 12,000 BTU/h, or 3.517 kW.

What is a Banana Equivalent Dose ?
Just like nearly all organic material, bananas naturally contain a particular amount of radioactive isotopes. The Banana Equivalent Dose refers to the additional dose a human will absorb from eating a single banana. It is used to express the severity of exposure to radiation (accidental, medical, weapon, etc.) in a way that makes the most sense to the general public. It is equal to roughly 78 nanosieverts. 

What is an Erlang ?
Named after A. K. Erlang, the Erlang is a dimensionless unit used in telephony as a statistical measure of the offered intensity of telecommunications traffic on a group of resources. One Erlang refers to a single resource being in continuous use; two channels being at fifty percent use, and so on. Many telecom management and forecasting software use it on a day-to-day basis.

What is a Nanoacre ?
Equal to 0.00627264 sq inches (4.0468564224 mm2) or the area of a square of side length 0.0792 in (2.01168 mm), the nanoacre is a unit of real estate on a VLSI chip. Developers often poke fun at the fact that the cost of a VLSI nanoacre has gone up in the same range as actual acres in Silicon Valley once you figure in design and fabrication costs. 

What is a Jansky ?
A Jansky is a unit of electromagnetic flux used in radio astronomy. Named after the famed radio astronomer Karl Jansky, it is equivalent to 10−26 watts per square meter per hertz (= 10−26 kg/s2 in base units, about 8.8×10−31 BTU/ft2). For reference, the brightest natural radio sources have flux densities of the order of 1 to 100 Jansky.

What is the Gasoline Gallon Equivalent ?
To help US citizens better understand units of energy, especially with the proliferation of efficiency and fuel economy vehicles hitting the market, the US Environmental Protection Agency introduce the gallon gasoline equivalent. It is defined as 33.7 kWh, or about 1.213×10⁸ joules, and when shoppers are touring EVs on the showroom floor, they’ll typically see the car’s range expressed as miles per gallon gasoline equivalent.

What is a Crab ?
A crab is typically used as a unit of measurement for calibrating X-ray telescopes. By definition, it refers to the intensity of X-rays emitted from the Crab Nebula at a given photon energy of up to 30 kiloectronvolts. One crab is about 24 pW / m² . When measuring the X-ray intensity of less energetic sources, the milliCrab is used. 

What is a Nibble ?
While it might sometime be spelled “nybble” or “nybl”, the nibble refers to a quantity of data generally equal to 4 bits (half of the common 8-bit byte). It’s most often used to describe the amount of memory used to store a digit of a number stored in binary-coded decimal format, or to express a single hexadecimal. 

What is the difference between a Microcentury and a Nanocentury ?
While both reference a unit of time measurement, one is slightly in jest while the other is rooted in history.

The term microcentury was first coined by mathematician John von Neumann to denote the maximum length of a lecture. Specifically, it’s equal to 52 minutes and 35.69 seconds, or exactly one millionth of a century. 

A nanocentury, meanwhile, is believed to have started by IBM in 1969 from the design objective “never to let the user wait more than a few nanocenturies for a response.” Specifically, it’s equal to 3.155 seconds. 

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