The construction for the European Southern Observatory's (ESO) Extremely Large Telescope (ELT) began on Friday, May 26, and they marked the event with a momentous ceremony. With the construction of the soon to be largest optical/infrared telescope in the world underway, what are some of the things that the ELT could discover?

Construction Begins For The World's Largest Optical Telescope

Though construction of the road and platform for the telescope began in 2014, Friday's ceremony marked the historic moment for the ESO as the beginning of the actual construction of the ELT.

The ELT, a 39-meter (128 feet) telescope that can provide images with a resolution 15 times sharper than the Hubble Space Telescope, will be constructed at the top of Cerro Armazones, a 10,000 feet peak in Chile. It will be kept by a rotating dome that is 85-meters (279 feet) in diameter — a size that is similar to that of a football pitch.

"With the symbolic start of this construction work, we are building more than a telescope here: it is one of the greatest expressions of scientific and technological capabilities and of the extraordinary potential of international cooperation," said Chilean President Michelle Bachelet Jeria in her speech.

'The World's Biggest Eye On The Sky'

According to the ESO, the purpose of building the ELT is to "tackle the biggest scientific challenges of our time." These challenges include many that current space and science missions are tackling today, such as searching for Earth-like planets in habitable zones where life could possibly exist.

With a main mirror of 39-meter (128 feet) in diameter, four times larger than the current largest optical telescopes, the ELT can collect more light, and gather higher levels of detail.

With its exceptional specifications and capability to observe more distant objects, the ELT will be able to give clues for us to understand how the first objects in the universe were formed such as the primordial stars, primordial galaxies, and black holes. Apart from their formation and relationships with each other, ELT may also give insight as to how the first galaxies have evolved through time, as well as how they are still currently evolving.

What's more, the ELT will be useful in understanding star formation history in observable galaxies, and in observing exoplanets and their atmospheres.

Perhaps the more exciting and ambitious goal for the ELT is one that may change the way we understand and look at physics. As an exceptional tool in space observation, one of ELT's main goals is to observe and make a direct measurement of the universe's expansion.

With the ELT equipped to tackle and complete many ambitious scientific goals, it truly is set to become "the world's biggest eye on the sky."