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ndar, or 46 b. c. -- Julian period, a chronological period of 7,980 years, combining the solar, lunar, and indiction cycles (28 x 19 x 15 = 7,980), being reckoned from the year 4713 B. C., when the first years of these several cycles would coincide, so that if any year of the period be divided by 28, 19, or 15, the re…

One of the planets of the solar system, the fourth in order from the sun, or the next beyond the earth, having a diameter of about 4,200 miles, a period of 687 days, and a mean distance of 141,000,000 miles. It is conspicuous for the redness of its light.

f a variable quantity during one cycle of variation; as, mean distance; mean motion; mean solar day. Mean distance (of a planet from the sun) (Astron.), the average of the distances throughout one revolution of the planet, equivalent to the semi-major axis of the orbit. -- Mean error (Math. Phys.), the average error o…

magic lantern, used esp. for throwing a magnified image of an opaque object on a screen, solar or artificial light being used.

One of the planets of the solar system, being the one nearest the sun, from which its mean distance is about 36,000,000 miles. Its period is 88 days, and its diameter 3,000 miles.

magnified by another lens called the ocular or eyepiece. -- Oxyhydrogen microscope, and Solar microscope. See under Oxyhydrogen, and Solar. -- Simple, or Single, microscope, a single convex lens used to magnify objects placed in its focus.

ng from any point of the ecliptic to the same again, equal to 27 d. 7 h. 43 m. 4.7 s. -- Solar month, the time in which the sun passes through one sign of the zodiac, in mean length 30 d. 10 h. 29 m. 4.1 s.

A secondary planet, or satellite, revolving about any member of the solar system; as, the moons of Jupiter or Saturn.

A faint, cloudlike, self-luminous mass of matter situated beyond the solar system among the stars. True nebulæ are gaseous; but very distant star clusters often appear like them in the telescope.

Kant, Herschel, Laplace, and others. As formed by Laplace, it supposed the matter of the solar system to have existed originally in the form of a vast, diffused, revolving nebula, which, gradually cooling and contracting, threw off, in obedience to mechanical and physical laws, succesive rings of matter, from which su…

wheelwork, the relative size, periodic motions, positions, orbits, etc., of bodies in the solar system.

to that face, parallel perspective. -- Perspective shell (Zoöl.), any shell of the genus Solarium and allied genera. See Solarium.

used in the composition of the friction surface on which safety matches are ignited. -- Solar phosphori (Chem.), phosphorescent substances which shine in the dark after exposure to the sunlight or other intense light.

nguished from a comet by the absence of a coma, and by having a less eccentric orbit. See Solar system.

The act of going before, or forward. Lunisolar precession. (Astron.) See under Lunisolar. -- Planetary precession, that part of the precession of the equinoxes which depends on the action of the planets alone. -- Precession of the equinoxes (Astron.), the slow backward motion of the equinoctial points along the eclip…

That which is prominent; a protuberance. Solar prominences. (Astron.) See Solar Protuberances, under Protuberance.

nt surface; a swelling or tumor on the body; a prominence; a bunch or knob; an elevation. Solar protuberances (Astron.), certain rose-colored masses on the limb of the sun which are seen to extend beyond the edge of the moon at the time of a solar eclipse. They may be discovered with the spectroscope on any clear day.…

ant or reflecting point; a single element of light or heat propagated continuously; as, a solar ray; a polarized ray.

od, or of a tint resembling that color; of the hue of that part of the rainbow, or of the solar spectrum, which is furthest from the violet part. "Fresh flowers, white and reede." Chaucer. Your color, I warrant you, is as red as any rose. Shak.

consisting of a brass ring suspended by a swivel, with a hole at one side through which a solar ray entering indicated the altitude on the graduated inner surface opposite.