ASTRO 7N EXAM 2 INTRODUCTION TO
ASTRONOMY PRACTICE QUESTIONS AND
SOLUTIONS 2026 COMPLETE LEARNING
RESOURCE
◉ Where is the center of the Universe?
Answer: There is no center to the Universe. Expansion is happening
everywhere.
◉ How have astronomers interpreted the unexpectedly fast rotation
of galaxies?
Answer: There must be a lot of dark matter whose gravity can be felt
but not seen
◉ Which of the following is not true about dark matter?
Answer: Dark matter and dark energy are two aspects of the same
phenomenon
◉ Why do we think there is a lot of dark matter in clusters of
galaxies?
A) Individual galaxies are moving so fast that they could not be held
together by the gravity of visible matter
, B) We've detected some of its dark matter with telescope
C) The X rays seen coming from clusters of galaxies arise in very hot
clouds of gas
D) Gravitational lensing lets us measure mass even when we can't
see it
E) all answers except B
Answer: -Individual galaxies are moving so fast that they could not
be held together by the gravity of visible matter
-Gravitational lensing lets us measure mass even when we can't see
it (A&D)
◉ How do we know that the universe's expansion is speeding up?
Answer: We look at objects from different times in the past to see
how expansion changes with time
◉ How could the universe be accelerating, despite the gravitational
pull of all the matter in it?
Answer: There could be a new force or property of space that affects
the universe on its largest scales
◉ What fundamental particles makes up a Hydrogen-1 atom?
Answer: One proton, one electron
ASTRONOMY PRACTICE QUESTIONS AND
SOLUTIONS 2026 COMPLETE LEARNING
RESOURCE
◉ Where is the center of the Universe?
Answer: There is no center to the Universe. Expansion is happening
everywhere.
◉ How have astronomers interpreted the unexpectedly fast rotation
of galaxies?
Answer: There must be a lot of dark matter whose gravity can be felt
but not seen
◉ Which of the following is not true about dark matter?
Answer: Dark matter and dark energy are two aspects of the same
phenomenon
◉ Why do we think there is a lot of dark matter in clusters of
galaxies?
A) Individual galaxies are moving so fast that they could not be held
together by the gravity of visible matter
, B) We've detected some of its dark matter with telescope
C) The X rays seen coming from clusters of galaxies arise in very hot
clouds of gas
D) Gravitational lensing lets us measure mass even when we can't
see it
E) all answers except B
Answer: -Individual galaxies are moving so fast that they could not
be held together by the gravity of visible matter
-Gravitational lensing lets us measure mass even when we can't see
it (A&D)
◉ How do we know that the universe's expansion is speeding up?
Answer: We look at objects from different times in the past to see
how expansion changes with time
◉ How could the universe be accelerating, despite the gravitational
pull of all the matter in it?
Answer: There could be a new force or property of space that affects
the universe on its largest scales
◉ What fundamental particles makes up a Hydrogen-1 atom?
Answer: One proton, one electron
