Stellar population refers to the collection of stars in a galaxy, characterized by their age, metallicity, and other properties.

The Hubble constant is a constant that relates the distance to a galaxy to its recessional velocity, indicating the expansion of the universe.

Star formation is the process by which dense regions of gas and dust in interstellar clouds collapse and form stars.

A neutron star is a collapsed core of a massive star that has undergone a supernova, consisting primarily of neutrons.

The event horizon is the boundary around a black hole beyond which nothing, including light, can escape due to the immense gravitational pull.

Stellar evolution refers to the various stages a star goes through during its lifetime, including the red giant phase and eventually becoming a white dwarf.

The singularity is the point at the center of a black hole where gravity is infinitely strong and space-time is distorted.

A supernova is a violent explosion that occurs at the end of the life of a massive star, releasing enormous amounts of energy and matter.

The habitable zone is the region around a star where conditions are suitable for liquid water to exist on the surface of a planet.

Stellar merger is the process by which two or more stars collide and combine to form a single, larger star.

Large-scale structure refers to the distribution and arrangement of galaxies, galaxy clusters, and superclusters in the universe.

The red giant phase is a stage in the life of a star where it expands and becomes cooler, consuming its hydrogen fuel.

The ergosphere is the region of space around a black hole where objects can be dragged along by the black hole's rotation.

A planetary nebula is a glowing shell of gas and dust ejected by a star during the final stages of its life.

Black hole formation occurs when a massive star collapses under its own gravity, creating a region of spacetime where gravity is so strong that nothing, not even light, can escape.