The Vera C. Rubin Observatory is set to provide a new perspective on the universe
Olivier Bonin/SLAC National Accelerator Laboratory
The elevation is high above Celopachen, a Chilean mountain towering over 2600 meters. As I ascend the stairs within the dome of the Vera C. Rubin Observatory, I find myself breathing deeply. The atmosphere is cool, serene, and expansive, resembling a cathedral. Then, the entire dome begins to rotate, revealing the vast sky.
Night falls, unveiling an abundance of stars like I’ve never witnessed. The Milky Way shines exceptionally bright, and I can spot two of its satellite galaxies, the Small Magellanic Cloud. Yet, the Rubin telescope steals the show with its massive presence. It boasts the largest digital cameras and lenses in the world, tipping the scales at a staggering 350 tons. As a reflective telescope, it gathers light via a mirror, with its largest mirror measuring 8.4 meters across. The tunnel leading to the summit matches its width at about 8.5 meters.
https://www.youtube.com/watch?v=t2neujuof_g
Despite its immense weight, this telescope can maneuver swiftly, poised to transform our understanding of the solar system, galaxies, and the universe at large. Every three nights, it completes a Southern Sky survey, a feat that previously required weeks or months. Over a decade, Rubin will create a kind of cosmic time-lapse.
“By capturing the sky every three days, we can layer those images to delve deeper,” explains researcher Kevin Rail. “Ten years down the line, we will have explored much more deeply, revealing the universe’s structure,” he states.
A core mission of the observatory involves comprehensively understanding how dark matter influences the cosmos. Bella Rubin, the namesake astronomer, initiated this journey in the 1970s when observations of galaxy rotation disclosed that visible matter represented only a fraction of the universe. She discovered that stars on the galactic outskirts were moving faster than expected; according to Kepler’s Law, they should be traveling more slowly compared to stars nearer the galaxy’s center.
After extensive observations and calculations, it became evident that additional unseen mass must exist. This invisible entity is referred to as dark matter, and astronomers now estimate that it is nearly five times more abundant than visible matter, exerting gravitational effects that shape our observable universe.
“Visible entities are actually following the contours set by dark matter, not vice versa,” observes Stephanie Deppe at the observatory. Galaxies are believed to be arranged in what astronomers term the cosmic web, woven by filaments of dark matter that hold the visible stars through gravity. The images captured by Rubin provide an unprecedented view of this web.
Mapping this web also aids in uncovering the properties of dark matter. Is it composed of fast-moving, lightweight particles or is it cold and denser? “You can identify small anomalies, such as kinks in a stellar stream,” Deppe adds. These anomalies indicate where dark matter has accumulated along the filaments. Determining the mass will help to refine hypotheses regarding the type of dark matter present. Additionally, the structure of the cosmic web offers insights into dark energy, the force propelling the universe’s expansion.

Staff at the summit installing the Vera C. Rubin Observatory’s Commissioning Camera in August 2024.
Rubin Observatory/NSF/AURA/H. Stockebrand
The excitement surrounding precision astronomy is palpable at the observatory. During the evening’s observations, chatter fills the kitchen near the telescope control room. One of the telescope operators bounces with eagerness: “We hope the skies cooperate tonight,” a term used for opening the telescope’s shutter to capture images. “Indeed, we do,” his colleague responds, smiling over a cup of tea. As the sun sets, we collectively wish for a clear evening.
When the clouds part, the control room buzzes with activity. The operator skillfully adjusts the telescope to ensure proper focus. Every 30 seconds, a new image is captured, and an audio cue signals when the shutter opens and closes, followed by a satisfying whoosh as it resets. The telescope snaps a segment of the sky before dashing to the next location, creating a grid that will be stitched together.
All systems run smoothly until suddenly, a glitch arises. To optimize viewing opportunities, the observatory employs an automated system that determines where the telescope should aim, based on weather conditions and moon phases. However, this system has momentarily malfunctioned. Operators traverse the mountains for hours with scientists at base camp, diving into the code to locate the problem. Twenty minutes later, adjustments are made, and the regular shutter cadence resumes, with images flowing in once more.
“This is one of the best nights we’ve experienced. The data is exceptional,” notes Eli Rikov, Calibration Scientist. “I hope the processors can deliver high-quality scientific images.”
Once captured, the images embark on a swift journey around the globe. They traverse the 103,000 km stretch of fiber cables leading either across the Atlantic or Pacific, ultimately reaching the U.S. The images pass through a hub in Florida before arriving at the SLAC National Accelerator Laboratory in California.
Each image is approximately 32 gigapixels, comparable to a 4K movie, and arrives within about 10 seconds. William Omlan manages data on the observation deck. From there, the data is distributed to facilities in the UK and France, making the images accessible to scientists worldwide.
One of the most urgent analyses will focus on swiftly moving objects. The night sky constantly shifts and changes in unpredictable ways, and the Rubin Observatory is poised to catch these movements. It will track asteroids and comets moving across the sky, including those in the main asteroid belt between Mars and Jupiter, as well as Trans-Neptunian objects.
“Currently, we only know a few thousand objects,” explains an expert in the Kuiper Belt and other distant clouds. “Rubin could potentially increase our catalog tenfold.”
Moreover, it will help monitor potential threats from near-Earth objects, amplifying our known inventory from around 30,000 to approximately 100,000. The telescope has also successfully observed fast-moving interstellar visitors like Oumuamua, which zipped through our solar system in 2017, and Borisov, which arrived in 2019.
This census of solar system objects could also shed light on the elusive Planet 9, a hypothetical world—5 to 10 times Earth’s size—believed to exist in the outer solar system, inferred from the unusual orbits of Kuiper Belt objects. Simulations suggest it could be responsible, though conclusive evidence is still missing.
That may soon change. “Rubin might directly discover Planet 9, providing definitive proof or debunking its existence,” Deppe mentions.
One mystery the telescope won’t unravel is the uncertain future of American scientific funding. Jointly funded by the U.S. Department of Energy and the National Science Foundation (NSF), the latter has faced proposed budget cuts exceeding 50%. When I inquired about its implications, staff at the observatory were uncertain. “I won’t speculate about the potential impact of the President’s fiscal year 2026 budget request,” an NSF spokesperson responded.
But inside the control room, funding debates can wait. Though midnight approaches, shifts are far from over. Scientists work diligently until 3 or 4 a.m., but weariness seems absent. Every so often, someone exclaims, “Look at these stunning images!”
The first publicly released image appeared on June 23rd, capturing a full view of the southern sky every three nights. “The entire idea is to construct an observatory capable of collecting all the data demanded by the scientific community worldwide.”
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Source: www.newscientist.com