How are massive stars important contributors in enriching the galaxy with heavy elements?

How are massive stars important contributors in enriching the galaxy with heavy elements?

However, despite their relative low number, massive stars have a fundamental influence over the interstellar medium and galactic evolution because they are the responsible of the ionization of the surrounding gas and they deposit mechanical energy first via strong stellar winds and later as supernovae, enriching the …

Why is it that it takes a massive star to produce heavy elements?

A star’s energy comes from combining light elements into heavier elements in a process known as fusion, or “nuclear burning”. It is generally believed that most of the elements in the universe heavier than helium were created in stars when lighter nuclei fuse to make heavier nuclei.

Why can more massive stars fuse heavier elements?

However, in high mass stars, the temperature and pressure in the core can reach high enough values that carbon fusion can begin, and then oxygen fusion can begin, and then even heavier elements—like neon, magnesium, and silicon—can undergo fusion, continuing to power the star.

What changes in space result from the death of massive stars?

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.

What happens in a massive star?

In a massive star, hydrogen fusion in the core is followed by several other fusion reactions involving heavier elements. Just before it exhausts all sources of energy, a massive star has an iron core surrounded by shells of silicon, sulfur, oxygen, neon, carbon, helium, and hydrogen.

Why are the more massive stars the only important contributors in enrich?

Determine why only the most massive stars are important contributors in enriching the galaxy with heavy elements. A more massive star begins it’s life in the same way, with hydrogen being converted to helium, but it is much higher on the main sequence.

What is the evolution of a massive star?

Making New Elements in Massive Stars. Massive stars evolve in much the same way that the Sun does (but always more quickly)—up to the formation of a carbon-oxygen core. One difference is that for stars with more than about twice the mass of the Sun, helium begins fusion more gradually, rather than with a sudden flash.

Why are stars very massive?

In a massive star, the weight of the outer layers is sufficient to force the carbon core to contract until it becomes hot enough to fuse carbon into oxygen, neon, and magnesium. In really massive stars, some fusion stages toward the very end can take only months or even days!

Why are massive stars important to the universe?

While the universe started out filled with hydrogen and helium, stars are the factories that churn those light elements into almost every other element. When massive stars die an explosive death, they blow that material off, where it is gathered by other stars and formed into planets. Massive stars are also responsible for neutron stars.

What are the heavy elements in red giant stars?

This is the process at play in red giant stars, with more massive stars creating elements such as nitrogen, oxygen, neon, magnesium, silicon, sulphur, and iron-cobalt-and-nickel.

Are there any heavier elements in the universe?

Every element possible, that is, except the three we skipped. You see, the Universe starts off with hydrogen and helium, all stars produce helium, and then stars over a certain mass threshold produce carbon, nitrogen, oxygen and lots of heavier elements.

Why did the heaviest stars die first in the universe?

Over time, we expect that the interstellar medium, which is where the gas that gives rise to stars originates, gets more and more enriched by new generations of stars that live-and-die, with the heaviest-mass stars dying first.