 The EDGE experiment is a balloon experiment that will study variations in the cosmic infrared background over the sky to further our understanding of large-scale structures in the Universe. A key goal of modern observational cosmology is to understand and trace the formation of large-scale structure throughout the history the Universe. We now know from studies of the Cosmic Microwave Background Radiation (CMBR) that the matter distribution in the Universe was extremely uniform when it was around 300,000 years old. As time progressed, gravitational collapse amplified the small deviations from uniformity into the rich structures that we see in the Universe today. In the nearby Universe, we have made great progress reaching back to a time when the Universe was perhaps half its current age, at approximately 6 billion years old. What happened in the time between 300,000 and 6 billion years? A key remaining observational milestone occurred when the Universe was only a few billion years old - when the first objects in the Universe were sufficiently compressed to ignite. This light was absorbed by dust in the local protogalaxy environment and then re-emitted in the infrared. The integrated light from all such dust in the line-of-sight is the Cosmic Infrared Background (CIB). Because the CIB is emitted by these first galaxies, it traces their distribution in space, thus providing a new observational handle on this crucial early era. EDGE will measure the 'clumpiness' of this light from the Universe over the sky, back to the time the first galaxies ignited. This will complement the measurements from the CMBR and from the modern era to form a more complete history of large-scale structure formation.
The EDGE scientific goals are an integral part of the NASA Office of Space Science strategic plan: "Understand the structure of the Universe, from its earliest beginnings to its ultimate fate," and the specific goal: "Determine the size, shape, age, and energy content of the Universe." EDGE also directly addresses two "key problems" in the McKee-Taylor Decadal Report of 2001 - "determine the large-scale properties of the Universe," and "study the dawn of the modern Universe."
Project Website
|
