Rabu, 17 November 2021

Things finally looking up for DIY astronomers - CBC.ca

In a rocky field off a private road halfway between Perth and Smiths Falls, Ont., three amateur astronomers gaze skyward, looking for the next big thing. 

They're not peering through telescopes — at least not the kind you're probably picturing.

Instead, they use cast-off satellite dishes to detect and translate the radio waves that all warm celestial bodies emit — objects that are often invisible to optical telescopes.

"Our eyes are good for optical wavelengths — we can see colours and that sort of thing — but the universe is actually much more complicated than that," explained Marcus Leech, current president of the Canadian Centre for Experimental Radio Astronomy (CCERA).

"Radio telescopes are just telescopes for radio waves. So it's just another way of looking at the universe."

We're doing big science on an extremely modest budget.- Doug Yuill, CCERA

Interstellar space is full of dust that can obscure our optical view of stars, planets, galaxies and other objects, Leech said.

"A lot of optical observations can't see these objects behind the dust. Radio astronomy sees them just fine."

CCERA members Gary Atkins, left, Leech, centre, and Doug Yuill inside the donated trailer that's the new nerve centre of their observatory. Last December, the astronomers found themselves homeless due to 'an unfortunate confluence of both corporate and municipal politics,' Leech says. (Francis Ferland/CBC)

Grassroots science

This is grassroots science at its least glamorous. There are no white lab coats or state-of-the-art observatories.

Instead, Leech, along with colleagues Gary Atkins and Doug Yuill, spent their spring and summer mixing and pouring concrete, salvaging discarded satellite dishes and retrofitting the donated trailer that now serves as their operation's nerve centre — all in a race against the onset of winter.

"We had to switch our focus to just surviving, finding a new place to be and then setting up that new place," Leech said.

WATCH | Astronomers ready to stargaze again after eviction from former home:

DIY astronomers ready to stargaze again after being evicted from former Smiths Falls home

7 hours ago
Marcus Leech, president of the Canadian Centre for Experimental Radio Astronomy, says the organization is getting settled after finding a new home in Rideau Ferry. The group of amateur astronomers uses cast-off satellite dishes to detect radio waves that come from celestial bodies. 2:31

CCERA is a non-profit association that "supports education and research in radio astronomy techniques and applications targeted at smaller institutions and interested individuals," its website says. It has an advisory board made up of some of the world's top astronomers, who provide advice on an ad-hoc basis, and publishes its findings on its website.

It formed after the Canadian Space Agency decided in 2013 to dismantle an 18-metre dish that the astronomers were using in Shirleys Bay, a conservation area on the Ottawa River. They moved their operation to the Gallipeau Centre in Smiths Falls, in eastern Ontario, but last December — owing to what Leech describes as "an unfortunate confluence of both corporate and municipal politics" — they found themselves homeless once again.

After finding a plot of flat, clear land, the group spent the spring and summer erecting four parabolic dishes that act as radio telescopes. A fifth, larger dish will likely be installed next year. (Francis Ferland/CBC)

So the astronomers found a 15-hectare plot of flat, clear land in the small community of Rideau Ferry, struck a long-term "access arrangement" with the owner and in March began moving in. Now, eight months later, they're nearly ready to roll.

Having an unobstructed view of the sky is as essential for radio astronomy as it is for optical astronomy, Leech said, because even trees emit microwave radiation that can interfere with their observations. Likewise, being "in the middle of nowhere" narrows the chance of man-made interference of all kinds.

The astronomers have installed four parabolic satellite dishes near their trailer: one hydrogen spectrometer, painted like a big yellow happy face, and three more dishes honed in on fast radio bursts, or FRBs, a phenomenon Leech describes as the current "darling" of the astrophysics community.

A fifth, larger dish is piled in pieces nearby, waiting to be assembled and mounted, likely next year.

Anomalies on a graph can indicate the presence of a celestial object. 'We look for squiggly lines on graphs, basically, and we get excited about those,' Leech says. (Francis Ferland/CBC)

The radio signals they're trying to capture are "insanely weak," Leech said — in fact, the combined energy from all of the signals detected since the discovery of radio astronomy in the 1930s "would keep a candle going for maybe half an hour. That's it."

While there are complex networks of radio telescopes capable of translating those invisible signals into sky maps and other images, CCERA's current setup is not.

This image from the Virginia-based National Radio Astronomy Observatory shows spiral galaxy NGC 4254 in the Virgo Cluster. It combines radio data from the Atacama Large Millimeter/submillimeter Array (ALMA) showing molecular gas in red and orange, and optical imagery captured by the Hubble Space Telescope showing stars in white and blue. Few radio astronomy observatories are capable of producing this kind of image. (ALMA (ESO/NAOJ/NRAO)/S. Dagnello (NRAO))

"We look for squiggly lines on graphs, basically, and we get excited about those," Leech said.

To the passionate radio astronomer, those anomalies are just as energizing as any pretty picture.

"The first time you see that squiggly line is actually really exciting, because you realize that ... this thing happened 750 million years ago, and today it's making a little squiggly line on your instrument — and that can be exciting for the right kind of person, I guess."

Leech developed a passion for radio astronomy in high school. Now semi-retired after a career in high-tech, he devotes much of his time to his original interest. (Francis Ferland/CBC)

Lofty goals on shoestring budget

Leech said he's been "obsessed" with radio astronomy since he was in high school — though he was lured into the high-tech world, spending nearly 20 years at Nortel. Now semi-retired, he's returning to his first passion.

This may be a shoestring operation, but CCERA's goals are as lofty as the objects they're trying to observe.

"I think being the first to discover the radio emissions of a new supernova before the optical guys see it, that would be a real feather in our cap," Leech said. "Our first confirmed FRB would be a major, major achievement for an amateur effort, and so that's our hope."

Happy now? The astronomers decided to give their hydrogen spectrometer a new look at their new home. (Francis Ferland/CBC)

But since their eviction from their former base in Smiths Falls, CCERA's main focus has been on earthly survival, not the stars.

Historically, the group has relied on donations, as well as a partnership with Carleton University's undergraduate astrophysics program. The COVID-19 pandemic cancelled in-person classes, however, shutting down that source of revenue.

Leech estimates the group needs about $20,000 a year to operate. For now, they're scraping by however they can. Often, that means reaching into their own pockets.

"We're doing big science on an extremely modest budget," Yuill said.

But they know the payoff could be astronomical, scientifically speaking at least.

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2021-11-17 09:00:00Z
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