## What slide rules did NASA use?

NASA chose a 5-inch, metal rule, model “N600-ES,” manufactured by the Pickett Company for their use. It was a model that was popular among engineers, scientists and students at the time. No modifications were needed for use in space.

### How does a circular slide rule work?

Circular slide rules come in two basic types, one with two cursors, and another with a free dish and one cursor. Circular slide rules also eliminate “off-scale” calculations, because the scales were designed to “wrap around”; they never have to be reoriented when results are near 1.0â€”the rule is always on scale.

#### Are old slide rules worth anything?

By the end of the 1970s, all the slide rule manufacturers died. So there were several models sold that had a math calculator on one side and a slide rule glued to the back to do those other functions. Those are worth a lot of money if you’re collecting.

What was the best slide rule?

Faber-Castell 2/83N Novo-Duplex: Size 38 x 7 cm, 30 scales, plastic. This model is regarded by some as one of the finest slide rules ever made. Its combination of size, build, sophistication of scales offered and attractive use of colour gives a slide rule that impresses!

What slide rule went to the moon?

In September 2007, Heritage Auction sold the Pickett slide rule that Apollo 11 astronaut Edwin “Buzz” Aldrin took to the moon. The Pickett Model N600-ES (Eye Saver) Log Log Speed Rule, was 6 inches long with 22 five-inch scales.

## When did slide rules stop being used?

The use of slide rules continued to grow through the 1950s and 1960s even as digital computing devices were gradually introduced; but around 1974 the pocket calculator made the slide rule largely obsolete and most suppliers left the business.

### How do slide rules use logarithms?

The slide rule made it easier to utilize the log relations by developing a number line on which the displacement of the numbers were proportional to their logs. The slide rule eased the addition of the two logarithmic displacements of the numbers, thus assisting with multiplication and division in calculations.

#### Can you still buy slide rulers?

There are many pages about slide rules on the web, and you can still buy brand new slide rules (40 years old but never used, and still in their factory supplied box) in various places. This is one of the fanciest and most beautiful slide rules ever made, a Faber Castell Novo Biplex 2/83 N.

What can a slide rule calculate?

In its simplest form, the slide rule adds and subtracts lengths in order to calculate a total distance. But slide rules can also handle multiplication and division, find square roots, and do other sophisticated calculations.

Do they still make slide rules?

Though they’re no longer produced, the company still stocks around 1,200 or so and occasionally gets an order for some. Why would anyone still want to buy a slide rule, when inexpensive calculators are so readily available? According to Haase, slide rules are better suited to some functions than are calculators.