Telescopes Have Grown from Huge to Humongous [Slide Show]
The next-generation, gigantic land-based telescopes are under construction, and they utterly dwarf their predecessors
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Telescopes Have Grown from Huge to Humongous [Slide Show]
- THE FIRST WAVE The Mount Wilson Observatory in California hosts two of the earliest significant, large ground-based telescopes. From 1917 to 1948 the 2.54-meter Hooker Telescope, funded by the Carnegie Institution of Washington, was the largest ground-based telescope in the world... Credits: Palomar/Caltech
- BIG BUT BUMBLING The BTA-6 is huge indeed, but it shows that bigger isn't always better. It was built by the Special Astrophysical Observatory of the Russian Academy of Sciences and was the first to utilize the now-standard two-axis altazimuth mount that lets the telescope move along both horizontal and vertical axes... Tyavin Paul/Wikimedia Commons
- TWIN TELESCOPES The twin 6.5-meter Magellan Telescopes at the Las Campanas Observatory in Chile saw first light in 2000 and 2002. They were built by the Carnegie Institution for Science, with help from Harvard University, Massachusetts Institute of Technology, the University of Arizona and the University of Michigan...
- PRODUCTIVE POWERHOUSE The four 8.2-meter telescopes that make up the Very Large Telescope are second only to the Hubble Space Telescope in productivity. Located in Chile and operated by the European Southern Observatory, the first of the four telescopes saw first light in 1998... Credit: ESO/S. Brunier
- SUM OF ITS PARTS Although Keck 1 saw first light in 1990, it wasn't until 1993 that it truly began its scientific observations. It was joined by its twin, Keck 2, in 1996. Both were constructed on Mauna Kea in Hawaii, the planned site for the future Thirty Meter Telescope proposed by the same group...
- CURRENT GIANT With a 10.4-meter segmented primary mirror, the Gran Telescopio Canarias in the Spanish Canary Islands is currently the largest single-aperture optical telescope in the world. It took seven years to build, and saw first light in 2007, although science operations did not truly begin until 2009... Credit: Pachango/Wikimedia Commons
- STARTING THE NEXT ERA The Magellan Telescopes at the Las Campanas Observatory in Chile will get a massive sibling in the early 2020s. The Giant Magellan Telescope will be made of up seven large mirrors, which will work together to form one massive mirror that is effectively 24.5 meters--about four times the size of the existing Magellans... Credit: Giant Magellan Telescope--GMTO Corporation
- WITHIN REASON In the mountains of northern Chile the European Southern Observatory is building the aptly named 39.3-meter Extremely Large Telescope, which should see its first light in 2024. At almost four times the size of the largest existing telescope, it will be able to probe exoplanetary atmospheres, perhaps even investigating a handful of potentially habitable worlds around nearby stars... Credit: ESO/L. Calçada
