40 terms

Science chapter 3 glory of the stars

Stars grouped into patterns
A device that determines the position and motion of the heavenly bodies
Sextant and octant were handheld instruments having a movable index arm that indicated the angle of elevation between a star the sun or moon and the horizon
Refractor telescope
The telescope Galileo Galilei invented
Make (a ray of light) change direction when it enters at an angle.
Objective lens
the lens or system of lenses in a telescope or microscope that is nearest the object being viewed.
Eye piece or magnifying lens
The ability of a telescope to bring out details in an image
Wave length
A slightly different angle of refraction in a given lens
Compound lens
Moderns refractors avoid chromatic aberration by using special lenses consisting of two different kinds of glass cemented together
Reflector telescope
Telescope that Sir Issac Newton created
Newtonian reflector
The arrangement in which the image is viewed through the side of a tube
Cassegrainian reflector
A more compact reflector telescope design that is easier to use
Composite telescope
A telescope that uses both mirrors and correcting objective lens to gather light
Schmidt-cassegrainian telescope
In this form the light path enters the telescope through a special lens and then continues through a hole in the main mirror as with a standard cassegrainian
Radio telescope
An instrument used to detect radio emissions from the sky, whether from natural celestial objects or from artificial satellites
Hubble space telescope
A special instrument that spans the optical and nonoptical categories of telescopes
The astronomical equivalent of latitude and longitude
Celestial equator
When the heavens are divided into northern and southern halves
A stars angular distance north or south of the celestial equator
Right ascension
A stars longitudinal position
Prime hour circle
The starting line for right ascension
A measure of its relative brightness
Red shift
The mathematical rule that relates the stretching of wavelengths of their light with increasing distances
Proper motion
Movements across the sky as we see it
Radial motion
Movement directly toward or away from us
The color of a star
Super giant
A red star that is five times larger than the sun
White dwarf
Some very hot blue white stars are that are relatively small
Eclipsing binaries
Variable star pairs like Agol
Cepheid variables
Stars that expand and contract regularly
How long a star takes to go from one bright spurt to the next
Occasionally a star may increase it brightness by twenty magnitudes or more in an explosion that practically destroys the star
A star that will be visible for several month or years that no one has recorded then it will fade away
Neutron star
An extremely dense small dark star in which atomic particles (electrons and protons) have combined to from neutrons
Star cluster
Several stars that have the same motions
Consists of millions of stars
The many types of objects that Messier and Dreyer cataloged which are clouds of gas and or dust
A massive and extremely remote celestial object, emitting exceptionally large amounts of energy and typically having a starlike image in a telescope
Black hole
The most mysterious and unusual objects in the universe.