"Dark" Energy and Matter May Be Key to Understanding the Universe

One of the more pleasant things about being a science writer is that I never run out of subject material simply because scientific progress is constantly “rewriting the textbooks.” This is particularly true in the branch of astronomy known as cosmology.

Cosmology is the field that is concerned with the study of the universe on a large scale in order to understand how the universe came into existence, why it exists as it does today, and how (or if) it will end at some time in the future. As in any scientific research activity, cosmology relies on accurate observations and the accumulation of data, analysis of that data, and the formulation of theories and/or hypotheses that can be tested by further observations.

The currently accepted theory regarding the origin and current state of the Universe is known as the “Big Bang.” This theory proposes that the universe came into existence 13.7 billion years ago (± 200 million years) based on data obtained by NASA’s Wilkinson Microwave Anisotropy Probe (WMAP), which measured the microwave “background” radiation of the universe. Since the frequency (number of complete wave cycles occurring in 1 second) of this microwave background radiation is a function of its temperature, the age of the universe can be calculated by comparing the initial temperature (estimated) of the universe to the temperature data obtained by WMAP.

The first study involved an analysis of a series of images taken by the Hubble Space Telescope (HST) known as the Hubble Ultra Deep Field Survey. This study used a series of sophisticated light filters to selectively search for evidence of galaxy formation in the first 500 – 750 million years following the Big Bang.