[LEAPSECS] drift of TAI

[Magnus Danielson]

Adi Stav wrote:

> (Hi, I'm Adi, long-time lurker, first-time caller)

> 

> On Mon, Sep 15, 2008 at 01:29:13AM -0700, Rob Seaman wrote:

>>> In the absence of days and years, though, calculations that involve  

>>> only metric units are a lot easier than what we presently put up with.

>> Hence the prevalence of radians in everyday use :-)

> 

> That's a separate issue. You can base your angle units on perimeter or 

> radius length, and then you can divide them into decimal or sexagesimal

> subunits as a completely independent decision. Several systems dividing 

> the circle into decimal units have been propsed and used in practice, 

> some still today; on the other hand, it's easy to divide the radian into

> sexagesimal units. (I'm surprised that I'd never encountered

> such a system -- dividing the radian into 60 "degrees", each divided

> into turn into 60 minutes and 3600 seconds, would not only have given

> "degrees" that are only slighly (5%) smaller than perimetral degrees,

> but also be more consistent with regards to division by 60.)

> 

> Actually, our radians don't require any particular radix at all, we use 

> them as whole units. A computer might display a radian in decimal

> notation, yet stores them in binary floating-point representation, or as

> nominator-denominator pair, or whatever. Nothing decimal about them.


There are several military systems that approximate radians in this 
fashion. Used when making precission measurements (of its time in the 
field) for measuring the destination of ordinance.

Cheers,
Magnus