The European Space Observatory’s Very Large Telescope (VLT) has achieved a new milestone thanks to its ESPRESSO tool. With this, all four of VLT’s 8.2-meter Unit Telescopes are working together as a single giant telescope. This is a huge achievement for the VLT, which was first thought of back in the 1980s, basically transforming it into the world’s largest optical telescope.
ESPRESSO is a spectrograph instrument that receives light from each of the four Unit Telescopes via a series of lenses, mirrors, and prisms. The ability exists to receive light from only one of the Unit Telescopes as well as all four, giving researchers a wider array of options. Previously the Unit Telescopes fed light to the VLT’s Interferometer, but that is limited when it comes to faint objects.
Feeding all four Unit Telescopes’ light to the spectrograph instrument has been called a game-changer for researchers who will get access to high-resolution spectrographs and the ability to investigate those aforementioned faint objects.
Researchers have big plans for the VLT’s ESPRESSO instrument, which will be used to find and characterize exoplanets, as well as look for “variability of the fundamental constants of physics.” That latter work will involve observing faint, faraway quasars, making the light-collecting power of all four Unit Telescopes fed into the instrument vital.
This is only the start, researchers tease, with ESO director general Xavier Barcons pointing out that this gives us “an enticing foretaste of what the next generation of telescopes, such as ESO’s Extremely Large Telescope, will offer in a few years.” Anyone can virtually explore VLT and view live webcam feeds from the observatory here.