What are the typical values of gas fraction (gas to stellar mass) in a spiral galaxy as a function of Hubble type? -Space

What are the typical values of gas fraction (gas to stellar mass) in a spiral galaxy as a function of Hubble type? -Space
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1 Answer

Answer :

We show that the gas mass fraction of spiral galaxies is strongly correlated with luminosity and surface brightness. It is not correlated with linear size. Gas fraction varies with luminosity and surface brightness at the same rate, indicating evolution at fixed size.      Dim galaxies are clearly less evolved than bright ones, having consumed only  of their gas. This resolves the gas consumption paradox, since there exist many galaxies with large gas reservoirs. These gas-rich galaxies must have formed the bulk of their stellar populations in the last half of a Hubble time. The existence of such immature galaxies at z = 0 indicates that either galaxy formation is a lengthy or even ongoing process, or the onset of significant star formation can be delayed for arbitrary periods in tenuous gas disks.
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Related questions

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Description : Has the quantity of stellar mass of the Milky Way changed much since its formation? -Space

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Think of this: space?

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he first space rocket brought back to earth after orbiting the moon -Space

Description : he first space rocket brought back to earth after orbiting the moon -Space

Last Answer : Zond-5 is the right answer

The first unmanned moon buggy to explore surface of the moon -Space

Description : The first unmanned moon buggy to explore surface of the moon -Space

Last Answer : Lunakhod-1 (U.S.S.R.) is

The first space-vehicle to orbit the moon -Space

Description : The first space-vehicle to orbit the moon -Space

Last Answer : Luna-10 (U.S.S.R.) is answer

The first country to send man to the moon -Space

Description : The first country to send man to the moon -Space

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The first spaceship which carried three American astronauts to land two of them on the moon -Space

Description : The first spaceship which carried three American astronauts to land two of them on the moon -Space

Last Answer : The Apollo 11 Command Module Columbia carried astronauts Neil Armstrong, Edwin "Buzz" Aldrin, and Michael Collins on their historic voyage to the Moon and back on July 16-24, 1969. During the mission, astronauts Armstrong and Aldrin became the first human explorers of another world.

The first manned space vehicle to land on the moon -Space

Description : The first manned space vehicle to land on the moon -Space

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Description : The first unmanned spaceship to have soft landed and lifted off from the moon to return to the earth -Space

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Description : The first woman cosmonaut of the world -Space

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