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Supernova

A supernova is the explosive death of a star, during which it rapidly ejects most of its mass in a brilliant burst of light. In core‑collapse supernovae (Types Ib, Ic, II), massive stars (≥ 8 solar masses) exhaust their nuclear fuel, collapse under gravity, and explode. In Type Ia supernovae, a white dwarf in a binary system undergoes runaway fusion after accreting mass. These events deliver heavy elements into space, leave behind neutron stars or black holes, and power typical shock‑front supernova remnants.

Source: heasarc.gsfc.nasa.gov

APODs including "Supernova"

The Vela Supernova Remnant

02/06/2026

The Vela Supernova Remnant
Image Credit: José Mtanous / NASA APOD

The explosion is over, but the consequences continue. About twelve thousand years ago, a relatively normal star in the constellation Vela suddenly exploded, creating a strange point of light briefly visible to humans living near the beginning of recorded history. The outer layers of the star crashed into the interstellar medium, driving a shock wave that is still visible today. The featured image, taken piecemeal over 60 hours from the Khomas Region of Namibia, captures some of that filamentary and gigantic shock in visible light, with details highlighted by hydrogen (red) and oxygen (blue) emissions. As gas flies away from the detonated star, it decays and reacts with the interstellar medium, producing light in many different colors and energy bands. Remaining at the center of the Vela Supernova Remnant is a pulsar, a star as dense as nuclear matter that spins around more than ten times in a single second. Explore the Universe: Random APOD Generator