Supernova
Videos
A supernova is a powerful and luminous explosion of a star. A supernova occurs during the last evolutionary stages of a massive star, or when a white dwarf is triggered into runaway nuclear fusion. Th
SN 1994D (bright spot on the lower left), a Type Ia supernova within its host galaxy, NGC 4526
The Crab Nebula is a pulsar wind nebula associated with the 1054 supernova.
A 1414 text cites a 1055 report: since "the baleful star appeared, a full year has passed and until now its brilliance has not faded".
Supernova remnant SNR E0519-69.0 in the Large Magellanic Cloud
Stellar evolution
Videos
Stellar evolution is the process by which a star changes over the course of time. Depending on the mass of the star, its lifetime can range from a few million years for the most massive to trillions o
The violent youth of stars like the Sun
Artist's depiction of the life cycle of a Sun-like star, starting as a main-sequence star at lower left then expanding through the subgiant and giant phases, until its outer envelope is expelled to form a planetary nebula at upper right
The change in size with time of a Sun-like star
The Cat's Eye Nebula, a planetary nebula formed by the death of a star with about the same mass as the Sun