The National Science Foundation’s Very Long Baseline Array (VLBA), a continent-wide radio telescope system, will once again officially be a part of the National Radio Astronomy Observatory (NRAO) and will undergo a technical upgrade to significantly improve its capabilities.
When a new cooperative agreement between the NSF and Associated Universities, Inc., (AUI) for managing the NRAO took effect in 2016, the VLBA exited NRAO and became part of an independent facility called the Long Baseline Observatory (LBO). AUI then managed the LBO under a separate cooperative agreement with NSF.
Now, a new cooperative support agreement for operating the VLBA returns the facility to the NRAO.
“The scientific community can be assured of the VLBA’s continuing availability for forefront research with this consolidation,” said NRAO Director Tony Beasley. “In addition, NSF is providing funding for a technical upgrade that will make the VLBA an even more valuable tool for research,” he added.
The VLBA was dedicated in 1993. Operated remotely from a control center at NRAO’s Domenici Science Operations Center in Socorro, NM, it includes 10, 240-ton dish antennas distributed across U.S. territory from the Pacific to the Caribbean. The antennas are located at Mauna Kea, Hawaii; Brewster, WA; Owens Valley, CA; Kitt Peak, AZ; Pie Town, NM; Los Alamos, NM; Fort Davis, TX; North Liberty, IA; Hancock, NH; and St. Croix, U.S. Virgin Islands.
Data from each VLBA antenna is recorded on high-capacity disk drives and shipped to Socorro, where it is combined electronically with the data from every other antenna to make the VLBA work as a single radio telescope with extremely great resolving power, or ability to see fine detail. The new upgrade, funded by a $2.5 million award from NSF, will improve communication between the antennas and the control center by adding fiber optic connections to the five antennas that currently lack such connections.
This improved connectivity will provide much better capability to diagnose problems in real time, support some time-critical observations, and allow upgrading operating systems and software using the higher data capacity of the fiber links. The work is expected to be completed in approximately a year.
“These capabilities will enhance our ability to effectively support the researchers who use the VLBA,” said Walter Brisken, former LBO Director.
The VLBA has made major contributions to many areas of astronomical research, ranging from studying galaxies as they were when the universe was a fraction of its current age to observing asteroids in our solar system. The VLBA’s sharp radio “vision” has allowed it to precisely measure distances in our Milky Way, significantly revising the map of our home galaxy.
The VLBA also has made the most accurate distance measurements ever for objects beyond the Milky Way. In addition, the VLBA is used to refine the reference system astronomers use to precisely define positions in the sky.
Recently, the VLBA made key observations that resolved an important question about the aftermath of a collision of two neutron stars — a phenomenon that was the first event in the universe that scientists were able to study using both gravitational waves and electromagnetic waves.
The VLBA also can be used to precisely determine the locations of its antennas, allowing geophysicists to measure the effects of continental drift and climate change.