Stars

Question 1

Solar Nebula

Answer 1

a gaseous cloud, a giant cloud of dust and gas in space

Question 2

Hertzsprung-Russell Diagram

Answer 2

illustrates the relationship between the absolute magnitude and the surface temperature of stars

Question 3

White dwarf

Answer 3

a small, hot dim star that is the leftover center of an old star

Question 4

Luminosity

Answer 4

the total amount of energy a star gives off each second

Question 5

Nuclear fusion

Answer 5

a process that occurs when extremely high temperature and pressure cause less-massive atomic nuclei to combine to form more-massive nuclei and release enormous amounts of energy

Question 6

Absolute magnitude

Answer 6

the brightness of a star if it were seen from a standard distance

Question 7

Supernova

Answer 7

a star that has such a tremendous explosion that it blows itself apart

Question 8

Apparent magnitude

Answer 8

brightness of a star as seen from Earth

Question 9

Black hole

Answer 9

an object so massive and dense that even light cannot escape its gravity

Question 10

Galaxy

Answer 10

a collection of stars, dust and gas bound together by gravity

Question 11

Planetary Nebula

Answer 11

a cloud of gas that forms around a sun-like star that is dying

Question 12

Protostar

Answer 12

shrinking, spinning region that begins to flatten into a disk that has a central concentration of matter

Question 13

Star

Answer 13

a ball of gases that gives off a tremendous amount of electromagnetic energy. This energy comes from nuclear fusion.

Question 14

Main-sequence star

Answer 14

about 90% of stars, they fuse hydrogen atoms to form helium atoms in their cores

Question 15

Neutron Star

Answer 15

a star that has collapsed under gravity to the point that the electrons and protons have smashed together to form neutrons

Question 16

Identify the major factor that controls a star’s evolution and lifespan.

Answer 16

the total mass

Question 17

List the two major elements found in stars

Answer 17

hydrogen + helium

Question 18

During the beginning of a star’s life in nuclear fusion what element is created

Answer 18

helium

Question 19

Describe what is happening during the stellar nebula stage.

Answer 19

In the stellar nebula stage, a cloud of gas and dust is where a star begins. The gravitational force increases as the mass of an object increases or as the distance between two objects decreases. As more particles come together, regions of dense matter begin to build up within the cloud. Depending on the amount of gas and dust, the star may become massive or average. That defines the two evolution of stars.

Question 20

Identify when the birth of a star begins

Answer 20

Onset of fusion

Question 21

Explain what is happening during the main sequence stage of a star.

Answer 21

Nuclear fusion occurs faster in more massive stars than less massive stars and hydrogen is fused into helium. When this happens, the star begins to move out of the main-sequence stage and about 90% of the stars are main sequence stars.

Question 22

Explain why stars leave the main sequence stage.

Answer 22

Stars start to lose their main fuel, hydrogen, depending on their initial mass. The loss of energy causes the main sequence’s gravitational collapse to resume.

Question 23

Define nuclear fusion.

Answer 23

A process that occurs when extremely high temperature and pressure cause less-massive atomic nuclei to combine to form more-massive nuclei an in this process, release enormous amounts of energy.

Question 24

Explain what happens to helium and the outer layers of a star in the planetary nebula stage

Answer 24

The star’s outer layers continue to expand, the core contracts inward, and helium atoms in the core fuse together to form carbon. The star will now begin to shed its outer layers as a diffuse cloud.

Question 25

Why do stars become giants or supergiants?

Answer 25

The fusion of hydrogen to form helium changes the interior composition of a star, which turn results in changes in its temperature, luminosity, and radius.

Question 26

What is a supernova?

Answer 26

A supernova is the big luminous explosion of a star.

Question 27

What happens to the star after a supernova?

Answer 27

It becomes a neutron star

Question 28

What is a white dwarf?

Answer 28

A white dwarf is a small, dim star that is the leftover center of an old star. Hot, extremely dense core of matter. Gravity causes the remaining matter in the star to collapse inward. The matter collapses until it cannot be pressed further together.

Question 29

List the star’s color in the correct order from hottest to coldest.

Answer 29

Blue, white, yellow, orange, red

Question 30

Identify the 3 types of galaxies. What galaxy is Earth in?

Answer 30

Elliptical galaxy, irregular galaxy, spiral galaxy, milky way galaxy (the one earth is in)

Question 31

Identify the two variables used to identify stars on the H-R diagram.

Answer 31

Luminosity and temperature

Question 32

Identify the 4 major classifications of stars.

Answer 32

Main sequence, blue giants, red supergiants, red giants

Question 33

Differentiate between a red giants and blue giants

Answer 33

Blue giant: they are younger, higher temperature, eventually becomes a red giant, burns mostly hydrogen
Red giant: older, lower temperature, may become a blue giant if its core gets hot enough and the outer gases escape, burns helium

Question 34

List the average star’s stages in correct order.

Answer 34

Stellar nebula, Birth of a star, Main sequence, Giant star, Planetary nebula, White dwarf

Question 35

List the massive star’s stages in correct order.

Answer 35

Stellar nebula, Birth of a Star, Main sequence, Super Giant star, Supernova, Black hole/neutron star

Question 36

Scientists believe that the Solar Nebula Theory is the best theory that is used to describe how our solar system was formed. In one paragraph explain this theory.

Answer 36

A cloud of gas and dust began to collapse by gravity begins to spin faster because of the angular momentum conservation. The collapsing, spinning nebula begins to flatten into a pancake shape with a bulge at the center. As the nebular collapses further, rotating cloud cause local regions to begin to contract gravitationally. These regions become the sun and the planets as well as moon and others in the solar system.