Exam 18: The Universe

The creation of elements inside a star is called ______________.

Which of the following is not a name used in the classification of galaxies?

The Sun's photosphere is,by mass,about 75%

The "surface" of a black hole is known as the _______________.

What type of nebula is the Horsehead?

The apparent brightness of stars is ranked according to magnitude.The brightest stars were originally ranked as what magnitude?

Eighty-eight prominent groups of stars in the sky are called the _______________.

The Greek astronomer who assigned the stars to six magnitudes was named _______________.

The imaginary,huge,apparently moving sphere on which the stars appear to be mounted is called the _______________ sphere.

In the middle of the Crab Nebula (M1)is

Clusters containing clusters of galaxies are called _______________.