The Very Large Telescope (VLT) consist of four separate optical telescopes that each have 8.4 meter aperture. The VLT is a project of the European Southern Observatory organization.


''The four telescopes of the European Southern Observatory Paranal site. The VLTI (Very Large Telescope Interferometer) building is the low structure in front of the telescopes (with the black rectangle in the roof).


One of the four telescopes that make up the VLT, this one is named Kueyen. The 8.4 meter mirror can be seen (as an oval patch of lightness) below the large horizontal grey beam. Scale is given by the person at the bottom of the picture.

It is located at the Paranal Observatory on Cerro Paranal, a 2,635-m high mountain in the Atacama desert in northern Chile.

The VLT consists of a cluster four of large telescopes, and an interferometer (VLTI) which will be used to resolve fine features. The telescopes have been named after the names of some astronomical objects in the local Mapuche language: Antu (The Sun), Kueyen (The Moon), Melipal (The Southern Cross), and Yepun (Venus)

The VLT can be operated in three modes:

  • as a set of independent telescopes
  • as a single large incoherent instrument, for extra light-gathering capacity
  • as a single large coherent interferometric instrument, for extra resolution

In its full interferometric operating mode, the four telescopes provide the same light gathering ability as a single 16m telescope, making it the largest optical telescope in the world. The VLT is intended to achieve an effective angular resolution of 0.001 arcsecond at a wavelength of 1 µm. This is an angle of 0.000000005 radians, equivalent to resolving a target 2 meters across at the distance between the Earth and Moon.

This should easily resolve the 5-metre wide Lunar Module bases left on the Moon by the Apollo moon missions, and a group of European scientists intends to do just that to challenge Apollo moon landing hoax accusations.

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