Which of these can a star become at the end of its evolution? Choose the three correct answers.
a black hole
a supernova
a neutron star
a white dwarf
a brown dwarf
The three correct answers are:
1. A black hole: This is formed when a massive star collapses under its own gravitational force and forms a singularity, creating a region of spacetime with extreme gravitational attraction that nothing, not even light, can escape from.
2. A supernova: This occurs when a massive star undergoes a catastrophic explosion, expelling a vast amount of its material into space. The explosion releases an immense amount of energy, making the star briefly shine brighter than an entire galaxy.
3. A neutron star: This is formed when a massive star undergoes a supernova explosion and collapses, but not enough to form a black hole. The collapse results in a highly dense object composed primarily of neutrons, with a strong gravitational field.
A white dwarf and a brown dwarf are not outcomes of stellar evolution. A white dwarf is the hot, dense leftover core of a low or medium mass star after it has exhausted its nuclear fuel, while a brown dwarf is an object that is too small to sustain nuclear fusion and does not become a star.
A star can become the following at the end of its evolution:
1. A supernova: This is the explosive event that occurs when a massive star runs out of nuclear fuel and collapses under its own gravity, causing a powerful explosion.
2. A white dwarf: When a star exhausts its nuclear fuel and is not massive enough to undergo a supernova, it can shrink and become a dense, hot object known as a white dwarf. White dwarfs are typically about the size of Earth but contain a mass comparable to that of the sun.
3. A neutron star: Neutron stars are formed when a massive star undergoes a supernova and its core collapses under gravitational forces. The core is compressed to extreme densities, with protons and electrons combining to form neutrons. Neutron stars are incredibly dense and have strong magnetic fields.
A star cannot become a black hole, brown dwarf, or any other celestial object listed.