Gal´axy. The Milky-Way.
Gemini (jem´i-nī). The third sign or constellation in the zodiac, which the sun enters about the 21st of May.
Geocentric (jē-o-sen´trik) Par´allax. The apparent change of a body’s place that would arise from a change of the spectator’s station from the surface to the center of the earth.
Ha´lo. A luminous circle, usually prismatically colored round the sun or moon, and supposed to be caused by the refraction of light through crystals of ice in the atmosphere.
Heliocentric (hē-li-o-sen´trik) Par´allax. The arc of the great circle of the celestial sphere, drawn from the heliocentric to the geocentric place of a body.
Heliometer (hē-li-om´e-ter). An instrument for measuring with exactness the apparent diameter of the sun, moon, planets, etc.
Hori´zon. A circle touching the earth at the place of the spectator, and bounded by the line in which the earth and skies seem to meet.
Le´o (Lat., the Lion). The fifth sign of the zodiac which the sun enters about the 22d of July.
Libra (lī´bra), the Balance. The seventh sign of the zodiac, which the sun enters at the autumnal equinox, in September.
Luna´tion. The period of a revolution of the moon round the earth, or the time from one new moon to the next.