Appendix A

Glossary of terms used on this website


Albedo — the fraction of light reflected by a planet after striking it

Angiosperm — the class of flowering plants characterized by developing seeds in an ovary

Astronomical unit — a distance of astronomical measurement approximately equal to the distance between the Earth and its sun

Biome — a general term referring to one of several classifications of biological regions, such as tundra, chaparral, deciduous forest, desert grassland or rain forest. Biologists define unique classifications of biomes for each planet.

bcet — “before common era terrestrial (calendar),” placed after dates before the year zero in the Gregorian calendar on Earth.

cetc —“common era terrestrial calendar,” placed after dates expressed in the Gregorian calendar on Earth. All dates in this bulletin are expressed cetc, unless otherwise noted. Other planets use different calendars depending on their location and the length of their year.

Earth standard year — a measurement of time made by atomic clocks. It is equal to the sidereal year 2154 cetc on Earth

Earth standard hours — a measurement of time computed by atomic clocks and equal to exactly 1 /24th of the sidereal day on 1 January 2154

Eccentricity — a mathematical measurement of the ”egg shape” or oblateness of an ellipse. Precisely, the eccentricity of an ellipse whose semi-major axis equals ‘a’ and whose foci lie a distance ‘d’ apart is equal to d/a. The more elongated the ellipse, the larger the value of its eccentricity.

Ecliptic plane — the plane of orbit of a planet about its sun

Ecosphere — the region of space surrounding each star bounded by two imaginary, concentric spheres, in which a habitable planet could theoretically exist

Equinox — the first day of spring or fall; more precisely, that moment at which the intersection of the planet’s equator and its ecliptic point directly toward its sun

Extraterrestrial — an adjective referring to things outside of the Earth

GAIL—the Galactic Association of Intelligent Life, an association of scientifically advanced, technologically sophisticated life forms from several planets, organized to promote the peaceful exploration and development of space and the advancement of their common knowledge

GAILE — the Earth’s administrative branch of GAIL, which engages in exploration and colonization of space on behalf of the people of Earth

Genus — the biological classification immediately above species; the scheme of classification in descending order is kingdom, phylum, class, order, genus and species.

Hyperspace — all spaces outside of the “normal” space-time continuum in which the Earth and all known stars and planets exist. Starships travel through hyperspace in order to shorten travel time between the stars.

light year — an astronomical measure of distance equal to the distance traveled by a beam of light in one Earth standard year.

Obliquity — the angle between a planet’s equator and the plane of its orbit about its sun (ecliptic)

Parsec — a measure of distance approximately equal to 3.26 light years, now rarely used. A star lying one parsec from Earth would display an annual parallax of one second (travel in an elliptic path spanning one second of arc in the sky).

Photon drive — a type of modern starship engine, sometimes called a Planck’s torch

Phylum — the biological classification immediately below kingdom (see genus). Human beings belong to the phylum chordata,

Primary — in astronomy, the object about which a smaller object orbits. The sun is the primary of Earth and Earth is the primary of the moon,

Protists — in the biological scheme of classification, a third kingdom consisting of life forms, mostly microscopic, which are neither plant nor animal

Sol —the proper name of the Earth’s sun

Standard Earth time — time measured relative to an atomic clock standard on Earth. Each hour of standard Earth time equals 1/24 of the Earth standard day. All times expressed in this bulletin have been converted to Earth standard times, though each planet has its own time standard.

sun — the star about which any planet orbits

Star type — a system of classifying stars according to their temperature and size. Temperature classifications from hottest to coolest are O,B,A,F,G,K,M. The number following the letter further divides the scale into subclasses. For example a G2 star is hotter than a G3. A roman numeral designation following the temperature class indicates the size of the star, from I for giants to VI for subdwarfs. All habitable planets orbit dwarf stars of size V (five). Example;

Earth’s sun is a type G2V star.

Terrestrial — on or of the Earth. Sometimes used in a more general sense to describe Earth-like planets. The eight colonies may be classified by planetologists as terrestrial.

Von Roenstadt’s habitability factor — an index which considers a variety of physical and biological factors to gauge a planet’s suitability for Human life. Though now superceded by more complex analysis, the Roenstadt factor provides a simple comparison for non-scientists. Earth is defined as 1.0. Planets habitable only in artificial environmental structures have Roenstadts less than 0.5. Totally uninhabitable worlds have Roenstadts of 0. GAILE will not consider colonizing planets with factors less than about 0.75.

Warp — the deformation of space caused by gravity or by high rates of acceleration. Starships “warp” space prior to making the transition to hyperspace, hence this transition is sometimes called “space warp” or “warp maneuvers.”