Astrophysics has a new instrument of unprecedented reach. Atop Cerro Pachón, roughly 300 kilometres north of Santiago, the Vera C. Rubin Observatory — home of the 8.4-metre Simonyi Survey Telescope — has begun regular operations for the Legacy Survey of Space and Time (LSST). For the next decade, the telescope will sweep across the southern hemisphere, revisiting the same fields of sky again and again, until a single, continuously updating "movie" of the cosmos emerges.
The world's largest digital camera
The heart of the system is the LSST Camera, a 3.2-gigapixel detector the size of a car hood and made up of 189 individual sensor chips bolted into an aluminum frame. A single full-frame image would fill 400 4K television screens laid side by side. Rather than staring at one star field for hours, Rubin instead takes wide, fast snapshots — roughly 30 seconds each — so it can cover enormous swathes of sky before the Earth rotates them out of view.
A real-time discovery machine
Because the survey looks at the same patch of sky repeatedly, it is uniquely sensitive to anything that changes. A supernova that flickers on in a distant galaxy. A near-Earth asteroid creeping closer to our planet. A quasar brightening as gas falls into a black hole. Each night the pipeline produces an estimated seven million alert images that flag transient events, feeding a stream of real-time discoveries to astronomers worldwide. Rubin is expected to catalogue millions of new asteroids within its first two years alone and to detect interstellar objects passing through the Solar System.
Probing the invisible universe
The long-term scientific payoff goes beyond spotting moving rocks. By watching billions of galaxies over ten years, LSST will chart how the universe's expansion has accelerated over time — the central puzzle left by dark energy, which makes up about 70 percent of the cosmos but has never been directly detected. Gravitational lensing, the bending of light by hidden mass, will let the survey map dark matter across vast volumes of space with a precision no ground-based instrument has matched.
Knowledge takeaway: The Vera C. Rubin Observatory began full LSST operations in late June 2026 from Cerro Pachón, Chile; its 8.4-metre telescope pairs with a 3.2-gigapixel LSST Camera — the largest digital camera ever built; the decade-long survey revisits the southern sky every few nights, producing roughly 7 million change alerts per night; LSST will test whether dark energy evolves over time and map dark matter across the cosmos; in its first two years it is expected to discover millions of new asteroids and sensitive interstellar objects.