Very Long Baseline Array

The Very Long Baseline Array (VLBA) is a system of ten <a href="/facts/Radio_telescope/SxIXUowL">radio telescopes</a> which are operated remotely from their <a href="/facts/Array_Operations_Center/udrTtKdL">Array Operations Center</a> located in <a href="/facts/Socorro%2c_New_Mexico/aVYuLNSr">Socorro, New Mexico</a>, as a part of the <a href="/facts/National_Radio_Astronomy_Observatory/1bIpL74E">National Radio Astronomy Observatory</a> (NRAO). These ten <a href="/facts/Radio_antenna/pGlcXBvc">radio antennas</a> work together as an array that forms the longest system in the world that uses <a href="/facts/Very_long_baseline_interferometry/2XDaPPMw">very long baseline interferometry</a>. The longest baseline available in this <a href="/facts/Interferometer/X3E1SsQT">interferometer</a> is about 8,611 kilometers (5,351 mi).
The construction of the VLBA began in February 1986 and it was completed in May 1993. The first <a href="/facts/Astrometry/9ycEEAvD">astrometrical</a> observation using all ten antennas was carried out on May 29, 1993. The total cost of building the VLBA was about $85 million. The array is funded by the <a href="/facts/National_Science_Foundation/FlDT8TbW">National Science Foundation</a>, and costs about $10 million a year to operate.
Each receiver in the VLBA consists of a <a href="/facts/Dish_antenna/8EpLcN6q">parabolic dish antenna</a> 25 <a href="/facts/Meter/hPhzc1CV">meters</a> (82 feet) in diameter, along with its adjacent control building. This contains the supporting <a href="/facts/Electronics/E4JhgISq">electronics</a> and machinery for the receiver, including low-noise electronics, <a href="/facts/Digital_computer/SQe1aK05">digital computers</a>, data storage units, and the antenna-pointing machinery. Each of the antennas is about as tall as a ten-story building when the antenna is pointed straight up, and each antenna weighs about 218 <a href="/facts/Metric_ton/gMymLmWv">metric tons</a> (240 <a href="/facts/Short_ton/b2fcrxHq">short tons</a>).

The signals from each antenna are recorded on a bank of approximately one-<a href="/facts/Terabyte/BNHUp9Qq">terabyte</a> hard disc drives, and the information is time-stamped using <a href="/facts/Atomic_clock/MF8nsXDR">atomic clocks</a>. Once the disc drives are loaded with information, they are carried to the Pete V. Domenici Science Operations Center at the NRAO in Socorro. There, the information undergoes <a href="/facts/Signal_processing/Npaja6zb">signal processing</a> in a powerful set of digital computers that carry out the interferometry. These computers also make corrections for the rotation of the Earth, the slight shifts in the <a href="/facts/Crust_(geology)/FYG1kP4F">crust of the Earth</a> over time, and other small <a href="/facts/Measurement_error/q7pa7bRt">measurement errors</a>.

Very Long Baseline Array open-in-new

Very Long Baseline Array