CNSL 503 EXAM MODULE 7 CORRELATIONAL
ANALYSIS AND LINEAR REGRESSION
COMPREHENSIVE STUDY GUIDE
◉ The _____ is the cycling of mass in and out of the interstellar
medium, including accretion of gas from intergalactic space, loss of
gas back into intergalactic space, and conversion of interstellar gas
into stars
Answer: Baryon cycle
◉ Among interstellar clouds, the hotter the cloud, the
Answer: the lower the density of particles in it
◉ Astronomers studying regions like the Orion Giant Molecular
Cloud have observed that a wave of star formation can move through
them over many millions of years. What sustains such a wave of star
formation in a giant molecular cloud?
Answer: when massive stars form, their ultraviolet radiation and
later their final explosions compress the gas in the cloud and cause a
new group of stars to form
◉ A _____ is a very young star still in the process of formation, before
nuclear fusion begins
,Answer: Protostar
◉ Which of the following is not a place where astronomers believe
interstellar dust grains can form?
Answer: in H II regions
◉ The _____ is the region of ionized hydrogen in interstellar space
Answer: H II region
◉ _____ is an empirical relation between the periods and luminosities
of certain variable stars
Answer: period-luminosity relation
◉ The first (living) star other than our own Sun found to have more
than one planet orbiting it is called
Answer: Upsilon Andromedae
◉ How do astronomers know that pulsating variable stars are
actually expanding and contracting in diameter?
Answer: they can measure a regularly varying Doppler shift in the
spectral lines
, ◉ Supposing we launched a very fast dart from the Space Shuttle,
pointed in some direction away from any planet, so that it could
travel beyond the solar system. What would it be most likely to hit
first after traveling outward for a while?
Answer: an atom of interstellar gas
◉ What is the baseline that astronomers use to measure the parallax
(the distance) of the nearest stars?
Answer: ½ the diameter of the Earth's orbit around the Sun
◉ If an astronomer wants to find the distance to a star that is not
variable and is located too far away for parallax measurements, she
can:
Answer: find the star's luminosity class from its spectrum and read
the luminosity from an H-R diagram
◉ An astronomer is observing a single star (and one which does not
vary) which she knows is located about 30 light-years away. What
was the most likely method she or her colleagues used to obtain that
distance?
Answer: measuring the star's parallax
◉ An astronomer wants to observe a cloud of dust in a relatively
close part of the Galaxy. Unfortunately, this dust cloud is not located
ANALYSIS AND LINEAR REGRESSION
COMPREHENSIVE STUDY GUIDE
◉ The _____ is the cycling of mass in and out of the interstellar
medium, including accretion of gas from intergalactic space, loss of
gas back into intergalactic space, and conversion of interstellar gas
into stars
Answer: Baryon cycle
◉ Among interstellar clouds, the hotter the cloud, the
Answer: the lower the density of particles in it
◉ Astronomers studying regions like the Orion Giant Molecular
Cloud have observed that a wave of star formation can move through
them over many millions of years. What sustains such a wave of star
formation in a giant molecular cloud?
Answer: when massive stars form, their ultraviolet radiation and
later their final explosions compress the gas in the cloud and cause a
new group of stars to form
◉ A _____ is a very young star still in the process of formation, before
nuclear fusion begins
,Answer: Protostar
◉ Which of the following is not a place where astronomers believe
interstellar dust grains can form?
Answer: in H II regions
◉ The _____ is the region of ionized hydrogen in interstellar space
Answer: H II region
◉ _____ is an empirical relation between the periods and luminosities
of certain variable stars
Answer: period-luminosity relation
◉ The first (living) star other than our own Sun found to have more
than one planet orbiting it is called
Answer: Upsilon Andromedae
◉ How do astronomers know that pulsating variable stars are
actually expanding and contracting in diameter?
Answer: they can measure a regularly varying Doppler shift in the
spectral lines
, ◉ Supposing we launched a very fast dart from the Space Shuttle,
pointed in some direction away from any planet, so that it could
travel beyond the solar system. What would it be most likely to hit
first after traveling outward for a while?
Answer: an atom of interstellar gas
◉ What is the baseline that astronomers use to measure the parallax
(the distance) of the nearest stars?
Answer: ½ the diameter of the Earth's orbit around the Sun
◉ If an astronomer wants to find the distance to a star that is not
variable and is located too far away for parallax measurements, she
can:
Answer: find the star's luminosity class from its spectrum and read
the luminosity from an H-R diagram
◉ An astronomer is observing a single star (and one which does not
vary) which she knows is located about 30 light-years away. What
was the most likely method she or her colleagues used to obtain that
distance?
Answer: measuring the star's parallax
◉ An astronomer wants to observe a cloud of dust in a relatively
close part of the Galaxy. Unfortunately, this dust cloud is not located
