Huge telescopes dot mountainsides around the world.

From Hawaii to Chile, scientists seek out the perfect site with fair weather and dark, clear skies to peer deeply into space, clocking the movements of distant stars, planets, and other objects far beyond what we can see with the naked eye.

 

A new observatory called the Giant Magellan Telescope, currently being built in Chile, should eventually be able to see far-off alien worlds and even take a look at their atmospheres.

But right now, the project is in a critical phase.

Scientists are in the process of casting the seven huge mirrors that will be used to allow the telescope to do its astronomical work.

The team is now casting the fifth mirror, a process that requires melting tons of glass in a furnace that spins five times per minute, according to the Giant Magellan Telescope Organization (GMTO).

After cooling, the mirror will be polished down into an exact shape that will hopefully help make the telescope take even sharper images than large space-based observatories like the Hubble Telescope.

Once these mirrors are ready and the observatory site is completed, scientists will open another eye on the universe.

But it hasn’t always been smooth sailing for this new project. Crafting these mirrors isn’t easy, though the reasons why are a bit technical.

“In making the first mirror we found that some basic old-world technical issues, such as hydroplaning, material creep and similar apparently simple issues that had been resolved for symmetric, on-axis, mirrors suddenly reared up as roadblocks to achieving the desired optical tolerances for the off-axis mirrors,” Patrick McCarthy, GMTO Vice President, said via email.

“These have been resolved, but we realize that other unexpected challenges will arise in the future.”

It took the GMTO a long time to get to this point, and it still has a ways to go before the telescope is operational. The observatory has been in the works for 14 years so far, and the telescope likely won’t be fully operational until 2025 or 2026.

Scientists first started putting the project together in 2003, with a design review occurring during the span of three years. Construction began in 2015, and “first light” — the moment when the telescope will start its preliminary test run — is expected in 2023.

While it may seem somewhat slow, this timeframe is about average, or even quick, for most large science projects of this kind.

“Megaprojects in science, as in other areas of society, often take 20 years from inception to completion,” McCarthy added.

“LIGO (Laser Interferometer Gravitational Observatory) is a good example, as is the Large Hadron Collider at CERN. The Hubble Space Telescope and the James Webb Space Telescope have been very long-term projects — but they have all been, or promise to be, great successes,” he said.