Radio waves from space
Two federally funded projects put Canada at the forefront of cosmic radio wave research and provide a better understanding of the dark energy driving the universe’s expansion.
What a wonder our universe is! Take light, for example. We can see only a tiny band of the electromagnetic spectrum. At the shorter end are ultraviolet light, X-rays and gamma rays, while at the longer end are infrared light, microwaves, radar and radio. Our atmosphere absorbs many of these wavelengths, preventing them from reaching us. But the wavelengths we do see, as well as radio waves, reach us with little reduction. While limited in wavelength, our colour vision is wonderfully matched to the available light on Earth – an amazing gift from our Creator!
Atmospheric absorption is one reason space telescopes are so attractive to scientists. The striking images from the new nine-billion-dollar James Webb Space Telescope are collected in the near-infrared range, a wavelength that does not penetrate our atmosphere. The Canadian Space Agency is a partner in this telescope, but it clearly cannot afford science on this scale.
CHIME and CHORD
Instead, Canada has focused on the longer wavelengths that pass through the atmosphere, especially radio wavelengths. A Canadian coalition has built large (but much less expensive) on-the-ground radio wave detectors near Penticton, B.C. in the Okanagan Valley, protected by hills from earth-generated radio waves. The first one, opened in 2017 and named CHIME (Canadian Hydrogen Intensity Mapping Experiment), is a fixed detector built for 16 million dollars. It can look back in time 11 billion years and consists of a series of half-pipe reflectors and a lot of computer technology to process the signals. One mystery it has explored is fast radio bursts, which remain unexplained to this day.
CHIME is limited because of its fixed design, so now at the same site, a new radio telescope consisting of 512 six-meter dishes called CHORD (Canadian Hydrogen Observatory and Radio-transient Detector) is being built. CHORD will greatly increase our ability to measure radio waves from more of the sky, at a cost of 23 million dollars – small change in the big-science arena. In addition, two outrigger stations in California and West Virginia will enable more precise localization of fast radio bursts. Measuring the 21-centimetre hydrogen emission line will allow us to map the universe and provide a better understanding of the dark energy driving its expansion.
Worth it?
CHIME and CHORD are examples of how Canada, with limited resources, is doing world-class science by carefully selecting areas that are open to us. The SNOLAB facility, built in a deep underground mine near Sudbury to study dark matter and neutrinos, is another example of leveraging what we have to do world-class science.
Building a better understanding of God’s creation through science has brought us many unexpected benefits.
As Christians, we wonder if our government is spending our tax dollars wisely. There are so many needs today, and we hope justice and mercy will play their part in these difficult decisions. But building a better understanding of God’s creation through science has brought us many unexpected benefits, and we can be thankful that these science projects are carried out in a stewardly way.
