Vocabulary
A large collection of stars, gas, and dust that is held together by gravity.
Galaxy
What is a large celestial body that is composed of gas and emits light?
Star
What is the standard unit that astronomers use to measure the size of stars?
solar radius
Where do stars form?
Stars form in nebulae. A nebula is a large cloud of gas and dust.
Give the full name of the person that discussed about black holes
Peggy Norris
It is a measure of how bright a star would be if the star were located at a standard distance.
Absolute magnitude
How does the composition of a star differ from the composition of a planet?
Planets are either rocky or made of gas and rock; stars, by comparison, are composed of hot gases.
What is the surface temperature of the sun?
5,527 degrees Celsius
What process begins when a star is born?
Hydrogen fusion
Sanford Underground Research Facility in Lead, SD
It is the hot, dense core of matter that remains from the collapse of a low-mass star.
White dwarf
What makes up our solar system?
the sun, planets, moons, dwarf planets, comets, asteroids, and meteoroids
What is the surface temperature of a blue star?
Above 25,000 degrees Celsius
How do astronomers measure the brightness of a star?
Apparent magnitude is the measure of a star’s brightness as seen from Earth.
What is the center of the universe?
Black hole
Astronomers use this word to refer the star's actual brightness.
Luminosity
Define light year, and explain how and why light years are used to measure distances in the universe.
A light year is the distance that light travels through space in 1 year or 9.5 trillion km. Distances in space are so large that smaller measurements such as kilometers are insufficient to measure these distances.
Why will the color of the sun change from yellow to red when it becomes a giant?
The color change is caused by a change in temperature. The sun will become cooler when it becomes a giant.
What causes a supernova?
The core of a supergiant rapidly collapses. The core heats up, causing the collapse to halt. The star explodes, throwing its outer layers into space.
Where do black holes come from?
From dying stars
It is the region of the diagram where stars spend most of their lives. Stars within this band are actively fusing hydrogen.
Main sequence
Why can the structure of the universe be compared to soap bubbles?
The universe is made up of "walls" of densely concentrated galaxies that surround large spherical voids.
Describe how the life cycle of a low-star mass differs from the life cycle of a high-mass star?
Low-mass stars remain in the main sequence for a longer time than high-mass stars do. Low-mass stars become giants and end their lives as white dwarfs. High-mass stars become super giants that supernovae and end their lives as neutron stars or black holes.
What are some of the physical properties of stars?
apparent magnitude, absolute magnitude, color ad surface temperature, size
What does LIGO stand for? Where is it located?
Laser Interferometry Gravitational Observatory @ Hanford, Washington