Photo – Page 19 – National Radio Astronomy Observatory

ALMA’s Central Array on the Chajnantor plains

The Atacama Large Millimeter/submillimeter Array (ALMA) sits on the Chajnantor plains nearly 5,000 m above sea level and currently has 66 high precision antennas working together at millimeter and submillimeter wavelengths. There are three different types of antennas (European, North American, and Japanese antennas) found in ALMA that can be distinguished by the design of the wire on the main dish. The European antennas have simple wiring with no pattern underneath it. The wiring touches the edges of the dish and shaped like an X. On the other hand, the wiring of the Japanese antennas do not touch the edges of the dish, are shaped like lowercase-T and have a triangular-like pattern under the end of each wire. The wiring of the North American antennas also appears in the shape of a lowercase-T, however it is larger than the Japanese Antenna’s wiring since it touches the edge of the dish. There is also a triangular pattern found underneath the entire wire of the antenna.

Rainbow Over the VLA

The Very Large Array may sit in the New Mexico desert, but it’s not always dry. Summer monsoons bring much-needed rains to the desert.

Photo of the full moon above an ALMA radio antenna.

Moonrise above North American Antenna at ALMA’s high site

The final North American ALMA antenna, number 25 of 25, rests under a setting Moon after a day of testing at the Operations Support Facility in northern Chile. The North American antennas in the Atacama Large Millimeter/submillimeter Array (ALMA) can be distinguished through two details with the wiring: The wiring touches the edge of the antenna’s dish and has a pattern of triangles underneath it, as you can see in the above photograph.

A photo of a line of VLA antennas underneath a partial moon.

Half Moon over the VLA

The Moon is quite bright and clearly visible at the VLA due to the high contrast of the dark, indigo skies above the Very Large Array in New Mexico.

Photo of ten VLA antennas pointing at a cloudy sky at twilight.

A Cloudy Twilight at the VLA

Clouds linger at twilight over the Karl G. Jansky Very Large Array in its most compact configuration.

Photo of three completed and one incomplete ALMA antennas.

Assembling Japan’s Antennas at ALMA

Pictured is a view of the East Asian telescope assembly area at the ALMA Operations Support Facility in northern Chile in 2008. Four 12-meter telescopes are in various stages of assembly and testing. In the background left looms the North American laydown area and its fully-enclosed assembly area. Since the telescopes are now in place, the assembly areas are no longer in use.

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