The incredible £775m telescope that's biggest in world and nearly same size as Big Ben

ELT is the biggest of its kind (Image: Getty)

This out-of-this-world telescope is the biggest of its kind. It is made up of five mirrors that can gather 100 million times the light a human eye can and is contained by a steel dome, which weighs 6000 tonnes.

The Extremely Large Telescope (ELT) is a £775million telescope built in Chile’s Atacama Desert – one of the driest places on Earth. 

The telescope built by 16 nations in the European Southern Observatory (ETO) will produce images of planets that are 15 times sharper than NASA’s Hubble Space Telescope.

ELT's images will be sharper than NASA's Hubble Space Telescope (Image: Getty)

In a video produced by the constructions video channel, The B1M, Roberto Tamai, programme manager, said: “The telescope will open the window towards parts of our universe that today we don’t even imagine.”

The location of the construction site was selected over 14 years ago, taking in many factors such as the content of wind, rain, ground conditions and light pollution. 

However, it wasn’t until 2019 that the foundations and outline of the structure took place, and then a further four years later, when construction of the actual telescope began.

The Extremely Large Telescope is protected by a dome that's 80m high, only 16 metres shorter than Big Ben.

The ELT is being built in one of the driest places on earth (Image: Getty)

The original construction plan proposed a telescope with a 100-meter diameter mirror, initially named the Overwhelmingly Large Telescope.

However, the team realised that the design would be too complex. As a result, they went for a telescope with a 33-meter diameter primary mirror and a 4.2-meter diameter secondary mirror, which they named instead the Extremely Large Telescope.

It is expected to be completed and begin operations in 2028, which will make it the world’s largest optical telescope.