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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"

NGC 3660 and Burçin's Galaxy

26/05/2026

NGC 3660 and Burçin's Galaxy
Image Credit: Adam Block, El Sauce Obs. / NASA APOD

The upper galaxy might be more photogenic, but the lower galaxy is more unusual. The galaxy up top is NGC 3660, a spiral galaxy similar to our own Milky Way galaxy in that it has several bright blue spiral arms and a central bar of stars, dust, and gas. Captured by chance in the featured deep and colorful image, surprisingly, is SN 2026cff, a supernova found just to the right of the central bar. Farther in the distance is the bottom galaxy, known informally as Burçin’s galaxy, but formally cataloged as LEDA 1000714. The center of this galaxy appears to be an old elliptical galaxy, but it is strangely surrounded by not one but two rings of stars. What created Burçin's galaxy is a mystery and remains a continuing topic of research, but it likely involves the accretion of one or more smaller galaxies.