ASTRO 101 ELITE STUDY GUIDE 2026
COMPREHENSIVE REVIEW WITH FULLY SOLVED
QUESTIONS AND DETAILED ANSWERS
◉What is a black hole? (Use gravity, curvature and light in answer)
Answer: A region of space where gravity is so strong that the curvature
of space-time stops light from escaping.
◉What is the event horizon around a black hole? Answer: The
boundary around a black hole where nothing including light will be able
to escape
◉What is melanoheliophobia? Answer: An irrational fear of black holes
◉True or False: A black hole and a star with the same mass and different
sizes have the same gravitational attraction from their centers. Answer:
True
◉True of False: Black holes and stars with the same mass and different
sizes have the same curvature of space-time. Answer: False, black holes
have a deeper curvature of space-time
◉What is the order of light in the EMS starting from radio? Answer:
Radio > Infrared > Visible > Ultraviolet > X-ray > Gamma
,◉True or Flase: X-rays have a longer wavelength than red visible light
Answer: False, X-rays have a higher frequency and shorter wavelength
than visible light
◉What is a photon? Answer: A particle of light. A small packet of
energy
◉What is wave-particle duality? Answer: Light can be considered a
wave or a particle depending on the situation.
◉What type of wave is light? Answer: A transverse wave
◉Another word for incandescence is Answer: Black body radiation
◉Another word for luminescence is Answer: Cold body radiation
◉How is incandescent light produced? Answer: heat energy and
particles vibrationg
◉What is the lowest temperature for incandescence to be produced and
why? Answer: 0 degrees since particles are still able to vibrate at this
temp
, ◉How is luminescent light produced? Answer: From atomic transitions.
Electrons jumping orbits
◉Florescence, phosphorescence and triboluminescence are examples of
what type of light production? Answer: Luminescence
◉What 3 properties describe light? Answer: Frequency, wavelength,
energy
◉What is an astronomical unit? Answer: The distance from the earth to
the sun
◉What is a light year Answer: The distance light travels in a year
◉What is a parsec? Answer: Unit of distance equal to 3.26 lightyears
◉What 2 things affect doppler shift? Answer: The emission of the
object and the relative speed of the object and the observer
◉When is an object red-shifted vs blue-shifted Answer: Red-shifted
objects are moving away from the observer. The wavelength behind the
object is stretched out. In a blue-shifted object, the wavelength is
compressed since the object is moving towards the observer
COMPREHENSIVE REVIEW WITH FULLY SOLVED
QUESTIONS AND DETAILED ANSWERS
◉What is a black hole? (Use gravity, curvature and light in answer)
Answer: A region of space where gravity is so strong that the curvature
of space-time stops light from escaping.
◉What is the event horizon around a black hole? Answer: The
boundary around a black hole where nothing including light will be able
to escape
◉What is melanoheliophobia? Answer: An irrational fear of black holes
◉True or False: A black hole and a star with the same mass and different
sizes have the same gravitational attraction from their centers. Answer:
True
◉True of False: Black holes and stars with the same mass and different
sizes have the same curvature of space-time. Answer: False, black holes
have a deeper curvature of space-time
◉What is the order of light in the EMS starting from radio? Answer:
Radio > Infrared > Visible > Ultraviolet > X-ray > Gamma
,◉True or Flase: X-rays have a longer wavelength than red visible light
Answer: False, X-rays have a higher frequency and shorter wavelength
than visible light
◉What is a photon? Answer: A particle of light. A small packet of
energy
◉What is wave-particle duality? Answer: Light can be considered a
wave or a particle depending on the situation.
◉What type of wave is light? Answer: A transverse wave
◉Another word for incandescence is Answer: Black body radiation
◉Another word for luminescence is Answer: Cold body radiation
◉How is incandescent light produced? Answer: heat energy and
particles vibrationg
◉What is the lowest temperature for incandescence to be produced and
why? Answer: 0 degrees since particles are still able to vibrate at this
temp
, ◉How is luminescent light produced? Answer: From atomic transitions.
Electrons jumping orbits
◉Florescence, phosphorescence and triboluminescence are examples of
what type of light production? Answer: Luminescence
◉What 3 properties describe light? Answer: Frequency, wavelength,
energy
◉What is an astronomical unit? Answer: The distance from the earth to
the sun
◉What is a light year Answer: The distance light travels in a year
◉What is a parsec? Answer: Unit of distance equal to 3.26 lightyears
◉What 2 things affect doppler shift? Answer: The emission of the
object and the relative speed of the object and the observer
◉When is an object red-shifted vs blue-shifted Answer: Red-shifted
objects are moving away from the observer. The wavelength behind the
object is stretched out. In a blue-shifted object, the wavelength is
compressed since the object is moving towards the observer
