Unlocking the secrets of the universe with the world’s largest optical telescope!

  • The Extremely Large Telescope (ELT) will be the world’s largest optical telescope with a 128-foot primary mirror.
  • Constructed by the European Southern Observatory in Chile, the ELT aims to detect and image rocky exoplanets.
  • The telescope’s location atop Cerro Armazones offers excellent atmospheric conditions for astronomical observations.
  • The ELT’s mirror consists of 798 hexagonal segments, polished to an accuracy of 10 nanometers.
  • Adaptive optics technology will enhance the telescope’s resolution, allowing it to counteract atmospheric turbulence.
  • The ELT will focus on eight main science areas, including exoplanets, black holes, and cosmology.
  • Construction is ongoing, with the first light expected by 2028.

The Extremely Large Telescope (ELT) is set to become the largest optical telescope in the world, boasting a primary mirror that measures an impressive 128 feet (39 meters) in diameter. This monumental project, undertaken by the European Southern Observatory (ESO) in Chile, comes with a hefty price tag of 1.3 billion euros (approximately $1.4 billion). The ELT is designed to detect and potentially image rocky exoplanets located in the habitable zones of other stars, marking a significant advancement in our quest to understand the universe. nnConstruction is taking place on Cerro Armazones, a mountaintop in Chile’s Atacama Desert, chosen for its exceptional atmospheric and climatic conditions. The site is about 12 miles (20 kilometers) from the ESO’s existing Very Large Telescope on Cerro Paranal. To prepare for the ELT, the summit of Cerro Armazones was leveled in 2014, reducing its height by 60 feet (18 meters). The dry climate, with only 4 inches (10 centimeters) of annual rainfall, and minimal light pollution from distant towns make it an ideal location for astronomical observations. nnThe ELT’s primary mirror is not a single piece of glass but is composed of 798 hexagonal segments, each measuring 5 feet (1.5 meters) across and 2 inches (5 centimeters) thick. An additional 133 segments are included for maintenance, bringing the total to 949 segments, all completed by June 2024. These segments were polished to an extraordinary precision of 10 nanometers, ensuring the highest quality of observation. nnTo combat the effects of Earth’s turbulent atmosphere, which can distort starlight, the ELT employs advanced adaptive optics technology. This system uses lasers to create artificial guide stars, allowing the telescope to adjust its mirrors in real-time to counteract atmospheric disturbances. The ELT features a dual adaptive-optics system, including the largest adaptive mirror ever constructed, equipped with over 5,000 actuators that can adjust thousands of times per second. nnThe ELT will focus on eight key scientific areas: the solar system, exoplanets, stars, black holes, galaxies, cosmology and dark matter, fundamental physics, and unexpected discoveries. It will study the atmospheres of gas giants, probe rocky exoplanets for biosignatures, and investigate the formation of stars and galaxies. The telescope is expected to gather 15 times more light than the current largest optical telescope, the Gran Telescopio Canarias, and provide views 15 times sharper than the Hubble Space Telescope. nnAs of July 2024, the construction of the ELT is progressing, with the last mirror segment delivered for polishing. The installation of the mirror segments is scheduled for 2027, with the first light anticipated by 2028. Following a period of testing and calibration, the ELT aims to begin its scientific operations by the end of the decade, promising to unveil new insights into the cosmos.·

Factuality Level: 9
Factuality Justification: The article provides a comprehensive overview of the Extremely Large Telescope (ELT), including its specifications, construction details, and scientific goals. It is well-researched, contains factual information, and avoids sensationalism or bias. However, it could be slightly more concise, as some sections contain detailed technical descriptions that may not be essential for all readers.·
Noise Level: 9
Noise Justification: The article provides a detailed and informative overview of the Extremely Large Telescope (ELT), including its construction, technology, and scientific goals. It supports its claims with evidence and data, maintains focus on the topic, and offers insights into the telescope’s potential contributions to astronomy. The scientific rigor and intellectual honesty are evident throughout, making it a valuable resource for readers interested in this subject.·
Public Companies: European Southern Observatory ()
Private Companies: Schott,Safran Reosc
Key People:

Financial Relevance: Yes
Financial Markets Impacted: The construction of the Extremely Large Telescope (ELT) involves significant financial investment, impacting companies involved in optics and construction, as well as potential future scientific funding and collaborations.
Financial Rating Justification: The article discusses the financial aspects of building the ELT, including its cost and the companies involved in its construction and optics, which are relevant to financial markets and investments.·
Presence Of Extreme Event: No
Nature Of Extreme Event: No
Impact Rating Of The Extreme Event: No
Extreme Rating Justification: The article discusses the construction and features of the Extremely Large Telescope (ELT) but does not mention any extreme events such as natural disasters, crises, or accidents.·

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