You are here

Appendix G

Octan Units of Measure

The following table defines common octan units of measure,
and lists conversion factors to units widely used by both humans and simions (on planets Earth and Aerth, respectively).

In deference to human (and potential simion) readers, all numbers here and throughout the text are expressed in the decimal system, base ten.
Octos customarily express numbers in the octal system, base eight.

Physical Quantity Octan Unit Definition Human/Simion Equivalent
Time noc 1/64 nim 1.09 seconds
nim 1/64 roh 1.16 minutes
roh 1/8 yad 1.24 hours
yad local Jopitar day
(deep interior)
9.92 hours
kew 8 yads 3.31 days
thom 8 kews 26.5 days
jope local Jopitar year 11.86 years
kilujope 83 jope 6072 years
megujope 86 3.109 million years
bevujope 89 1.592 billion years
Distance centuret 1/64 ret 1.460 centimeters
ret 8-6 depth of floating thickets 0.935 meters
kiluret 83 ret 0.479 kilometers
meguret 86 ret 245.0 kilometers
bevuret 89 ret 1.254 x 105 kilometers
light jope distance light travels in one jope 1.122 x 1014 kilometers
Mass mag mass of a 1 centuret cube
of alpha-quartz
8.246 grams
kilumag 83 mags 4.222 kilograms
Pressure rab 8-3 atmospheric pressure
at floating thickets
0.1187 bars
Temperature nevlu 8-3 absolute temperature
at floating thickets
1.119 kelvin

Time, distance, mass, and temperature are fundamental quantities in the modern octan system. The corresponding fundamental units yad, ret, mag, and nevlu were originally defined in terms of mean values at the heart of the South Equatorial Belt in the jope zero of the (archaic) calendar of Zuul. The commonly used jope and rab were then redefined in terms of the fundamental units, to match accepted values during that epoch. All the fundamental units were eventually redefined in a more precise, reproducible manner that still closely matched the original values, using dimensional universal physical constants.

Jopitar's rotation and the length of the yad were first inferred from observations of the coriolis force in the floating thickets. The standard deep-interior value was later refined through spacecraft measurements of radio emissions from Jopitar's magnetic field.

The kiluret, nevlu and rab scales were originally calibrated such that the numerical values of depth (beneath the tropopause), temperature, and pressure were all approximately 512 (which is 1,000 in the octo base-8 number system) at the level of the floating thickets. The value of the ret was then similar to a popular ancient unit of distance, based on the average length of the dextrous tentacle of a mature octo.

Octos frequently add prefixes to their basic units, to define convenient smaller or larger units.
Several of the units defined in the previous table are examples of this practice.
The following table lists and defines some of the most commonly used prefixes.

Prefix Definition
nanu x 8-9 = x 1/512 x 1/512 x 1/512
micru x 8-6 = x 1/512 x 1/512
millu x 8-3 = x 1/512
centu x 8-2 = x 1/64
octi x 8-1 = x 1/8
octu x 8
hectu x 82 = x 64
kilu x 83 = x 512
megu x 86 = x 512 x 512
bevu x 89 = x 512 x 512 x 512
teru x 812 = x 512 x 512 x 512 x 512