Vera Rubin Observatory Aims to Revolutionize Astronomy

The atmosphere above Celopachen, a mountain in Chile standing over 2600 meters high, is sparse. Taking a trip up the stairs inside the dome of the Vera C. Rubin Observatory requires a breath. It’s cool, serene, immensely spacious—and then the entire dome rotates, revealing the sky.

As night envelops the landscape, the stars multiply, more abundant than I’ve ever witnessed. The Milky Way glows vibrantly, and I spot the small Magellanic Cloud, one of our galaxy’s companions. The Rubin telescope, however, dominates the scene—it’s massive, boasting the world’s largest digital cameras and lenses, with a weight of 350 tonnes. This reflective telescope gathers light through its mirror, with the largest mirror measuring 8.4 meters in diameter, designed to fit snugly through the 8.5-meter wide tunnel leading to the summit.

Despite its impressive heft, the telescope is swift, poised to transform our understanding of our solar system, galaxies, and the universe. Every three nights, it captures a survey of the Southern Sky. While previous sky investigations took weeks or months, Rubin accomplishes this in just half the time, providing a sort of cosmic time-lapse.

“By photographing the sky every three days, we can layer those images to delve deeper,” explains scientist Kevin Rail. “Thus, a decade from now, you’ll delve into the universe’s inner workings and its structure,” he adds.

Unraveling that structure is among the observatory’s goals, focusing on how dark matter distorts the universe. Bella Rubin, the namesake astronomer, pioneered this quest in the 1970s through galaxy rotation observations that indicated visible matter was but a fraction of what exists. She noted that stars at a galaxy’s edge were zipping by too quickly, contradicting Kepler’s Law, which suggested they should move at slower velocities compared to those near the galactic center.

After extensive observation and calculations, the conclusion was clear: an unseen entity must be present—this is now known as dark matter. Astronomers believe it comprises nearly five times more mass than visible matter, and its gravitational pull shapes the universe we observe.

“Visible matter actually traces dark matter’s gravitational field, not the other way around,” says Stephanie Deppe at the observatory. Galaxies are perceived to exist in what astronomers term the cosmic web, interlinked by dark matter filaments that capture the stars we can observe. Rubin’s images offer unparalleled views of this web.

This mapping effort aids in deciphering dark matter’s nature—whether it’s composed of hot, light, fast-moving particles or colder, aggregated ones. “We seek small disturbances, like kinks in stellar streams,” Deppe explains. These disturbances indicate sections where dark matter is concentrated within filaments. Understanding the mass from these observations refines our knowledge of dark matter’s characteristics. Moreover, deciphering the cosmic web’s structure can enhance our comprehension of dark energy, the force accelerating the universe’s expansion.

The enthusiasm for precision astronomy is palpable at the observatory. During my observation night, excitement buzzes through the air, particularly in the kitchen adjoining the control room. One of the operators, practically bouncing with energy, exclaims, “We hope the sky is clear tonight!” This term refers to opening the telescope shutter for imaging. “Indeed, we do,” replies a colleague, grinning over their tea. As twilight descends, we all hope for a cloudless sky.

When the clouds part, the control room buzzes with energy. An operator continues fine-tuning the telescope for optimum image focus. Every 30 seconds brings a new image, followed by the sound of the shutter opening and closing—like a hushed reverberation through the dome as it swiftly captures and moves on to the next section of the sky, constructing an intricate cosmic puzzle.

Suddenly, an unexpected glitch occurs. To maximize observational efficiency, the observatory employs an automated program that directs the telescope based on weather and moon phases, but this system stumbles momentarily. Operators venture through the rugged terrain alongside scientists at base camp, collaborating to troubleshoot the issue. After about 20 minutes, adjustments are made, and normal operations resume, with the rhythm of the shutter beginning anew.

“This is one of our best nights; everything is flowing smoothly—this data is excellent,” reveals Eli Rikov, the calibration scientist. “I’m optimistic the processors will produce high-quality scientific images.”

Once captured, images embark on a rapid journey around the globe. They traverse down the mountain on an extensive network of 103,000 km of fiber optic cables, reaching the Atlantic or Pacific Oceans before arriving in the US. Images pass through a central hub in Florida before arriving at the SLAC National Accelerator Laboratory in California.

Each captured image consists of about 32 gigapixels, roughly the equivalent of a 4K movie, and they arrive in approximately 10 seconds. William Omlan, overseeing data on the observation deck, then disseminates this data to facilities in the UK and France, ensuring it reaches scientists worldwide.

Most urgent analyses focus on rapidly moving celestial bodies. The night sky is in constant flux, exhibiting blips and changes in unpredictable patterns. The Rubin Observatory is uniquely equipped to capture these dynamic movements, allowing for near-real-time detection of rapidly changing objects. The telescope tracks asteroids and comets racing across the night sky, including those within the asteroid belt between Mars and Jupiter, as well as trans-Neptunian objects.

“Currently, we are aware of thousands of these objects,” says the Kuiper Belt and Oort Cloud researcher. “Rubin will likely increase that count tenfold.”

The observatory also plays a crucial role in monitoring potential threats from near-Earth objects, aiming to expand our knowledge from about 30,000 to an estimated 100,000. It has even succeeded in capturing fast-moving interstellar objects, such as Oumuamua, which passed through our solar system in 2017, and Borisov, which followed in 2019.

This extensive census of the solar system might also solve the enigma of Planet 9. Intriguing evidence suggests a body—5 to 10 times the mass of Earth—exists in the outer solar system, inferred from Kuiper Belt objects exhibiting peculiar yet similar orbits. Simulations propose that such a planet could be influencing these orbits, though direct evidence remains elusive.

That may soon change. “Rubin’s data will either uncover definitive evidence of Planet 9 or eliminate any existing doubts,” predicts Deppe.

However, there’s also uncertainty looming over American science funding. The observatory receives joint funding from the US Department of Energy and the National Science Foundation (NSF), the latter having faced draconian budget cuts proposed by over half. When I inquired about the potential implications, staff members seemed nonplussed. “I prefer not to speculate on the effects of the President’s budget request for fiscal year 2026,” an NSF spokesperson told me later.

For now, though, back in the control room, financial concerns take a backseat. Approaching midnight, the shift continues. Scientists work diligently until 3 am or 4 am, yet fatigue seems nonexistent. Occasionally, someone brightens the room with, “Look at these stunning images!”

The first published image emerged on June 23rd, showcasing a complete view of the southern sky obtained every three nights. “The vision is to create an observatory that can capture all the data the world wishes for.”