High-Z Supernova Search
Table of ContentsThe Expanding Universe [1] [2] [3]
The Fate of the Universe
Supernovae
Type Ia Supernovae
Searching for Distant Type Ia Supernovae
Search Results
Search Conclusions
The Expanding Universe
Doppler shift is heard when sound increases or decreases in pitch as sound sources move towards or away from us. The pitch is lowered. as objects move away and is raised as the come towards us. Light is Doppler shifted in a similar way - towards red as light sources move away, and towards blue as objects travel towards us.I am indebted to the Slipher family for helping fund my undergraduate education through the University of Arizona's Slipher scholarship. In 1916 Vesto Slipher observed about 50 nearby spiral nebulae by spreading their light out using a prism, and recording the results onto film. The results confounded him and astronomers of the day. The light from most of the objects he observed was stretched to redder colours, Most of the spiral nebulae in the Universe are moving away from us.
The lower spectrum shows a galaxy as Slipher would have seen it. The dark lines, where elements such as Sodium absorb light, are stretched towards red.