The upcoming Extremely Large Telescope (ELT) is very aptly named. When it’s completed in 2024, it will be the largest optical telescope in the world, with a mirror more than 120 feet across.

The world's largest telescope is almost as big as your house—and it’s unlocking the universe’s biggest mysteries.

Oct. 4 -- Astronomers are never satisfied. It isn’t enough to study objects in the distant sky that are so faint they elude even the most powerful telescopes in the world. It just keeps their ...

The system can accommodate a mirror up to 0.9 meters in diameter, and there is no reason the design could not be scaled up to accommodate even larger mirrors or mirror segments, Phillips said. The ...

The GTC is based on the design of the Keck telescope in that itss main mirror is made up of 36 smaller segments. It's a US$179 million telescope that began operations in 2007, although it wasn't ...

The Keck Telescopes in Hawaii pushed the boundary by constructing a 10-meter mirror made of many smaller hexagonal mirrors arranged together. The Keck works because the only requirement for a ...

Primary mirror of the Keck I telescope. This shot, taken in infrared light using the adaptive optics system at Hawaii's Keck Observatory, shows Neptune and its moon Triton (lower right). A shot of ...

A similar hexagonal system has operated on the twin 10-metre Keck telescopes in Hawaii since the 1990s, and Feinberg acknowledges that his team learned a lot from Keck’s optical design. As at Keck, ...

The mirror at its heart is just 7.9 ft. (2.4 m) across, which gives it only about one-seventeenth of the light-gathering power of the 33-ft. (10 m) twin Keck telescopes, atop Hawaii’s Mauna Kea.

The Keck telescopes and the Milky Way. Image via Flickr ... This method works by deforming the telescope’s mirror in real time in order to overcome fluctuations in the atmosphere.