The Vera C. Rubin Observatory's view of the Virgo Cluster, a group of galaxies some 65 million light-years away. With its 3.2 billion-pixel camera, the Rubin Observatory captures extremely detailed photographs. Photo / Vera C. Rubin Observatory, NSF, DOE, the New York Times
The Vera C. Rubin Observatory's view of the Virgo Cluster, a group of galaxies some 65 million light-years away. With its 3.2 billion-pixel camera, the Rubin Observatory captures extremely detailed photographs. Photo / Vera C. Rubin Observatory, NSF, DOE, the New York Times
Smile, universe! It is time for your close-up with the Vera C. Rubin Observatory.
The telescope, more than two decades in the making, will provide a comprehensive view of the night sky unlike anything astronomers have seen before.
The project’s scientists revealed some of the first imagery it releasedtoday.
“Rubin Observatory is the greatest astronomical discovery machine ever built,” Željko Ivezić, the director of construction, said during the presentation revealing the first images.
He noted that for the first time, the number of observed celestial objects will be greater than the number of people living on Earth.
Over the next decade, the imagery will be patched together to create “the greatest movie of all time”, Ivezić said.
The observatory, named after astronomer Vera Rubin, is a joint venture of the United States Department of Energy and the National Science Foundation.
It was built on a mountain in northern Chile in the foothills of the Andes at the edge of the Atacama Desert. The location, high and dry, provides clear skies for observing the cosmos.
The Vera C. Rubin Observatory in Cerro Pachón, northern Chile. Photo / Marcos Zegers, the New York Times
At the news conference today, Ivezić explained that part of Rubin’s powerful capability was that its singular data set would serve many different science goals.
The observatory’s treasure trove of data will allow astronomers to investigate dark energy, a force pushing the universe to expand ever faster, as well as dark matter, a mysterious substance that behaves somewhat like galactic glue.
Closer to Earth, it will identify asteroids that might be on a collision course with Earth.
When asked about what surprises might be hiding in the data, Federica Bianco, Rubin’s deputy project scientist, said that these were unknown unknowns. “It’s really an adventurous horizon,” she said.
Two of the first images show snippets of the Virgo Cluster, a group of galaxies some 65 million light-years away.
In the foreground are bright stars that lie within our Milky Way galaxy.
In the background are many extremely distant galaxies, with a reddish hue, because in an expanding universe, distant objects are moving away at high speeds.
In the middle are galaxies within the Virgo cluster. The blue dots within galaxies are star-forming regions with younger, hotter stars.
A photo provided by the Vera C. Rubin Observatory shows the Trifid and Lagoon nebulas. Photo / Vera C. Rubin Observatory, NSF, DOE, the New York Times
But each snippet shared is but a tiny piece of the full image produced by the telescope.
The level of detail in the Rubin images is impossible to convey on a computer screen or a newspaper page.
As a result, the Rubin team has developed Skyviewer, which lets people zoom in and out of the giant images.
“We needed to make dynamic ways to share the data,” Steven Ritz, a physicist at the University of California, Santa Cruz, and the project scientist for Rubin construction, said in an interview.
“We knew the images were so big that if you zoomed all the way out, it would kind of look like porridge. You wouldn’t see the richness. You had to be able to zoom in.”
With Skyviewer, anyone can carry the cosmos around on a smartphone.
“You can have 6 billion pixels in your pocket,” Ritz said. “It’s really cool.”
Most of the celestial objects do not yet have names, because they are being viewed for the first time.
The software tool allows one to hear the images too.
“We built in an ability to interact, to experience the data, not with your eyes, but with your ears,” Ritz said.
“That matters to some people who, of course, only have a capability with their ears. But I think it’s valuable for everybody.”
Alysha Shugart, deputy manager of the observing specialists' team, inside the Vera C. Rubin Observatory. Photo / Marcos Zegers, the New York Times
Ivezić also showed streaks of asteroids photo-bombing the cosmic images.
The observatory’s software automatically removes them from pictures of the distant universe. It also calculates orbits of the asteroids. In just a few nights of observations, it discovered 2104 new asteroids.
Seven of them are near-Earth asteroids, although none are on a collision course with Earth. The rest are in the main asteroid belt between Mars and Jupiter.
Another image showed a riotously pink view of the Trifid and Lagoon nebulas.
The two sprawling clouds of dust and gas, thousands of light-years away from Earth in the constellation Sagittarius, have been photographed often by both amateurs and professional astronomers.
More powerful instruments have taken more detailed photos, but with their narrow field of view, they only see a small slice of the scene.
The blue regions are lit up by light from young, hot stars and scattered by dust, said Clare Higgs, an outreach specialist working for Rubin. The pinkish colours most likely come from emissions of excited hydrogen atoms, and the dark tendrils are lanes of dust.
Construction of the Rubin Observatory began a decade ago. The completed telescope recorded its first bits of light on April 15.
The telescope mount assembly at the observatory in Cerro Pachón, Chile. Photo / Marcos Zegers, the New York Times
Victor Krabbendam, the project manager who was in the control room that night, said that was not necessarily the plan for that night.
“We had literally spent the entire day unsure that we would be able to even try,” he recalled during an interview.
Fuses needed to be replaced. A camera had not been turned on yet. But those problems were resolved. After a shift change, the next team started preparations for switching the telescope on.
“It was, in a way, kind of sudden,” Krabbendam said. “And then somebody says, ‘OK, yeah, we’ve taken an image.’”
Then a pause as the computers processed data from the camera. “And then it was on the screen,” he said.
Krabbendam said he reacted little to that. “At the moment, it was, this is what we do every day,” he said. “It’s just always solving problems, and things work and they don’t work.”
The first image was not perfect. Instead of dots of light, stars showed as doughnuts. But seeing doughnuts rather than smeared blurs meant the mirrors were not far out of alignment.
After a few adjustments, the doughnuts turned into dots.
“This period of time between that first image and this very clear image you see right here was less than a few minutes,” Alysha Shugart, deputy manager of the observing specialists team, said during a presentation to reporters at the observatory in May. “And this was our night of first photon.”
A photo provided by the Vera C. Rubin Observatory shows a small piece of a much larger image of the Virgo Cluster, a group of galaxies some 55 million light-years away. Photo / Vera C. Rubin Observatory, NSF, DOE, the New York Times
Since then, engineers and scientists at Rubin have been working to calibrate and fine-tune the complex telescope. Science operations and the 10-year survey will kick off in earnest later this year.
Rubin is far from the largest telescope in the world, but it is a technological marvel.
The main structure of the telescope, with a 8.5m-wide primary mirror, an 3.3m-wide secondary mirror and the world’s largest digital camera, floats on a thin layer of oil. Magnetic motors twirl the 300-tonne structure around — at full speed, it could complete one full rotation in a little more than half a minute.
Its unique design means Rubin can gaze deep, wide and fast, allowing the telescope to quickly pan across the sky, taking some 1000 photos per night.
By scanning the entire sky every three to four days for 10 years, it will discover millions of exploding stars, space rocks flying past and patches of warped space-time that produce distorted, fun-house views of distant galaxies.
The coating chamber of the primary and tertiary mirrors. Photo / Marcos Zegers, the New York Times
“You’ve not seen the whole thing, all captured at once at this depth with so many objects there,” Ritz said. “That, I would point out, is new. And just how pretty it is.”
