Ventspils International Radio Astronomy Centre
Radio astronomy installation in Latvia
From Wikipedia, the free encyclopedia
Ventspils International Radio Astronomy Centre (Latvian: Ventspils Starptautiskais radioastronomijas centrs – VIRAC) is an engineering research institute of Ventspils University of Applied Sciences in Latvia. It operates a radio astronomy observatory at Irbene, in Ance parish, Ventspils Municipality.[1] The observatory has two fully steerable parabolic radio telescopes, RT-32 and RT-16, with dish diameters of 32 metres (105 ft) and 16 metres (52 ft), respectively.[2] It also hosts station LV614 of the Low-Frequency Array (LOFAR).[3]
The RT-32 radio telescope | |
| Alternative names | VIRAC |
|---|---|
| Location | Latvia |
| Coordinates | 57°33′13″N 21°51′18″E |
| Website | en |
| Telescopes | |
 | |
 Related media on Commons | |
History
The observatory occupies a former Soviet military site. The university dates the establishment of the Irbene antenna complex to 10 June 1967;[1] a 2015 LSM report dates the start of military operations to 1974.[4]
The Latvian Academy of Sciences founded VIRAC on 22 July 1994. In 1996, it was reorganised as a state-owned, non-profit scientific company. The centre became part of Ventspils University College, subsequently renamed Ventspils University of Applied Sciences, on 16 December 2004. On 1 March 2010, the university's Engineering Research Centre was incorporated into VIRAC.[1]
RT-32
RT-32 has a fully steerable 32-metre (105 ft) parabolic dish. Its receiving and recording equipment supports very-long-baseline interferometry (VLBI), in which observations are combined with those of other radio telescopes.[2][5]
In late 2014, the dish was removed from its tower and placed in a shelter for restoration. Work included repairs to the reflector panels and replacement of corroded parts, addressing damage from water and lightning. The wider renovation programme cost about €16 million, including approximately €1.5 million for the panels, with European Union, Latvian state and local-government funding.[4] The dish was lifted back onto the tower on 10 June 2015.[6]
The upgraded telescope completed successful VLBI tests with the European VLBI Network (EVN) in October 2015, at frequencies of 1.6, 5, 6.7 and 8 GHz.[2] Irbene became an EVN member station in October 2016.[5]
In July 2022, RT-32 received a larger receiver cabin to replace the original structure from the 1960s. The centre's director, Aleksejs Klokovs, explained that the additional space allowed more equipment to be installed and reduced the time needed to change instruments.[7]
RT-16
RT-16 is a 16-metre (52 ft) Cassegrain radio telescope. A 2017 evaluation described its cryogenically cooled receiver, covering frequencies from 4.5 to 8.8 GHz. Upgrades to its reflector, tracking equipment and receiving system were tested in observations that year, including EVN sessions and single-dish monitoring of active galactic nuclei and spectral lines.[8]
By November 2024, RT-16 had also been fitted with a transmitter. At that time, the centre was preparing to offer spacecraft communications services in addition to receiving radio signals.[9]
LOFAR
The LOFAR-LATVIA station opened at Irbene in October 2019, following antenna installation during the summer.[10] Designated LV614, it consists of 96 low-band crossed-dipole antennas and 96 high-band tiles, each containing 16 crossed Vivaldi antenna elements.[3] Unlike RT-32 and RT-16, it uses arrays of small antennas rather than a single steerable dish.[11][3] Optical-fibre connections link the station to the international LOFAR network, allowing its observations to be combined with those of stations elsewhere in Europe.[10]
Research
The centre's astronomical research includes solar activity and fast radio bursts.[9] Its researchers also observe astrophysical masers and model chemical processes in interstellar clouds and regions of star formation.[1]
A study published in 2023 described monitoring of 42 sources of 6.7-GHz methanol maser emission between March 2017 and October 2022. Both Irbene telescopes contributed, with RT-16 providing about 95% of the measurements. The authors found significant variability in more than 55% of the monitored sources.[12]