Stars Dying, Type I, Type II Supernovae


Stars Dying, Type I, Type II Supernovae


Question 1

Various steps follow the demise of stars of low stellar mass, medium stellar as well as those that are very massive. First, for the low mass star, the helium fusion leads to the formation of carbon core. The carbon core collapses but at a low temperature not enough to allow fusion of carbon. The outer region of the shell expands while the helium and hydrogen die out. This eventually contributes to the ejection of the outer region of the star into space. The ejection occurs in the form of a cloud. Lastly, the core region of the star cools down in order to form a white dwarf (Stevenson, 2015).

Secondly, the fate of the massive stars is very dramatic. Over time, the star swells into a supergiant, the core generates gravity and shrinking process starts. The shrinking makes the star hotter and denser. Eventually, the fusion process ceases since the star becomes iron. The final phase of gravitational collapse starts to occur with the temperature of the core, and increases to over 100 billion degrees. The coil recoils out from the star in an extreme moreover explosive shock wave. The shock encounters the star outer layers heating them to form radioactive isotopes. The shock pushes materials outside the star in an explosion called a supernova. Only the core of the original star remains. However, the neutrons do not survive and black hole forms (Stevenson, 2015).

Lastly, when the medium sized star ages, its outer layer expands while the core contracts inwards. The contraction causes the fusion of the helium atoms, particularly in the core region to form carbon. The fusion releases energy that gives the star a reprieve. After that, the star begins to shed the outer layers in the form of cloud known as a planetary nebula. At this point, the star sheds about 80% of the star initial mass. The remaining mass starts to cool moreover shrink until its diameter is few thousand miles. At this point, the star becomes a white dwarf. The white dwarf radiates the remaining heat in space. Eventually, it becomes a cold mass sitting in the space known as a black dwarf (Stevenson, 2015).
Question 2

The supernova is the volatile death of a star. It results to high brightness of more than 100 million times for a short while. The Type I occurs in the dual star systems. In the case, one star emits the gas that falls on a white dwarf causing an explosion. The white dwarf is subject to degeneration. The process occurs only to star mass less than 1.4 times the sun. The dual starts losses momentum until they become close together. The move causes transfer of the matter to the companion star to the thick lining around the white dwarf. Therefore, the mass of the white dwarf increases to a value higher than the critical value. Eventually, the star collapses leading to burning of carbon and oxygen by the nuclear energy. The burning generates enough energy to blow the star into bits (Stevenson, 2013).

Alternatively, type II occurs in massive stars than the sun. The star suffers internal nuclear reactions at their demise leading to an explosion. The explosion leaves black holes and neutron stars. The hydrogen becomes exhausted and burning occurs only at the shell around the helium core. The burning occurs due to the gravity contraction. The burning phase lasts for million years. The helium burns into carbon and oxygen. Furthermore, the contraction causes the conversion of carbon into neon and magnesium then to silicon and finally to iron. The iron cannot further emit energy hence no radiation pressure to match the gravitational force. Eventually, a shock wave occurs that leads to an explosion. The explosion expels the planetary material into the space leading to supernova (Stevenson, 2013).


Stevenson, D. S. (2013). Extreme explosions: Supernovae, Hypernovae, Magnetars, And Other Unusual Cosmic Blasts. New York: Springer.
Stevenson, D. S. (2015). The Complex Lives of Star Clusters. Cham: Springer.

Order 62271: Stars dying, Type I ,Type II supernovae


Did it help you?

Cite this Page

Stars Dying, Type I, Type II Supernovae. (2022, Jan 31). Retrieved from

Need customer essay sample written special for your assignment?

Choose skilled expert on your subject and get original paper with free plagiarism report

Order custom paper

Without paying upfront