Observations By The VLBA
The Very Long Baseline Array usually makes radio observations at wavelengths from three millimeters to 28 centimeters, or in other words, at frequencies from 1.2 gigahertz to 96 gigahertz. Within this frequency range, the VLBA observes in eight different frequency bands that are useful for radio astronomy. The VLBA also makes observations in two narrow radio bands below one gigahertz that include spectral lines produced by bright maser emissions.
The use of the VLBA can be scheduled dynamically, and its sensitivity can be improved by a factor of five by including other radio telescopes such as the Very Large Array (VLA) in New Mexico and the Green Bank Telescope in West Virginia with the VLBA.
The VLBA radio telescopes are located at:
North Liberty Fort Davis Los Alamos Pie Town Kitt Peak Owens Valley Brewster Green Bank VLA VLBA locations (red) and HSA locations (blue) in the contiguous United States| Toponymy | U.S. state | Geographic coordinate system | |
|---|---|---|---|
| St. Croix | U.S. Virgin Islands | 17°45′23″N 64°35′02″W / 17.75652°N 64.58376°W / 17.75652; -64.58376 | SC |
| Hancock | New Hampshire | 42°56′01″N 71°59′13″W / 42.93362°N 71.98681°W / 42.93362; -71.98681 | HN |
| North Liberty | Iowa | 41°46′18″N 91°34′27″W / 41.77165°N 91.574133°W / 41.77165; -91.574133 | NL |
| Fort Davis | Texas | 30°38′07″N 103°56′41″W / 30.635214°N 103.944826°W / 30.635214; -103.944826 | FD |
| Los Alamos | New Mexico | 35°46′56″N 106°15′20″W / 35.78233°N 106.25568°W / 35.78233; -106.25568 | LA |
| Pie Town | New Mexico | 34°18′04″N 108°07′09″W / 34.30107°N 108.11912°W / 34.30107; -108.11912 | PT |
| Kitt Peak | Arizona | 31°57′23″N 111°36′44″W / 31.956253°N 111.612361°W / 31.956253; -111.612361 | KP |
| Owens Valley | California | 37°13′54″N 118°16′38″W / 37.23176°N 118.27714°W / 37.23176; -118.27714 | OV |
| Brewster | Washington | 48°07′52″N 119°41′00″W / 48.13117°N 119.68325°W / 48.13117; -119.68325 | BR |
| Mauna Kea | Hawaii | 19°48′06″N 155°27′21″W / 19.80159°N 155.45581°W / 19.80159; -155.45581 | MK |
Four other sites are brought online for as much as 100 hours per four-month trimester. In this configuration, the entire array is known as the High-Sensitivity Array. These sites, with coordinates, are as follows:
Mauna Kea Arecibo Effelsberg VLBA locations (red) and HSA locations (blue) around the world| Toponymy | State | Geographic coordinate system | |
|---|---|---|---|
| Arecibo | Puerto Rico | 18°20′36.60″N 66°45′11.10″W / 18.3435°N 66.753083°W / 18.3435; -66.753083 | AR |
| Green Bank | West Virginia | 38°25′59.24″N 79°50′23.41″W / 38.4331222°N 79.8398361°W / 38.4331222; -79.8398361 | GB |
| Very Large Array | New Mexico | 34°04′43.75″N 107°37′05.91″W / 34.0788194°N 107.6183083°W / 34.0788194; -107.6183083 | Y27 |
| Effelsberg | Germany | 50°31′30″N 6°53′00.3″E / 50.525°N 6.883417°E / 50.525; 6.883417 | EB |
Read more about this topic: Very Long Baseline Array
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