Stars and Galaxies

Front

What is a black hole?

Back

A black hole is a region in space where the gravitational pull is so strong that nothing, not even light, can escape from it. It is formed when a massive star collapses under its own gravity after a supernova.

Front

What is the main element in a star's composition?

Back

Hydrogen is the main element in a star's composition, making up about 74% of the universe's elemental mass.

Front

What is a white dwarf?

Back

A white dwarf is the remnant core of a low-mass star that has exhausted its nuclear fuel and shed its outer layers. It is very dense and no longer undergoes fusion.

Front

What happens to very massive stars after they exhaust their nuclear fuel?

Back

Very massive stars collapse into black holes after they exhaust their nuclear fuel and undergo a supernova explosion.

Front

How old is the universe?

Back

The universe is approximately 13.7 billion years old.

Front

What is a neutron star?

Back

A neutron star is the remnant core of a massive star that has undergone a supernova explosion, consisting mostly of neutrons and is incredibly dense.

Front

What is a supernova?

Back

A supernova is a powerful and luminous explosion that occurs at the end of a massive star's life cycle, often resulting in the formation of a neutron star or black hole.

Front

What is the difference between a black hole and a neutron star?

Back

A black hole is a region of space with a gravitational pull so strong that nothing can escape, while a neutron star is a dense remnant of a supernova, composed mostly of neutrons.

Front

What is the life cycle of a low-mass star?

Back

A low-mass star evolves from a protostar to a main sequence star, then to a red giant, and finally collapses into a white dwarf.

Front

What is the life cycle of a massive star?

Back

A massive star evolves from a protostar to a main sequence star, then to a red supergiant, and finally undergoes a supernova, potentially becoming a neutron star or black hole.