NRAO VLA, Courtesy of Juan Carlos, Magical Universe

NRAO/Karl V Jansky VLA, on the Plains of San Agustin fifty miles west of Socorro, NM, USA

The very large array or Karl V Jansky VLA is an observatory located on the plains of st. Augustine, between the towns of Magdalena and Datil, about 80 km west of Socorro, New Mexico, United States. The VLA is located at an altitude of 6970 ft [2.124] meters above sea level. It is part of the National Radio Observatory Observatory (NSF/NRAO), operated under cooperative agreement by Associated Universities, Inc. The Observatory consists of 27 independent antennas, each of which has a disc diameter of 25 metres and a weight of 209 tonnes. The antennae are aligned along three arms in the form of a Y-shaped array, and each arm is 21 miles. Using the railway tracks that follow each of these arms and a specially designed locomotive, the antennae can be physically relocated to a number of prepared positions, allowing with a maximum base of 36 km. Essentially the alignment acts as the only radio telescope with that diameter. The Highest Angular resolution that can be reached is about 0.05 seconds of arc.

There are four commonly used settings, called a (the major) to d (the minor), the minor configuration is when all the disks are less than 600 m from the central point. The Observatory normally passes through all possible configurations (including some hybrids) every 16 months, in other words, once the incredible effort needed to move two dozen highly sensitive scientific instruments of 209 tons has been carried out, Antennas are not moved again for a period of about three to four months. The also serves as a control centre for the Very Long Baseline Array (VLBA).