CNC Wonders: Giant Magellan Telescope

It’s pretty amazing what can be accomplished using the power, repeatability and precision of modern CNC equipment – take for instance the Giant Magellan Telescope being built right now to be released in 2020.

Very much an awesome demonstration of manufacturing engineering capability! There is now way the design of the telescope would be possible without the wonders of CAD, let alone built by anything but a CNC machine.

Technically, the Giant Magellan Telescope itself is a CNC machine, possible only because it was built digitally and manufactured using CNC machines and highly skilled operators.

All this precision and cutting edge technology isn’t cheap, 700 million dollars to produce a LAND BASED telescope that produces a resolving power that’s ten times better than the next best visual telescope ever made, the Hubble Space Telescope. Although Hubble cost 2.5 billion dollars (initially projected to cost 400 million), the Giant Magellan Telescope is able – if it stays on budget – of producing 10x the resolution at a third the relative production costs. This is the power of CNC!

Giant Magellan Telescope

The Giant Magellan Telescope is made-up of adaptive optics that use larger mirrors (each 90ft or 24.5m in diameter) to focus light traveling billions of light years onto a very small point at the end of the telescope. The adaptive optics (and I’m sure custom software) are needed to correct for the atmospheric distortions that come from Earth, something the Hubble Space Telescope didn’t have to contend with (hence why it was in orbit).

How precise does the Giant Magellan Telescope need to be? The cast mirrors have to be polished – over the course of an entire year – to within 25 nanometers or a thousand times thinner than a human hair. Any mirror distortions means the images will be blurry, similar to what happened to Hubble Space Telescope the first time around BUT at least this one is ground based, which means a longer shelf life and easier fixes.

Giant Magellan Telescope

The entire 30 meter Giant Magellan Telescope will be built atop Mauna Kea in Hawai to begin observing the Universe in 2025 but the largest telescope ever to be in production – the European Extremely Large Telescope – will be built in Chile, will have a main mirror that’s 138 ft (42 meters).