Astronomers have released a stunning infrared view of the deep Universe containing a number of galaxies created in the first billion years following the birth of the cosmos. The image is the result of over 1,000 hours of exposure time from the 3.8-m (12.4-ft) United Kingdom Infrared Telescope (UKIRT) located near the summit of Mauna Kea in Hawaii.
The recently released images form part of the Ultra-Deep Survey (UDS), which is the most far-reaching of five separate endeavours that form the UKIRT Infrared Deep Sky Survey (UKIDSS). The UDS imaging campaign focused on an area the equivalent of four times the full moon in the night sky. The impressive infrared capabilities of the UKIRT telescope were vital to the success of the campaign in order to combat a phenomenon known as "redshift."
Redshift occurs when light from distant stars is stretched into longer wavelengths as it travels the vast cosmic distance from its source to our telescopes. Infrared telescopes are best suited to capturing this ancient light.
Zoomed in view of a small section of the UDS field, containing ancient galaxies imaged as they were 9 billion years ago when the light left its source
UDS contains around 250,000 ancient galaxies that were created relatively soon after the cataclysmic birth of the Universe via the Big Bang. As with all astronomy images, we are never viewing the subject of our observations in real time. Light is known to travel at 299,792,458 meters per second through a vacuum, and while this may sound stupendously fast, it still takes billions of years to travel the vast gulf that separates the galaxies.
On average, light emitted by the galaxies captured in the UDS survey left its source 9 billion years ago, so we are essentially looking at the structures as they were at that time. Analyzing such a large sample of ancient galaxies could allow astronomers to fill in a number of blanks regarding the formation and evolution of the vast cosmic structures.
For example, the data could explain why the most massive galaxies are elliptical in shape, while medium sized galaxies, such as our own Milky Way, often take a disk-like form with pronounced spiral arms, and even shed light on one of the Universe's most enigmatic phenomenon, dark matter.
Source: University of Nottingham