The "ELT" stands for Extremely Large Telescope, which refers to a new generation of ground-based telescopes with significantly larger apertures and advanced technologies compared to existing telescopes. While there are multiple projects and initiatives in progress, the primary ELT that is currently under construction is the Extremely Large Telescope (ELT) by the European Southern Observatory (ESO). Here are some other notable telescopes in the ELT era:
Giant Magellan Telescope (GMT): The GMT is being built in Chile by an international consortium of universities and research institutions. With its seven primary mirrors, each 8.4 meters in diameter, the GMT will have a total effective aperture of 24.5 meters.
Thirty Meter Telescope (TMT): The TMT is a joint project between the United States, Canada, Japan, China, and India. It will feature a primary mirror with a diameter of 30 meters, making it one of the largest telescopes in the ELT era.
Magellan Telescopes: Although not classified as ELTs, the twin Magellan Telescopes, located in Chile, also contribute to the era of extremely large telescopes. Each telescope has a primary mirror of 6.5 meters in diameter and utilizes advanced adaptive optics technology.
James Webb Space Telescope (JWST): Although not a ground-based telescope, the JWST is worth mentioning as it represents a significant advancement in space-based astronomy. With a primary mirror diameter of 6.5 meters, it is larger than the Hubble Space Telescope and will be positioned in space, beyond the Moon's orbit.
These telescopes, including the ELT, GMT, TMT, and JWST, will significantly enhance our ability to observe the universe and provide unprecedented insights into various astronomical phenomena.