Editing Very Large Array (section)

== Characteristics ==
The [[radio telescope]] comprises 27 independent antennas in use at a given time plus one spare, each of which has a dish diameter of 25&nbsp;meters (82&nbsp;feet) and weighs {{convert|209|MT|ST|lk=on}}.<ref>{{cite web |url=http://www.vla.nrao.edu/ |title=Welcome to the Very Large Array! |work=vla.nrao.edu |publisher=National Radio Astronomy Observatory |access-date=2015-03-24}}</ref> The antennas are distributed along the three arms of a track, shaped in a wye (or Y) -configuration, (each of which measures {{convert|21|km}} long). Using the rail tracks that follow each of these arms—and that, at one point, intersect with [[U.S. Route 60 in New Mexico|U.S. Route 60]] at a level crossing—and a specially designed lifting locomotive ("Hein's Trein"),<ref>{{cite news |first=Joe |last=Holley |url=https://www.washingtonpost.com/wp-dyn/content/article/2008/05/28/AR2008052803211.html |title=Hein Hvatum, 85; Engineered Telescope to the Heavens |newspaper=[[The Washington Post]] |date=May 29, 2008 |access-date=2015-03-24}}</ref> the antennas can be physically relocated to a number of prepared positions, allowing [[aperture synthesis]] [[interferometry]] with up to 351 independent baselines: in essence, the array acts as a single antenna with a variable diameter. The [[angular resolution]] that can be reached is between 0.2 and 0.04 [[arcseconds]].<ref name="specs">{{Cite web |title=Very Large Array |url=https://public.nrao.edu/telescopes/vla/vla-basics |website=National Radio Astronomy Observatory |publisher=The National Radio Astronomy Observatory}}</ref>

There are four commonly used configurations, designated A (the largest) through D (the tightest, when all the dishes are within {{convert|600|m}} of the center point). The observatory normally cycles through all the various possible configurations (including several hybrids) every 16 months; the antennas are moved every three to four months. Moves to smaller configurations are done in two stages, first shortening the east and west arms and later shortening the north arm. This allows for a short period of improved imaging of extremely northerly or southerly sources.<ref>{{Cite web |title=VLA Configurations |url=https://public.nrao.edu/vla-configurations/ |access-date=2023-08-08 |website=National Radio Astronomy Observatory |language=en-US}}</ref><ref>{{Cite web |title=Configuration Plans and Proposal Deadlines — Science Website |url=https://science.nrao.edu/facilities/vla/proposing/configpropdeadlines |access-date=2023-08-08 |website=science.nrao.edu}}</ref>

The frequency coverage is {{frequency|74|MHz}} to {{frequency|50|GHz}} (400&nbsp;cm to 0.7&nbsp;cm).<ref name="overview">{{cite web |url=http://www.vla.nrao.edu/genpub/overview/ |title=An Overview of the Very Large Array |work=vla.nrao.edu |publisher=National Radio Astronomy Observatory |access-date=2015-03-24}}</ref>

The Pete V. Domenici Science [[Array Operations Center|Operations Center]] (DSOC) for the VLA is located on the campus of the [[New Mexico Institute of Mining and Technology]] in [[Socorro, New Mexico]]. The DSOC also serves as the control center for the [[Very Long Baseline Array]] (VLBA), a [[Very Long Baseline Interferometry|VLBI]] array of ten 25-meter dishes located from [[Hawaii]] in the west to the [[U.S. Virgin Islands]] in the east that constitutes the world's largest dedicated, full-time astronomical instrument.<ref>{{cite web |url=https://science.nrao.edu/facilities/vlba |title=Very Long Baseline Array |work=science.nrao.edu |publisher=National Radio Astronomy Observatory |access-date=2015-03-24}}</ref>