unit 5 part 1 science
About how long will a star with a mass about the same as our sun's mass stay on the main sequence?
10 billion years
According to the Big Bang theory, during the formation and expansion of the universe, hydrogen and helium were produced. How are the elements that are heavier than helium but lighter than or equal to iron produced?
Elements heavier than helium but lighter than or equal to iron are produced by nuclear fusion within stars.
What happens when hydrogen nuclei fuse into helium nuclei in the sun?
Energy is released.
An astronomer observes the chemical composition of two stars with similar masses. She records the following data. Based on these observations
Star A is likely older because more of its hydrogen has undergone nuclear fusion to become helium.
Which statement accurately relates a star's mass to its expected life cycle?
Stars with a greater mass conduct fusion at a faster rate, which leads to a shorter lifespan as a main-sequence star.
Energy is released from the sun and ultimately reaches Earth. Analyze the graph of solar irradiance. Which explanation could describe why the amount of energy that reaches Earth is not consistent?
Sunspots release energy in an 11-year cycle because of the magnetic field of the sun.
Astronomers studying the light spectrum lines of light coming from the nearby Andromeda galaxy noticed that it is blue shifted. What does the blue shift of light coming from the Andromeda galaxy imply about its motion relative to Earth, and what implications does this have on the Big Bang theory
The Big Bang theory predicts that most but not all galaxies are moving away from each other. The blue shift indicates that the Andromeda galaxy is one of the few galaxies moving toward Earth.
Which statement correctly describes the relationship between the amount of hydrogen and the amount of time that a star produces helium and energy?
The more hydrogen a star has at the beginning of its life, the less time it will make helium and energy because hydrogen is a limiting factor in the fusion reaction that produces helium and energy.
If a dense, non-light producing, interstellar gas were to move between a star and Earth, what would happen to the spectra of the light from the star as measured on Earth?
The number of absorption lines would likely increase.
A student states that the less hydrogen a star has at the beginning of life, the longer it will make helium. Which of these explains whether the student's statement is accurate or not? *
The student's statement is inaccurate. Hydrogen converts to helium through the process of fusion. It is not possible to have less hydrogen but more helium early in life.
Which statement describes objects such as stars that are moving toward an observer?
They display a blue shift.
The diagram depicts the life cycle of a star. All matter in the universe can be linked to this process. Which statement explains the origin of the elements heavier than iron in the universe?
When the iron core of a red supergiant collapses in on itself to form a supernova, a large amount of heat is generated, which provides the energy needed to form these heavy elements.
What are particles thrown off the sun's corona that can affect Earth's magnetic field called?
a coronal mass ejection
What will our sun become when it runs out of fuel?
a red giant
In what part of the sun is matter converted into energy?
core
In which type of star is the element iron most likely to develop?
hotter, more massive star
What Doppler shift would an astronomer notice for the spectral light from a galaxy moving away from Earth?
lower frequency and longer wavelengths
What are constellations?
recognizable patterns of stars and the regions of space around them
What can astronomers determine by analyzing the light a star emits?
the composition and temperature of the star
What is fueling the production of energy in Alpha Centauri A?
the fusion of hydrogen to helium
