For years, astronomers involved with the Vera C. Rubin Observatory have said that their purpose is nothing less than creating the greatest cosmic movie ever made.
Now, more than a decade after construction of the observatory began on a Chilean mountaintop, the first test frames of that movie are in.
Those images, released to the public on Monday, show much more than an arresting new look at the universe. They are a turning point in how humanity’s exploration of the universe will be conducted.
The Vera C. Rubin Observatory features a wide field telescope that can observe a region of sky 45 times larger than the full moon in area. Light entering the telescope bounces off the ring-shaped primary mirror, up to a convex secondary mirror and then back down to a third reflecting surface embedded in the first. From there, it converges on a series of lenses that guide it into a 3.2-gigapixel imager that is the world’s largest camera.
MURAT YÜKSELIR / THE GLOBE AND MAIL, SOURCE:
VERA C. RUBIN OBSERVATORY
The Vera C. Rubin Observatory features a wide field telescope that can observe a region of sky 45 times larger than the full moon in area. Light entering the telescope bounces off the ring-shaped primary mirror, up to a convex secondary mirror and then back down to a third reflecting surface embedded in the first. From there, it converges on a series of lenses that guide it into a 3.2-gigapixel imager that is the world’s largest camera.
MURAT YÜKSELIR / THE GLOBE AND MAIL, SOURCE:
VERA C. RUBIN OBSERVATORY
The Vera C. Rubin Observatory features a wide field telescope that can observe a region of sky 45 times larger than the full moon in area. Light entering the telescope bounces off the ring-shaped primary mirror, up to a convex secondary mirror and then back down to a third reflecting surface embedded in the first. From there, it converges on a series of lenses that guide it into a 3.2-gigapixel imager that is the world’s largest camera.
MURAT YÜKSELIR / THE GLOBE AND MAIL, SOURCE: VERA C. RUBIN OBSERVATORY
Even those who are used to explaining the observatory’s scientific goals are finding themselves enthralled by the wonder of it all.
“It’s really an ‘oh-wow’ moment,” said Clare Higgs, a Canadian astrophysicist who joined the U.S.-led project three years ago as an outreach specialist.
“We have heard for so long that Rubin is going to be an amazing observatory,” she said. “And we know it has so much groundbreaking engineering, and the largest camera ever built.”
But seeing the data in real life, Dr. Higgs said, has brought home what the milestone means to her field.
“I’m really excited for the world to see that,” she said. “And then to know that this is just the beginning. It’s just the first taste.”
As a way to help frame the dawn of a new era, those involved in the observatory’s first campaign have chosen as their initial targets subjects that are familiar to backyard astronomers and are known by common nicknames rather than by catalogue numbers.
But they have never been seen like this before.
In one view, two billowing cauldrons of ionized gas known as the Lagoon and Trifid nebulas sprawl across a crowded section of our Milky Way galaxy more than 4,000 light years from Earth. These are star-forming regions, where tendrils of dark dust hide new solar systems in the making.
Another selection shows a pair of close-ups from a large view of the Virgo cluster of galaxies. Located some 65 million light years away, each elongated blob of light is a separate galaxy containing billions of stars. Held together by their mutual gravity and by a surrounding halo of invisible dark matter, they are the largest concentration of mass in our cosmic vicinity.
Another section of the Virgo cluster shows faint bridges of matter that extend from the brightest galaxy in the field and that hint at the gravitational tug of war between galaxies.NSF-DOE Vera C. Rubin Observator/Supplied
Both exhibit a degree of visual splendour that is almost surreal when compared to how these objects are normally seen.
Reproductions of those images for this story are a merest hint of the quantity and quality of information the observatory’s 3.2 gigapixel camera can take in. To display just one image from the camera, reproduced at full size, would require an array of 400 ultrahigh-definition (4K) television screens.
It’s this staggering capacity that allows the observatory to see both very wide and very deep at the same time. Until now, astronomical telescopes have had to trade one for the other – either broadening out to take in more of the sky at the expense of detail, or narrowing in to capture fine features within a tiny region.
“The design of this telescope means that we get to have our cake and eat it, too, and I just don’t think we’re prepared for what that means,” said Renée Hlozek, an associate professor at the University of Toronto and a program lead with Canada’s contribution to the project.
The result is a telescope that is ideal for uncovering the distribution and influence of dark matter, a mysterious substance that emits no light but that accounts for about 85 per cent of the mass of the universe.
Astronomer Vera Rubin uses a measuring device at the Carnegie Institution of Washington in the 1970s. Ms. Rubin, the telescope’s namesake, was a pioneering observer who uncovered key evidence for the existence of dark matter, an unidentified substance that makes up 85% of the mass in the universe.Carnegie Institution of Washinton/The Associated Press
Starting in the 1960s, American astronomer Vera Rubin provided compelling evidence for the existence of dark matter based on the way it influences the rotation of spiral galaxies.
Now the telescope that is her namesake will study dark matter across the universe as a whole, by using a technique called “weak gravitational lensing.” It is a way of using subtle distortions in the shapes of distant galaxies to measure the gravitational influence of the dark matter threading its way through the cosmos like a vast interconnected web.
This, in turn, can also be used to examine the behaviour of dark energy, an even less understood phenomenon whose presence is causing the expansion of space to accelerate.
In combination, the two phenomena drive the evolution and fate of the universe. What the new observatory is poised to do, Dr. Hlozek said, is measure both with enough precision to determine which competing cosmological theories are better at explaining them, and which fail to do so.
“We’re entering this phase where there’s going to be so much data that you begin to rule out things,” she said.
Rubin also has an additional superpower that makes it unique among the world’s major observatories. It has the ability to explore what astronomers call “the time domain.”
Because its giant camera can capture so much light so quickly, it is expected that it will image the entire sky available to it every few nights. These repeated surveys can then be assembled into a massive, time-lapse view of the cosmos that will begin later this year and run at least a decade.
Anything that changes in position or brightness, from asteroids whizzing by our planet to supernovas exploding in the distant universe, will be spotted by a system that compares every picture of the sky it takes to a picture of the same area it took previously.
In effect, the idea of the universe as a giant ocean full of unknowns which individual telescopes can dip into like fishermen casting their lines is coming to an end. In its place is an ocean rendered transparent by a giant surveillance tool that will see everything within its reach across a 10 year swath of time.
“It means that we’ll discover a lot of objects that we know we should be there, that we think might be there, but that we haven’t found,” Dr. Hlozek said. “The places where something can hide cosmologically are going to rapidly decrease.”
Making all of this possible requires a vast data pipeline and a network of “alert brokers” to inform the research community of the flood of discoveries the telescope picks up.
“Things that are one-in-a-million events – we’ll find them because there are lots of one-in-a-million events when you’re thinking on the scale of billions,” Dr. Higgs said.
The need to deal with so much data is part of what has allowed Canada to make in-kind contributions to the project in the form of high-performance computing and a platform for the global research community to access the observatory’s data once they become public.
Stephen Gwyn, a science data specialist with Canada’s Herzberg Astronomy and Astrophysics Research Centre in Victoria, is among those leading the effort. He said the observatory is set to realize its promise because of how precisely its measurements are calibrated across a sweeping field of view and across time.
“Knowing exactly how bright a star is is one thing; knowing how bright 20 billion stars are is a much more complex problem,” Dr. Gwyn said. “What they are doing is going to be the best by a significant margin at getting the brightnesses of things exactly right.”
The Vera C. Rubin Observatory is located on the summit of Cerro Pachón, a mountain in the Coquimbo Region of northern Chile.NSF-DOE Vera C. Rubin Observator/Supplied
Before any of that was possible, the observatory and its 8.4 metre telescope first had to be conceived – jointly funded by the National Science Foundation and the U.S. Department of Energy – and built on Cerro Pachón, a mountain in the Chilean Andes where astronomers have found some of the best viewing conditions on Earth.
“The location is majestic,” said Alison Rose, a Canadian filmmaker who has been documenting the observatory’s construction since 2017. What has been most striking about the project, she said, is the fundamental humanity of it, as teams of scientists, engineers and builders, working across continents and cultures, have assembled something of unprecedented capability.
Speaking to The Globe and Mail from Chile, Ms. Rose said that her years of witnessing the effort and coming to know those at the heart of it have left her with an indelible take-away: “It is important to try and do the hardest thing you can do.”
In April she was present the night the telescope’s optics were turned on the sky for the first time. Since then the project has shifted rapidly from a construction site to a working research facility, leading up to the first public image release, with watch parties organized for Monday morning at 11 a.m. ET when the images will be livestreamed during a news conference in Washington.
One such party will be at the University of Toronto, Dr. Hlozek said. Another is planned at the University of Waterloo, where a team of researchers has been working with the Rubin Observatory for several years.
Among them is Liza Sazonova, a postdoctoral research fellow who is preparing to work with Rubin Observatory data to study colliding galaxies.
“We have no idea what we’re going to see,” Dr. Sazonova said as she considered the flood of new data that will soon be heading her way. “But we know we’re going to look at the sky differently.”
The Vera C. Rubin Observatory in Chile beneath the glittering band of the Milky Way.NSF-DOE Vera C. Rubin Observatory/H. Stockebrand/Supplied