11. Very Large Array

Very Large array (VLA) is situated in New Maxico, USA and is operated by NRAO (National Radio Astronomy Observatory).

The red dot is showing position of VLA on earth

Very Large Array is a collection of 27 radio telescopes, each 25m in diameter. They are distributed in a Y-configuration and each of these telescopes can be moved along the railroad tracks. In 2012 it was renamed as Karl G. Janskey Very Large Array after Karl Guthe Jansky who built his own 14.6m rotatable antenna and later in 1931 discovered radio waves coming from the center of our galaxy.

Very Large Array 
APOD May 14, 2006
Credit: Dave Finley, AUI, NRAO, NSF

VLA had been used for SETI (Search for Extraterrestrial Intelligence).
We know that our galaxy - Milky Way is the second largest in the Local Group, the first and third are M31 (Andromeda galaxy) and M33 (Triangulum galaxy) respectively. So astronomers pointed the VLA telescopes to look for radio signals of 21cm from these two galaxies but they didn't find any.

VLA radio telescopes also discovered the first Einstein Ring gravitational lens. In gravitational lensing, when a heavy object comes in front of a star, galaxy or quasar it bends the light coming from them and thus distorts is totally. Sometimes it forms a ring and sometimes multiple images. And the first Einstein Ring was made because the image of a quasar was bent by a galaxy in between.