ASTRONOMY 101 FINAL EXAM
Explain the physical reason why we on Earth experience day and night.
Earth rotates about an axis of rotation once every 24 hours.
What is a light year?
The distance light travels in one year.
Approximately how far is the Sun from Earth?
1 AU, 150 million km, 93 million miles, 8 light minutes
About how far is the closest star to the Sun?
4 light years
Explain why Earth has seasons.
Earth's axis is tilted with respect to the orbital plane. When the northern hemisphere
is tilted toward the Sun it is summer, even though we are further from the Sun.
,Objects in the sky rise in the east and set in the west because Earth rotates from
___ to ___ about its axis.
West to East
What two main factors dictate how bright a star is as seen from Earth?
How intrinsically bright it is and how far away it is.
What are commonly recognized star patterns known as?
Constellations
What is significant about the Zodiac in the sky?
They lie along the plane of the ecliptic (the plane of the solar system)
Explain why stars appear at the same locations on the celestial sphere while the
Sun, Moon, and planets move during the course of the year.
The stars are so incredibly far away that even though they are moving, the motion is
hardly recognizable from Earth.
, List the 7 major types of electromagnetic radiation (light) from highest to lowest
energy.
Gamma, x-ray, ultra violet, visible, infrared, microwave, radio wave
What is the light carrying particle known as?
Photon
A fundamental limitation of a telescope's ability to resolve images, based on the
wave-like nature of light is known as _____.
Diffraction
What can be determined by the peak of a blackbody spectrum?
Peak indicates the temperature of the object
How would the blackbody spectrum of stars that are the same temperature differ
between a large and small star?
The peaks would be at the same location, since they are the same temperature, but
the peak would be higher for the larger star (more energy emitted per second)
Explain the physical reason why we on Earth experience day and night.
Earth rotates about an axis of rotation once every 24 hours.
What is a light year?
The distance light travels in one year.
Approximately how far is the Sun from Earth?
1 AU, 150 million km, 93 million miles, 8 light minutes
About how far is the closest star to the Sun?
4 light years
Explain why Earth has seasons.
Earth's axis is tilted with respect to the orbital plane. When the northern hemisphere
is tilted toward the Sun it is summer, even though we are further from the Sun.
,Objects in the sky rise in the east and set in the west because Earth rotates from
___ to ___ about its axis.
West to East
What two main factors dictate how bright a star is as seen from Earth?
How intrinsically bright it is and how far away it is.
What are commonly recognized star patterns known as?
Constellations
What is significant about the Zodiac in the sky?
They lie along the plane of the ecliptic (the plane of the solar system)
Explain why stars appear at the same locations on the celestial sphere while the
Sun, Moon, and planets move during the course of the year.
The stars are so incredibly far away that even though they are moving, the motion is
hardly recognizable from Earth.
, List the 7 major types of electromagnetic radiation (light) from highest to lowest
energy.
Gamma, x-ray, ultra violet, visible, infrared, microwave, radio wave
What is the light carrying particle known as?
Photon
A fundamental limitation of a telescope's ability to resolve images, based on the
wave-like nature of light is known as _____.
Diffraction
What can be determined by the peak of a blackbody spectrum?
Peak indicates the temperature of the object
How would the blackbody spectrum of stars that are the same temperature differ
between a large and small star?
The peaks would be at the same location, since they are the same temperature, but
the peak would be higher for the larger star (more energy emitted per second)
