Type Ia supernova
Quick Summary
A Type Ia supernova is a stellar explosion that occurs in binary systems. These systems typically involve a white dwarf star accreting matter from its companion star. When the white dwarf's mass exceeds the Chandrasekhar limit of about 1.4 solar masses, a thermonuclear explosion is triggered, destroying the white dwarf.123
Unlike other supernovae, Type Ia explosions do not show hydrogen lines in their spectra and expand much faster. These supernovae are valuable for astronomers because they all have a similar intrinsic luminosity, making them useful as "standard candles" to measure cosmic distances and study the expansion rate of the universe, including the discovery of dark energy.1
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Saul Perlmutter…1980s it became apparent that Type Ia supernovae would be better objects for determining distances to faraway galaxies. Beginning in 1988, Perlmutter began the Supernova Cosmology Project, which used large telescopes to search for supernovae. Perlmutter’s team found in 1998 that Type Ia supernovae that had exploded when the universe…
Read More…1980s it became apparent that Type Ia supernovae would be better objects for determining distances to faraway galaxies. Beginning in 1988, Perlmutter began the Supernova Cosmology Project, which used large telescopes to search for supernovae. Perlmutter’s team found in 1998 that Type Ia supernovae that had exploded when the universe…
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Adam RiessRiess’s work concentrated on using Type Ia supernovae to measure the expansion rate of the universe. In his doctoral thesis, he accounted for the effects of distance, luminosity, and extinction by intervening dust on how the light received from a Type Ia supernova changed with time. These calculations allowed these…
Read MoreRiess’s work concentrated on using Type Ia supernovae to measure the expansion rate of the universe. In his doctoral thesis, he accounted for the effects of distance, luminosity, and extinction by intervening dust on how the light received from a Type Ia supernova changed with time. These calculations allowed these…
Read More
Brian P. Schmidt…of astronomers that searched for Type Ia supernovae. Because these objects have roughly the same brightness, they can be used to accurately determine the distances to faraway galaxies and, thus, the expansion rate of the universe. Schmidt, Riess, and the team found in 1998 that Type Ia supernovae that exploded…
Read More…of astronomers that searched for Type Ia supernovae. Because these objects have roughly the same brightness, they can be used to accurately determine the distances to faraway galaxies and, thus, the expansion rate of the universe. Schmidt, Riess, and the team found in 1998 that Type Ia supernovae that exploded…
Read More