Index

The Origin of the Universe

A survey of the evidence

Introduction
Measurement Overview
    Parallax Distances
    Star Sizes and Absolute Magnitudes
    Cepheid Distances
    Type 1a Supernovae Distances
    Redshift Velocities and Distances
    Age of the Stars in Globular Clusters
    The Oldest White Dwarfs
    The Cosmic Microwave Background
Conclusion

Cepheid Distances

Among the stars for which we have precise absolute magnitudes is a class called Cepheid variables. They pulsate regularly in brightness with period lengths related to their size and absolute magnitudes. They are luminous stars that can be seen across the galaxy and in nearby galaxies. Via Cepheids, astronomers have determined distances to galaxies out to 100 million light years - the resolution limit for galactic Cepheids by current telescopes.

Cepheid Variable Stars.