Imagine if space was your lab. Infinite possibilities of places and things to discover. Imagine then, not having the means to share your discoveries with the world.

International Year of Astronomy Because they capture the public’s imagination, compelling astronomical images serve as potent ambassadors for astronomical researchers. Never has this been so apparent as this year, the International Year of Astronomy (IYA2009). This year promises a global celebration of astronomy and its contribution to society and culture, with strong emphasis on education, public participation and the involvement of young people, and with events at national, regional, and global levels. Thousands of people in more than 135 countries are already involved, forming the world’s largest astronomy network. IYA2009 represents astronomy as a peaceful global scientific endeavour that unites astronomers in an international, multicultural family of scientists, working together to find answers to some of the most fundamental questions humankind has ever asked. www.astronomy2009.org

Enter Brent Carlson, Project Engineer for the Expanded Very Large Array (EVLA) Correlator Project, Penticton, B.C., and Stéphane Claude, Team Leader, Millimetre Instrumentation, Project Engineer, Band 3 Receivers Project for the Atacama Large Millimetre Array (ALMA) Radio Telescope, Victoria, B.C. Both work for the National Research Council Herzberg Institute of Astrophysics (HIA).

It is the job of these two engineers to understand the requirements of astronomers and develop systems to deliver them. They both design new instrumentation and technology for the Canadian astronomy community, and in particular, the radio astronomy field. Some of what they design allows us to see further and further into space, and in greater, more colourful detail.

“It’s so exciting and the vast majority of people have no idea what astronomers do,” says Carlson. “Astronomers don’t just look at the sky and make pretty pictures. That’s part of it but the research and some of the exciting things that are going on are eye-opening.”

Carlson’s work is on the EVLA, the world’s flagship radio telescope comprised of 27, 25-metre antennas in New Mexico. It was constructed in the 1970s and has been operational since 1980. A proposal to upgrade its bandwidth receiver capability began in 1995, with the Americans looking for partners to help fund the $100 million upgrade project.

The entire project consists of upgrading the existing antennas, receivers, and adding a fibre optic transmission system, which the U.S. has completed. Canada’s contribution is a central signal processing system called a correlator, to process all the signals that produce data that the scientists then use to make images of the radio sources they’re observing. They call it the heart of the telescope and a big part of the science capability of the instrument is determined by what the correlator capabilities are. Canada has a significant track record in building correlator systems, so a collaboration was formed.

Claude’s millimetre instrumentation lab at the HIA in Victoria is one of the few facilities in the world with expertise in superconducting detector technology for millimetre waves. This technology employs tiny switches about 50 times smaller than the width of a human hair, operating at liquid Helium temperatures of -269 C to detect and amplify the incredibly faint whispers of radiation that reach Earth from the remotest parts of the cosmos. Claude’s lab works with a large team of engineers and support staff led by project manager Keith Yeung, to develop receivers for one of ALMA’s frequency bands (Band 3). Canada will supply receivers of unprecedented sensitivity for the 3-millimetre wavelength band —the ALMA Band 3 Receivers. Funding is supplied by the NRC and the Canada Foundation for Innovation. These receivers are of paramount importance to the project because they will be used not only for many science applications but also for final adjustment of the antenna panels and for regular calibration of the array during operations. The team will ultimately deliver 73 receivers to ALMA by 2011. At press time they had completed 18.

Carlson says the main benefit of these collaborative arrangements is the increased telescope time Canadian scientists will receive. Major world observatories typically run a “you get what you pay for” system, where for example, if you put in five per cent of the dollars, you get five per cent of the observing time. By collaborating on the EVLA project, Canada is leveraging its position.

“I think our total contribution is $30 million for ALMA, and ALMA is nearly a $1 billion telescope,” says Carlson. “That would normally buy us very little observing time but by doing the EVLA correlator project in conjunction with the Band 3 receivers, we have an agreement that if our scientists put in good observing proposals, they compete on par with American scientists for observing time so it potentially buys us more time for our scientists.”

	Brief History of Canadian Astronomy Ninety years ago, the government built the Dominion Astrophysical Observatory. For a brief time, it was the largest optical telescope in operation in the world. Since then, Canada has secured a place among world leaders in astronomy through scientific achievement, international collaboration, and technological and industrial development. Following major reviews of Canadian astronomy in the 1960s, the National Research Council of Canada (NRC) was assigned responsibility for the federal government’s observatories and formed the Herzberg Institute of Astrophysics (HIA) to carry out that mandate. HIA operates from two historic sites: The Dominion Astrophysical Observatory (DAO) in Victoria and the Dominion Radio Astrophysical Observatory (DRAO) in Penticton. Both sites have functioning telescopes continuously used for research programs, conducted mainly by external users. These domestic facilities are also used as test beds for new instrumentation concepts. The sites have considerable supporting infrastructure for instrumentation development and for scientific technological research and serve as Canada’s national laboratories in the field, attracting numerous collaborators, students and post-doctoral fellows.. www.hia-iha.nrc-cnrc.gc.ca

According to Carlson, the VLA is listed as one of top five telescopes of all time. (The others are Galileo’s homemade spyglass, the Hale Telescope in California, the Hubble Space Telescope, and the Chandra X-ray Observatory.) Carlson feels the pressure and says failure is not an option. “It’s a very visible radio telescope and if we falter it’s very visible so there’s a lot of pressure.” Assuming everything is a success, it will mean a large number of papers and science can be done using this system over the next 20 years.

Electromagnetic interference is a daily challenge for Carlson and Claude. Power transmission lines, cell phones, microwaves, and computers can all interfere with sensitive telescope equipment. The HIA lab Carlson works at is located in the White Lake Basin near Penticton. The secluded location is perfect for operating the telescopes, however, the lab is under increasing pressure from the spread of modern technology such as wireless devices and potential land developments in the surrounding area. “Electromagnetic interference is one of those things that there is no silver bullet,” he says. “You have to try to keep it as quiet as you can, and there are mitigation techniques but interference levels are increasing with time and there’s pressure from the local community.”

Interference must be kept to a very minimum within the buildings as well. Computers are in shielded boxes and the lab is located inside a double-shielded screened room in the central core of the building. Rooms are also temperature-controlled and ESDprotected (from electrostatic discharge). “We have an interlock system so you go in and you’re wearing an ESD coat, ESD shoes and you’re tested before you go in and we maintain a certain humidity level in there because we want to make sure when we deliver the system that we’re shipping hardware that’s in good working condition and doesn’t have potential defects from ESD,” says Carlson. “In fact, we demanded that the end users set up a similar system to protect the boards because if it does get damaged and eventually fails, it’s a fairly significant process to take the board out, remove all the hardware and put it through a rework to replace the chip.”

The correlator itself is housed in a special-purpose computer room with cooling and controlled dust and humidity settings. Carlson says the correlator’s size and computing power pushes the limits of circuit board technology. “It’s about 50 feet on the side and there are 16 racks in total. Each rack holds 16 large circuit boards… each of these chips can have up to 1,000 solder points and in our system, on the most complex board, there are about 150 of these chips, some with 256 pins, some with almost 700 pins. There’s 11,000 components on a board, 100,000 solder points and it’s all got to be working flawlessly to get real science out of the telescope.”

The complexity of the system adds a further challenging dimension. “We write specifications for various protocols, for various interfaces, the engineer does the design, the software has to tie in to all this, it’s a fairly large software effort in all this and just getting it all working is quite challenging,” Carlson adds.

Claude experiences similar challenges. The receiver uses a superconducting diode, which must be cooled. This is done with a cryostat, so all tests involve cryogenics and vacuum technology.

Electronics, radio technology, mechanical and optics are involved as well. “The challenge is to make sure all of the specifications and needs are met across these different fields,” he says.

The current challenge the Band 3 team faces is meeting the schedule while still meeting performance targets. Each receiver goes through a battery of 15 tests over a two-week period before it’s submitted to the lab that will integrate the receiver and then send it to the site in Chile. The program relies on careful measurements and lots of documentation.

“We had a three-year technology development phase during which we went from conceptual design to a prototype,” says Claude. “And then we went through a preproduction series. We had to design the receiver but then we had to design the test procedures… testing it was as long as designing it.”

Both engineers are also working on long-term projects that take about 10 years to go from start to finish. With the rapidly changing face of technology today, it’s conceivable that things would change along the way, either catching up to a point where it would help the engineers design something they couldn’t previously, or on the other hand, making something virtually obsolete by the time they completed it. Claude is confident his design can stand the test of time.

“I think for this receiver, it was really well advanced when we designed it; it’s really state-of-the-art. Of course there are some points where we could have gone differently in terms of integration of the different components. It’s a balance to get it done or to do more integration of components to make it more efficient but then there is a high risk we might run into trouble for the production because if you integrate things they have to be all perfectly matched. On a prototype it’s OK, but not times 73. We need to ensure it’s mature enough. For this large number we are still very competitive. I don’t have an issue with that.”

How it Works: Band 3 in Simple Language The signals come from so far away, they’re very faint. They’ve been emitted for thousands of years, so they’re very weak and we don’t want to add too much “noise” (like interference on car radio)… The analogy to the radio in your car is a good one: you’ve got the antenna, which is a piece of metal, but in astronomy, it’s a dish. The radio is really what we design. When you tune it, you change frequency bands, so really what we are designing is one channel so we can listen to CBC only with our receiver. To cover the whole frequency range, we have to build different receivers. It’s like having 10 different radios—you use one or the other depending which frequency you want to tune in. - Stéphane Claude, Team Leader, Millimetre Instrumentation, Project Engineer, Band 3 Receivers Project for the Atacama Large Millimetre Array (ALMA) Radio Telescope, Victoria, B.C.

Both Carlson and Claude have more work lined up. Carlson’s team will be moving into a research and development phase for its next project, the Square Kilometre Array. Internationally, the project has been divided it into various areas of research. Not surprisingly, Canada is working on the antenna, receiver and correlator technologies.

“This would be a system that would be orders of magnitude larger than what we’re doing now,” says Carlson. “You want to do things as efficiently and cheaply as possible so we’ll be looking at that for several years before fabrication starts.”

Claude’s plan is to work on the low noise amplifier technology, which is key to astronomy receivers. The amplifier his team developed for Band 3 was subjected to technology transfer to a company in Toronto, which is now producing it under license. “The amplifier field is an interesting one because it’s good for astronomy but it can potentially be useful for some high tech companies,” he says.

Claude has also submitted a couple of proposals for far infrared detectors, which would literally take the team beyond what they’re working on now. “It’s an interesting zone where it’s between the radio field and the infrared field. It’s a new field for detectors but the Canadian Space Agency is interested because it’s part of the electromagnetic spectrum you can’t observe very well from the ground.”

Recent discoveries by Canadians at the top of their astronomy game also continue to fuel the engineers. Last November, an NRC-HIA team of international researchers led by astronomer Dr. Christian Marois, became the first to capture images of three planets circling a star other than the Earth’s sun.

“The discovery by the Canadian scientist actually taking a picture of a planet around a nearby star, that’s hugely significant and it’s falling on the 400th anniversary of Galileo’s first telescope and observing the moons of Jupiter,” says Carlson. “It’s astounding quite frankly. We never thought that would be possible, at least with today’s technology.”