The Giant Magellan Telescope requires seven huge mirrors, each one costs over 20 million USD.

Huge telescopes require huge mirrors - a task that can’t be done with shortcuts. Telescope mirrors are so challenging because they are not only massive, but they need incredible amounts of precision.

This featured video of IEEE Spectrum shows part of the process of creating the mirror for the Giant Magellan Telescope (GMT). The gigantic mirrors posed a considerable engineering challenge to all involved.

The GMT is a long-term project that will see it eventually become the largest telescope in the world.

The Giant Magellan Telescope Organization (GMTO) and a team at the University of Arizona's Richard F. Caris Mirror Laboratory cast the first of the telescopes seven mirrors back in 2005.

The other mirrors and final construction of the building to house the technology is expected to be complete in 2025. It will consist of seven 8.4-meter-wide mirrors will combine to serve as a 24.5-meter mirror.

The GMT will have 10 times the resolution of the Hubble Space Telescope.

It will help astronomers examine the stars in a way that has never before been possible. Each of the seven mirrors costs the US 20 million dollars to make and takes more than two years to build.

Every stage requires the input of many engineer and careful planning to ensure there are no flaws or mistakes. Every mirror requires over 17,000 kilograms of special glass, all of which needs a thorough inspection to ensure absolute premium quality.

Watch the full video to start to understand the amazing complexity and detail involved in the creation of each mirrors of GMT.