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New Worlds, New Horizons in Astronomy and Astrophysics
FIGURE 2.9 Solar Dynamics Observatory image of the Sun in the extreme ultraviolet. Different colors indicate different-temperature plasma, with hotter emissions traced from red to blue to green. SOURCE: NASA/SDO/AIA.
size of Earth. Mass transferred onto the white dwarf from its companion star can trigger a runaway thermonuclear instability and explosion, providing a light show that can be seen halfway across the universe. This type of supernova event is also the most important source of iron—from that in Earth’s core to the hemoglobin in our blood—in the universe.
Stars more massive than about 10 times the mass of the Sun end their lives as supernovae when their deep interior has exhausted all energy supplies from nuclear