Astronomical Dictionary Page #3

Basalt

Fine-grained igneous rock (rich in mafic minerals) that has erupted onto the surface....

Atlas

In Greek mythology, brother of Prometheus and grandfather of Hermes (Mercury). Condemned to stand fo...

Atla

In Norse mythology, a giantess, mother of Heimdall....

Arachnoid

Spider or cobweblike feature on the surface of Venus, typically having a diameter of about 100-km an...

Apollo

In Greek mythology, one of the twelve Olympian gods. God of prophecy, healing, archery, music, youth...

Aphrodite

One of the twelve Greek Olympian gods. Goddess of Love (Roman name, Venus), daughter of Zeus and Dio...

Antipodal point

The opposite point with respect to any given point....

Anorthosite

A type of igneous rock composed almost entirely of feldspar, a group of minerals that make up about...

Altimetry

The measurement of elevation or altitude....

Albedo

The ratio of the amount of solar radiation reflected from an object to the total amount incident upo...

Akna

In Native American traditions from Mexico and from the Arctic, "Moon" (Wife of the Sun) and "The Mot...

Adams

John Couch Adams (1819-1892) English astronomer. One of the discoverers of the planet Neptune....

Achondrite

A stony meteorite, coarsely crystallized, with sizable fragments of various minerals visible to the ...

Aa

A basaltic lava with a rough, jagged surface....

Granulation

The mottled, orange peel, appearance of the Sun's surface; caused by convection within the Sun and o...

Geomorphology

The study of the external structure, form, and arrangement of rocks in relation to the development o...

Geyser

A type of hot spring that intermittently erupts jets of material. ...

Giotto

Giotto di Bondone (1267?-1337) Italian medieval painter, architect, and sculptor....

Graben

A long, relatively depressed crustal unit or block that is bounded by faults along its sides; a tro...

Gula

One of the primary goddesses of the Akkadian and Babylonian peoples. The mother-goddess and great ph...

Heliocentric

Sun-centered. Positions of planets, including the Earth and Moon, referred to the center of the Sun...

Hadley

John Hadley (1682-1744) English mathematician and inventor. Built first serviceable reflecting teles...

Halley

Edmond Halley (1656-1742) English astronomer. In 1758, predicted accurately the return of a comet pr...

Herschel

Sir William Herschel (1738-1822). British astronomer. Built reflecting telescope of superior quality...

Hestia

In Greek mythology, one of the twelve Olympian gods. Sister of Zeus and goddess of the hearth and ho...