What is the net effect of the star-gas-star cycle?
C) There is no net effect to the cycle. Mass in the interstellar medium lost to star formation is exactly replaced by stellar winds and supernova explosions. We can see most of the Milky Way with visible light.
What is the star gas cycle?
The star – gas cycle in galaxies. Efremov et al. (1999). The hot gas enhances the metalicity of the galactic halo and forms the galactic fountains that return the gas to the galactic plane as high velocity clouds.
What happens after many generations of the star-gas-star cycle?
What happens after many generations of the star-gas-star cycle? hydrogen gas decreases.
What is the primary way in which high mass stars recycle material into the interstellar medium?
The material of stars is recycled over billions of years. Interstellar gas clouds collapse to make stars. Stars forge heavy elements and return their gas to space. This material enriches gas clouds from which new stars are formed, and the cycle continues.
How is gas recycled in our galaxy?
Supernova blast waves expand into interstellar space. Elements made in stars are mixed back into the gas. Bubbles blown by high-mass stars burst out of the disk. The gas cools and falls back into the galaxy.
What places a limit on the lifetime of a star?
What places a limit on the lifetime of a star? core hydrogen fusion.
What are the steps of a star life cycle?
Seven Main Stages of a Star
- Giant Gas Cloud. A star originates from a large cloud of gas. …
- Protostar. When the gas particles in the molecular cloud run into each other, heat energy is produced. …
- T-Tauri Phase. …
- Main Sequence. …
- Red Giant. …
- The Fusion of Heavier Elements. …
- Supernovae and Planetary Nebulae.
How would you expect a star that formed recently in the disk of the galaxy to differ from one that formed early in the history of the disk?
How would you expect a star that formed recently in the disk of the galaxy to differ from one that formed early in the history of the disk? It should have a higher fraction of elements heavier than hydrogen and helium.
Why has star formation ceased in the galactic halo?
Why has star formation ceased in the galactic halo? All of the galaxy's cool gas settled to the galactic plane long ago.
What is the galactic recycling process?
We now know they are surrounded by a much larger, yet nearly invisible cloud of dust and gas. Astronomers call it the circumgalactic medium, or CGM. The CGM acts as a giant recycling plant, absorbing matter ejected by the galaxy and later pushing it right back in.
What effect does the star gas star cycle have on the amount of heavy elements?
With each cycle, more heavy elements are made by nuclear fusion in stars. Recycles gas from old stars into new stars. With each cycle, more heavy elements are made by nuclear fusion in stars.
How is gas recycled in our galaxy quizlet?
how is gas recycled in our galaxy? –low mass stars return gas to interstellar space through stellar winds and planetary nebulae. -High-mass stars have strong stellar winds that blow bubbles of hot gas. -High mass stars explode in supernovae and spread newly made heavy elements into the interstellar medium.
How do galaxies recycle stars?
Gravity, pulling gases from the CGM towards the galactic center, injects galaxies with fresh fuel for making stars. At the same time, stellar winds and supernova shoot metals back into the CGM, replenishing the supply.
What is the lifetime of a star?
The most massive stars live for a cosmically brief hundreds of millions of years. They live fast and die young. The smallest stars that are less than about 10% of the sun's mass have far less fuel to begin with; even so, they can eke out a living from their fuel supply for hundreds of billions of years.
What happens to a star when it runs out of fuel?
When a main sequence star begins to run out of hydrogen fuel, the star becomes a red giant or a red super giant. THE DEATH OF A LOW OR MEDIUM MASS STAR After a low or medium mass or star has become a red giant the outer parts grow bigger and drift into space, forming a cloud of gas called a planetary nebula.
How long is a stars life cycle?
Scientific Background for Life Cycle of Stars. Go back to Lesson. Because stellar lifetimes range from perhaps 40,000 years to longer than 10 billion years, astronomers never get to watch a particular star go through all of its life cycle phases.
When stars begin to run out of fuel they first become?
When a main sequence star begins to run out of hydrogen fuel, the star becomes a red giant or a red supergiant. After a low- or medium-mass star has become a red giant, the outer parts grow bigger and drift into space, forming a cloud of gas called a planetary nebula.
When we talk about the star gas star cycle we are describing the?
What do we mean by the star-gas-star cycle? It is the continuous recycling of gas in the galactic disk between stars and the interstellar medium.
Why do disk stars bob up and down as they orbit the galaxy quizlet?
What are basic characteristics of stars' orbits in the disk, halo, and bulge of our galaxy? The disk stars have nearly circular orbits. They have vertical motions out of the plane, making them appear to bob up and down, but they never get "too far" from the disk.
What is the galactic halo quizlet?
Galactic halo. Region of a galaxy extending far above and below the galactic disk, where globular clusters and other old stars reside. – Roughly spherical- mildly flattened. – Contains old stars only. – contains no gas and dust.
What is halo of galaxy?
galactic halo, in astronomy, nearly spherical volume of thinly scattered stars, globular clusters of stars, and tenuous gas observed surrounding spiral galaxies, including the Milky Way—the galaxy in which the Earth is located.
Will galactic recycling continue forever?
The infalling gas from this vast reservoir fuels the Milky Way with the equivalent of about a solar mass per year, which is comparable to the rate at which our galaxy makes stars. At this rate the Milky Way will continue making stars for another billion years by recycling gas into the halo and back onto the galaxy.
Why do stars expand as they age?
Later, as the preponderance of atoms at the core becomes helium, stars like the Sun begin to fuse hydrogen along a spherical shell surrounding the core. This process causes the star to gradually grow in size, passing through the subgiant stage until it reaches the red-giant phase.
How did our galaxy form quizlet?
How did our galaxy form? Our galaxy formed from a cloud of intergalactic gas. Halo stars formed first as gravity caused gas to contract. Remaining gas settled into a spinning disk.
Do stars last forever?
Answer: No. Stars are born, live, and die. This process is called the "life cycle of a star".
How long is a star’s life cycle?
The most massive stars live for a cosmically brief hundreds of millions of years. They live fast and die young. The smallest stars that are less than about 10% of the sun's mass have far less fuel to begin with; even so, they can eke out a living from their fuel supply for hundreds of billions of years.
How do stars end their life cycle?
With no fuel left to burn, the hot star radiates its remaining heat into the coldness of space for many billions of years. In the end, it will just sit in space as a cold dark mass sometimes referred to as a black dwarf.
What happens to a star after it dies?
When the helium fuel runs out, the core will expand and cool. The upper layers will expand and eject material that will collect around the dying star to form a planetary nebula. Finally, the core will cool into a white dwarf and then eventually into a black dwarf. This entire process will take a few billion years.
What does life cycle of a stars mean?
A star's life cycle is determined by its mass. The larger its mass, the shorter its life cycle. A star's mass is determined by the amount of matter that is available in its nebula, the giant cloud of gas and dust from which it was born.
What happens in each stage of the life cycle of a star?
Smaller stars use up fuel more slowly so will shine for several billion years. Eventually, the hydrogen which powers the nuclear reactions inside a star begins to run out. The star then enters the final phases of its lifetime. All stars will expand, cool and change colour to become a red giant.