By Satyen Mohapatra
By Satyen Mohapatra
Astronomers and scientists are waiting with bated breath to witness the first images of the universe captured by the world’s largest digital camera, which cost $168 million. The images are expected to be released on June 23, 2025.
It has taken nearly 20 years to build and install this massive camera on a telescope at the Vera C. Rubin Observatory in Chile. The sharpness and accuracy of the images are expected to be unprecedented, thanks to the camera’s staggering 3.2 billion-pixel resolution. Each image will be so detailed that it could capture a golf ball from a distance of 15 miles.
The digital camera uses Charge-Coupled Devices (CCDs), which are highly sensitive photon detectors used in telescopes instead of traditional film or photographic plates—similar to those in digital cameras. A CCD is a tiny microchip onto which the light collected by the telescope is focused. This microchip consists of a large grid of individual light-sensing elements called pixels. Each pixel is extremely small, about 10 micrometers squared, printed onto a piece of silicon.
With this high-resolution camera, scientists hope to shed more light on the elusive dark matter and dark energy—two invisible forces believed to influence the structure and behavior of the universe. The Vera C. Rubin Observatory is named after the astronomer who first provided compelling evidence for the existence of dark matter.
The camera’s lens itself is 1.57 meters wide, making it the largest lens ever constructed. The camera, known as the Legacy Survey of Space and Time (LSST) camera, contains nearly 190 ultra-sensitive CCD sensors that are cooled to minus 100 degrees Celsius to reduce electronic noise.
The camera will take photographs while the telescope scans the southern hemisphere’s sky. The level of detail and clarity in these images is expected to be unlike anything seen before. The camera was built at the SLAC National Accelerator Laboratory in California.
The project is funded by the U.S. National Science Foundation, the Department of Energy, and several private philanthropists. The camera’s sensors alone weigh over 2,720 kilograms. Every image captured by the LSST camera will contain over 3 billion pixels.
The telescope will scan the sky repeatedly, compiling a dynamic, evolving map of the cosmos. It is expected to catalogue more than 20 billion galaxies, track near-Earth asteroids that may pose threats, and observe exploding stars (supernovae).
The LSST camera does not work alone—it is paired with a sophisticated system of mirrors, including a primary mirror that measures 8.4 meters across. While optical telescopes and cameras both use lenses to focus light, telescopes are designed to magnify distant objects, whereas cameras are used to digitally capture and record what the telescope sees.
The LSST camera will collect approximately 20 terabytes of data every night—hundreds of times more than most existing telescopes. Over a year, the data it gathers is expected to surpass the cumulative data collected by all previous telescopes.
India’s Largest Optical Telescope
India’s largest optical telescope is the 3.6-meter Devasthal Optical Telescope, located in the Nainital district of Uttarakhand. It is designed to study celestial objects at optical wavelengths and is a national facility.
Commissioned in 2016 by the Aryabhatta Research Institute of Observational Sciences (ARIES), the telescope is equipped with instruments that provide both spectral and imaging capabilities in the visible and near-infrared bands.