# Wolfram Data Repository

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Supernova type Ia name, redshift, magnitude, stretch and color

The redshift z of an object is defined as z=(*λ*_{obs}-*λ*_{0})/*λ*_{0} where *λ*_{obs} is the observed wavelength and *λ*_{0} is the emitted wavelength. When z>0 then the object is redshifted and is receding from the observer. In general larger values of redshift correspond to objects that are more distant.

The observed magnitude m of an an object is a reverse logarithmic measure of the flux from the object for an observer on earth. If F is the measured flux and F_{ref} is a reference flux then the magnitude is m=-2.5log_{10}(F/F_{ref}). Faint objects have larger magnitudes than bright objects.

Stretch is a measure of how fast the supernova explosion declines in brightness. Color is the B-V color at peak brightness.

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Obtain the necessary data:

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Plot observed magnitude of supernova versus redshift:

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Marshall Bradley, "Type Ia Supernova Data" from the Wolfram Data Repository (2022)