3 Key Challenges in Building Canada’s Largest Telescope

Ever since its establishment by brothers Doug and Larry Kenyon Greyback in 1983, the team at British Columbia based Greyback Construction have taken on a range of interesting projects across the commercial, industrial, institutional and residential sectors throughout Western Canada.

Yet the one for which the firm broke ground on January 23 is truly unique: building what will be Canada’s largest ever telescope and the first research telescope to be constructed in the country in more than 30 years.

Upon completion (around April or May), the CHIME telescope, based at the Dominion Radio Astrophysical Observatory in Penticton, B.C, will have a footprint larger than six NFL hockey rinks and will boast a 100-metre-by-100-metre collecting area filled with 2,500 low-noise receivers built with components adapted from the cell phone industry.

Part of an $11-million Canadian Hydrogen Intensity-Mapping Experiment (CHIME), the radio telescope will ‘listen’ for cosmic wave sounds and help scientists understand why the universe has expanded rapidly.

The receivers referred to above will, collectively, scan half of the sky each and every day, with signals collected by the CHIME telescope to be digitally sampled nearly one billion times per second and then processed to synthesize an image of the sky.

Hardly surprisingly, the unique nature of the project has thrown up some interesting challenges with regard to construction.

In recent correspondence with DesignBuild Source, Greyback Construction’s Mike Jereb outlined three key areas:

1) Accuracy.

Given a requirement that the telescope needs to face due north, the nature of this project is such that there will be no room for error.

In order to combat this, Greyback placed four survey monuments at north, east, south and west, which is allowing them to rely on a permanent point rather than a typical batter board or pin.

Also, there will be no margin for error when the structural steel is embedded as the embeds must be placed according to the monuments.

2) Historic sensitivity.

A second area of challenge revolves around the historic sensitivity of the area, with the potential for discovering native artefacts high on the list of concerns.

In order to manage this, Greyback had monitors on site to review all loads of soil which were removed. Also, rather than re-grading the land as initially planned, the firm decided to excavate the pad footing locations only in order to minimise land disturbance.

3) Communication.

Finally, Jereb says communication is an issue as no cell phones or radio wave transmissions are permitted on the property, a challenge he says makes ensuring that everyone involved is clear about what needs to be constructed and achieved especially important.

Certainly, the researchers behind the project at the University of British Columbia are excited.

“We plan to map a quarter of the observable universe” Professor Mark Halpern, UBC astrophysicist and the project’s principal investigator says, adding that data collected by CHIME will help the researchers understand the history of the Universe and in turn how dark energy has driven its expansion.

“This is an ambitious, made-in-Canada endeavour.”

Co-investigator and fellow UBC astrophysicist Kris Sigurdson echoes Halpern’s enthusiasm, saying the recent discovery that the rate of expansion of the universe is increasing rather than slowing down has necessitated a re-examination of basic assumptions about what the universe is made of.

As builders, Jereb says the Greyback team shares the researchers’ enthusiasm.

“Everyone is very excited, the big reward will be what DRAO is able to achieve in mapping the universe” he says.

“For Greyback to be involved is a privilege and a new challenge which is what we are all about.”

By Andrew Heaton