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    Extended Very Large Array Radio Astronomy Observatory


    Out in the high plains west of Socorro, NM, is the Extended Very Large Array (EVLA) National Radio Astronomy Observatory. The "Extended" part of the name came into operation last year; the sign has yet be updated. We visited the sites in October 2011. Of particular interest is the method used for moving the massive telescopes.

    vla02  Driving along US-60 45 miles west of Socorro, this is your first view of the facility. 
     Turn down NM-52 toward the observatory and you'll get a closer view of the 27 radio telescopes.  vla05
     vla03  The secret to the observatory is the ability to move the telescopes out along three radial double railroad tracks, each of which is 13 miles long.
     On the day of our visit the telescopes were in their closest-in deployment.  vla09
     vla07 Each telescope has a 82' diameter dish and weighs 230 tons. 
     The telescopes are moved using a large transporter. Out along the radial railroad tracks are preset positions with pedestals. The transport can move the telescope to the pedestals, lower it into position and after it is bolted in place, the transporter lowers a bit and moves away.  vla17
     vla18  Here's a close-up view of one of the two transporters.
     Instead of using track swirches, the transporter can lift and rotate its wheels to move from the main track to the short track to each position. Here the wheels on the left have already been turned.  vla23
     vla24 Now the wheels on the right in the above picture have been lifted in preparation for turning. 
     Here it is in the process of being rotated. vla25 
     vla27  Completing the 90-degree turn, the wheels are lowered back to the tracks.
     This particular telescope was being moved into the Antenna Assembly Bullding for some maintenance.  vla30
     vla31  In position over its pedestals (one on each side and one in front), the telescope will be lowered and bolted down.