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The Return to Service of the HartRAO 26m Telescope
Michael GaylardHartRAO
South polar shaft bearing failed 2008 October 03
Diagram of NASA antenna similar to HartRAO's
A-frame to support telescope during bearing replacement
HartRAO 26m telescope repair - pouring foundations for A-frame April 19
Components at Tass Engineering, Johannesburg May 26
Ludwig Combrinck measuring the polar shaft position May 27
Placing the A-frame box-beam on the concrete bases June 10
Preparing the A-frame legs June 18
First A-frame leg hanging from collar around polar shaftJune 21
Bracing the hour angle gear wheelJune 23
Last A-frame leg installedJune 24
Inserting the pin locking the A-frame leg to the box-beam June 24
Welding A-frame base to box-beam June 29
200-ton hydraulic jack lifts the telescope June 30
Polar shaft end cap puller in place July 01
Removing the polar shaft end capJuly 02
Failed bearing exposed July 02
Extracting fragments of shattered bearing July 02
Arc-gouging to extract remains of bearing July 06
Preparing polar shaft end cap for re-installation July 13
The new bearing is in July 15
Re-installing the polar shaft end cap July 15
Removing the A-frame July 16
The telescope drives West for the first time 2010 July 20
Testing the limits July 22
First light – testing the telescope pointingJuly 22
First pulsar observation – Vela pulsar July 23
First spectroscopy – water vapour in Orion July 23
26m and 15m (XDM) – both observing the Vela pulsar July 23
Vela pulsar glitches after 4 years – on July 31 at 21h 15m SASTdiscovered by 15m XDM then 26m
Sarah Buchner
See Astronomers Telegram 2768
Interacting Binary star Circinus X-1radio flares
See Astronomers Telegram 2699
First VLBI after repairICRF astrometry Aug 11
First target of opportunity e-VLBI with the EVN, Sep 30
MAXI J1659-152Zsolt ParagiATEL 2906
e-VLBI to Europeat 1024 Mbps – Nov 23
Target of Opportunity – Crab Pulsar
e-VLBI to Australiaat 512 Mbps – Nov 24
Jonathan Quick
26m Telescope Repair – Key Players and timeline
National Research Foundation – President Albert van Jaarsveld approves motivating the repair, 2009 July 22
Department of Science and Technology – Minister Naledi Pandor obtains funds for the repair
GD Satcom (US) – prime contractors - Tom McClellanStratosat Datacom (SA) – local contractors – Gerhard BothaTass Engineering (SA) – heavy engineeringHartRAO – Pieter Stronkhorst, Antennas and special projectsFirst post-repair observation – 2010 July 22First post-repair VLBI – 2010 August 11 - Jonathan Quick, VLBI Operations Manager