S^C (_.
ACHROMATIC OBJECTIVE LENS. consists of two different lenses
very close together, or even in contact, to unite the
different color rays over a major portion of the visual
spectrum so that they come to a common focus. Whereas,
with a single convex lens, the blue rays come to a focus
at a point a little nearer the lens than the red rays do.
ALBEDO. is the percentage of sunlight foalling upon a planet,
a satellite, or an asteroid that is reflected back into
space and therefore makes the body visible.
ALTITUDE. is the angular distance of a celestial body above
the horizon, measured along a vertical circle through the
object to the zenith.
AMPLITUDE. is the range of variability such as the light of
a variable star, or the width of a vibration.
ANGULAR DIAMETER. is the angle subtended by the diameter of
an object.
ANGULAR MOMENTUM. is the momentum of an object spinning on
its axis (as in the case of a flywheel or a planet), or in a
planets revolution around the sun. In the latter, angular
momentum is the product of the mass of the revolving body
times the area swept by the radius, vector; and is the basis
of Kepler's Second Law, the conservation of angular momentum.
APPARENT MAGNITUDE. is the apparent brightness of a body such
as a planet or star seen from the distance of an observer.
Each succeeding magnitude step is dimmer than the preceding
magnitude by an amount equal to the fifth root of 100, equal
Tombaugh, Clyde William, 1906-1997. Out of the darkness: The planet Pluto; Glossaries, vocabularies, etc.
Digital Publisher
New Mexico State University Library
Collection
NMSU Department of Astronomy: Clyde W. Tombaugh Papers
Digital Identifier
Ms0407pp053005_0010001.tif
Source
Scan produced from physical item held by the NMSU Library Archives & Special Collections Department
Type
Text
Format
image/tiff
Language
eng
OCR
S^C (_.
ACHROMATIC OBJECTIVE LENS. consists of two different lenses
very close together, or even in contact, to unite the
different color rays over a major portion of the visual
spectrum so that they come to a common focus. Whereas,
with a single convex lens, the blue rays come to a focus
at a point a little nearer the lens than the red rays do.
ALBEDO. is the percentage of sunlight foalling upon a planet,
a satellite, or an asteroid that is reflected back into
space and therefore makes the body visible.
ALTITUDE. is the angular distance of a celestial body above
the horizon, measured along a vertical circle through the
object to the zenith.
AMPLITUDE. is the range of variability such as the light of
a variable star, or the width of a vibration.
ANGULAR DIAMETER. is the angle subtended by the diameter of
an object.
ANGULAR MOMENTUM. is the momentum of an object spinning on
its axis (as in the case of a flywheel or a planet), or in a
planets revolution around the sun. In the latter, angular
momentum is the product of the mass of the revolving body
times the area swept by the radius, vector; and is the basis
of Kepler's Second Law, the conservation of angular momentum.
APPARENT MAGNITUDE. is the apparent brightness of a body such
as a planet or star seen from the distance of an observer.
Each succeeding magnitude step is dimmer than the preceding
magnitude by an amount equal to the fifth root of 100, equal
