A five year program to map the universe in its most detailed survey ever got underway in Arizona, US with 5,000 mini telescopes aiming to decode Dark Energy — the force that is not just driving the universe’s expansion but also accelerating it. Each one of these mini telescopes will be able to spot a galaxy every 20 minutes — which means that in one year, this super telescope would have surveyed more galaxies in the universe than all other telescopes combined.
How does it work: Researchers from around the globe, who are taking part in this study, have attached an optical device for measuring the spectrum of light from any source, calling it the Dark Energy Spectroscopic Instrument (DESI), to the 4m Mayall telescope at the Kitt Peak observatory in Arizona. Inside the DESI are 5,000 optical fibres each of which will act as an independent telescope and together, they will be able to scan 360,000 galaxies in a single day. Using previous surveys to draw a map of the Universe, this super telescope will be studying 35 million galaxies to understand Dark Energy. Given that this super telescope can see objects 10 billion light years away, it means that it can tell us about cosmic events that occurred 10 billion years back.
What’s Dark Energy: It was the name coined to describe the force that is accelerating the Universe’s expansion — after scientists discovered in 1998 that contrary to the expectations propounded by the Big Bang Theory that the Universe’s expansion would not only slow down but that it will also begin to contract as a result of gravitational pull, not only was the Universe expanding, but its expansion was speeding up. Dark Energy is said to make up 68% of the Universe while Dark Matter makes up 27% and the remaining matter — which includes everything on Earth and everything observed through various instruments — constitutes just 5% of the Universe.