Understanding Dark Energy with OzDES

In 1998 two groups of astronomers made the astounding discovery that the expansion of our Universe isn't slowing down as expect, but instead is speeding up! Our best explanation for this phenomenon is that the Universe's expansion is being "pushed" by some mysterious substance which we commonly refer to as Dark Energy.

Nobel Laureate and OzDES team member Professor Brian Schmidt explains the accelerating Universe. (Credit: ANU Media)

OzDES used the iconic 4-metre Anglo-Austrlian Telescope (AAT) at the Siding Spring Observatory in northern New South Wales, Australia. As the largest optical telescope in Australia, the AAT has been instrumental in numerous ground-breaking surveys. This has been especially true since the arrival of the "Two-Degree Field" (2dF) fibre positioning system for the AAOmega Spectrograph. This marvelous machine (seen in action in the video below) can place over 400 optical fibres over a 2-degree field of view on the sky, enabling astronomers to take a spectrum of numerous objects at once.

A night of 2dF in action on the Anglo-Australian Telescope. (Credit: Angel R. Lopez-Sanchez (AAO/MQ)