PaST: Primeval Structure Telescope

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Continued Expansion the PaST Prototype in Ulastai (December, 2004)

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Parts for the antennae arrive in boxes and are assembled into structures like that in the foreground.

Several workers in the process of assembling the hundreds of new antennae.
A view of several of the new pods.  Note that the pod in the foreground and the two in the far background have yet to be aligned. 

A view of several pods that have already been aligned to point toward the North Celestial Pole.

In the center, the five-member programming team based in Beijing that designs and manages the correlator.  On the far left is Ue-Li Pen and on the far right is Jeffrey Peterson.

Fall, 2004 Expansion the PaST Prototype in Ulastai (November, 2004)

The new, on-site building which housed supplies and the correlator computers for the array.

A view of one the pods in the expanded array.  Note that a metal mesh is at the base of the pod in order to decrease reflections.  The mesh in the foreground was later placed on the second pod.
A profile view of the pod.  Note that all of the antennae point in the same direction: to the North Celestial Pole (the point on the sky directly above the Geographic North Pole of the Earth).

A closer view of one of the pods, shown here with fiberglass supports rather than metal.  Note that coils of cable are shown, each cut to precise lengths so that the entire array is focused on the North Celestial Pole. 

Expansion of the PaST Prototype in Ulastai (June, 2004)

The materials for the antennae as they arrived in Ulastai from the manufacturer.

Several workers at Ulastai assemble the antennae.
Several workers at Ulastai assemble the antennae.

Here the antennae are put in place in the pod.  Note that all the antennae in this stage of the prototype will be elevated above ground; in the previous stage (background) they were not.
The angle of each antenna is carefully checked so that each is pointing to the North Celestial Pole.


PaST Prototype in Ulastai

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A view of the valley in which the current prototype is located.

A closer view of the valley.  Note that the two of the pods of antennae have been marked. 
One of the seven-element pods in the PaST Prototype located in Ulastai, China.

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Some members of the crew constructing the prototype pause for a photograph.
The output of a single antenna displayed on a signal analyzer.  Note the distinctive and expected fall-off at high frequencies.

The building used to house the correlator and other computer equipment in Ulastai.

In the near-by field, a horse-backed shepherd tends his flock: a common sight in Ulastai.
A map of the sky generated by this prototype.  Note that the white circles denote know source of stellar radio emissions.  The prototype was able to detect the strong sources (larger circles) seen in this picture as dark ripples.