A telescope that uses only lenses to concentrate the light from an object and focus it into an image.
What is a refractor telescope
100
The lens nearest the object in a compound optical instrument. In astronomy, the large, light-gathering lens of a refractor telescope.
What is an objective lens
100
A term used to classify the largest and most luminous stars. Typically they are 15-20 times as massive as our sun, but they are several hundred times as large and are much more luminous.
What is a Super Giant
100
One of the first people to investigate the use of lenses.
Who is Roger Bacon
100
Celestial latitude. Angular distance north or south of the celestial equator measured in degrees.
What is declination
200
Any one of several telescope designs that uses a concave mirror as the primary light-gathering optical component.
What is reflector telescope
200
Two or more lenses made of different kinds of glass mounted together to correct for chromatic aberration.
What are compound lenses
200
A very dense, very bright star of about the same mass as the sun but only about a hundredth of its diameter. White dwarfs in binary systems may produce novas. Some may be remnants of supernovas.
What is a white dwarf
200
Made the first telescopes to appear in Holland in 1608.
What is Hans Lipperhey
200
Celestial longitude; measured in hours, minutes, and seconds east of the prime hour circle.
What is right ascension
300
A telescope that uses both a primary mirror and a large objective corrective lens as the main light-gathering elements of the telescope.
What is a composite telescope
300
The eyepiece of an optical instrument such as a telescope.
What is ocular
300
Two stars revolving around each other such that they periodically pass in front of each other relative to the observer.
What is an Eclipsing Binary
300
Introduced an orderly system for identifying particular stars within a constellation.
What is Johann Bayer
300
The reference line for celestial longitude, extending from the north to the south celestial poles through the point of the vernal equinox. (See vernal equinox.) Position of zero hours of right ascension.
What is the prime hour circle
400
A radio receiver with a large, dish-shaped antenna system. It receives, focuses, amplifies, and analyzes radio waves from outer space.
What is a radio telescope
400
The ability of a lens or mirror to visually separate two objects that are separated by a small angle.
What is resolution
400
A type of star that changes in brightness regularly, apparently because it expands and contracts on a regular basis.
What is a cepheid variable
400
Was the first astronomer to detect proper motion.
What is Edmund Halley
400
The day that the sun’s overhead noon position crosses the equator (March 21). At the equinox, day and night are of equal length in all parts of the earth.
What is vernal equinox
500
An astronomical reflecting telescope placed in earth's orbit by the space shuttle in 1990. The HST has provided amazing images of the universe that changed the course of astronomy.
What is the Hubble Space Telescope
500
In general the bending of a wave when it changes speed because the material through which it is moving changes in some way. It occurs in optics when light passes from air into glass and in water waves when the bottom becomes shallower than the wave base.
What is refraction
500
A star that suddenly increases its apparent brightness by about twenty magnitudes because of an explosion that essentially destroys it.
What is a supernova
500
Drew up a catalog of one hundred star clusters (did not know they were star clusters).
What is Charles Messier
500
The measure of the brightness of a star; a measure of the amount of energy released by an earthquake.