what on the sun creates auroras on earth?
charged particles travel down the magnetic field lines and interact with ions
what is the relationship between auroroas and the sunspot cycle?
sunspots are created by magnetic field disturbances which were interacted with ions to create auroras
what is solar wind?
streams of protons and electrons that shoot out from the corona and travel at high speeds
what process feuls the sun and how does it work?
hydrogen fuses to form helium and the missing mass is given off as energy
what is the temperature of the photosphere compared to the temperature of the corona?
corona- 1 million k
what is a basic method for measuring distance to stars? define it
parallax-slight shift in the apparent position of a nearby star due to the motion of the orbital motion of the earth
name three factors that affect the apparent brightness of a star when seen from earth
distance temperature size
what is the evolutionary path for a low mass star?
nebula, protostar, main sequence, white dwarf, black dwarf
what is the evolutionary path for a medium mass star?
nebula protostar main sequence red giant planetary nebula white dwarf black dwarf
what is the evolutionary path of a large mass star?
nebula protostar main sequence red supergiant supernova explosion neutron star/blackhole
what do astronomers look for when they are looking for black holes?
evidence of matter being rapidly swept into regions of apparent nothingness
The point in stellar evolution when a star has used up all its fuel and is radiating away its remaining thermal energy as light is the ________ stage.
Which of the following is NOT a factor that affects the apparent brightness of a star as seen from Earth?
the age of the star
The discovery that the universe appears to be expanding led to a widely accepted theory called ___
the big bang
Based on the observed red shifts in the spectral lines of distant galaxies, astronomers conclude that ________.
the universe is expanding
A star in which light cannot escape because of the immense gravitational pull at its surface is called a ________
Star A is farther away from Earth than Star B. Both stars have the same absolute magnitude. Which of the following is true about their apparent magnitudes?
star b will have a greater apparent magnitude
During periods of high solar activity, huge cloudlike structures that appear as great arches extending from the Sun are often produced. These solar features are called ________.
The lowermost part of the sun's atmosphere that is a thin, red rim seen around the sun during a total solar eclipse is the
When a main-sequence star has exhausted the fuel in the inner region, it becomes a ________.
The layer of the Sun that radiates most of the light that reaches Earth is called the ________.