Very Large Array (VLA)

The Very Large Array, one of the world's premier astronomical radio observatories, consists of 27 radio antennas in a Y-shaped configuration on the Plains of San Agustin fifty miles west of Socorro, New Mexico. Each antenna is 25 meters (82 feet) in diameter. The data from the antennas is combined electronically to give the resolution of an antenna 36km (22 miles) across, with the sensitivity of a dish 130 meters (422 feet) in diameter.

How Does it Work?
The VLA is an interferometer; this means that it operates by multiplying the data from each pair of telescopes together to form interference patterns. The structure of those interference patterns, and how they change with time as the earth rotates, reflect the structure of radio sources on the sky: we can take these patterns and use a mathematical technique called the Fourier transform to make maps.

Who Uses It?
The VLA is used primarily by astronomers from around the world. It's also occasionally used for atmospheric/weather studies, satellite tracking, and other miscellaneous science.

The VLA is a multi-purpose instrument designed to allow investigations of many astronomical topics. Objects that are commonly studied include radio galaxies, quasars, pulsars, supernova remnants, gamma ray bursts, radio-emitting stars, the sun and planets, astrophysical masers, black holes, and the hydrogen gas that comprises a large portion of the Milky Way galaxy as well as external galaxies. In 1989 the VLA was used to receive radio communications from the Voyager 2 spacecraft as it flew by Neptune.

VLA Visitor Center
The VLA is open every day from 8:30 AM to sunset for free, self guided tours of the VLA and the VLA Visitor Center.

The VLA Gift Shop is open mid-May to mid-August 9:00 AM to 6:00 PM and mid-August to mid-May 9:00 AM to 4:00 PM. The Gift Shop is closed Thanksgiving, Christmas Eve, Christmas Day, and New Years Day.

Twice per year we offer guided tours to the public: the first Saturdays in April & October. These date coincide with the opening of the Trinity Site. During the summer, NRAO summer students provide tours on weekend. The tours are free and no reservations are needed.

Field Trips & Group Tours
For educational groups, we provide tour guides by staff members who volunteer for this duty. We need at least two weeks' notice to arrange a guided tour. If you're thinking about arranging an educational tour, look at our information on bringing your class to the VLA. Then give our Education and Public Outreach office a call at (575) 835-7243 to schedule the tour.

Very Large Array (VLA)
National Radio Astronomy Observatory
P.O. Box O
Socorro, NM 87801
Phone (505) 835-7000
www.nrao.edu