April 13, 2024

SLAC completes construction of the largest digital camera ever built for astronomy

This article has been reviewed in accordance with Science X’s editorial process and policies. The editors have highlighted the following attributes, ensuring the credibility of the content:

checked

trusted source

review


A front view of the complete LSST camera, showing the 3,200-megapixel focal plane inside it. Credit: Jacqueline Ramseyer Orrell/SLAC National Accelerator Laboratory

× to close


A front view of the complete LSST camera, showing the 3,200-megapixel focal plane inside it. Credit: Jacqueline Ramseyer Orrell/SLAC National Accelerator Laboratory

After two decades of work, scientists and engineers at the Department of Energy’s SLAC National Accelerator Laboratory and their collaborators are celebrating the completion of the Legacy Survey of Space and Time (LSST) Camera.

As the heart of the Vera C. Rubin Observatory, the 3,200-megapixel camera will help researchers observe our Universe in unprecedented detail. Over 10 years, it will generate a huge trove of data about the southern night sky, which researchers will mine for new information about the universe.

This data will help in the quest to understand dark energy, which is driving the accelerating expansion of the universe, and in the search for dark matter, the mysterious substance that makes up about 85% of the matter in the universe. Researchers also have plans to use Rubin’s data to better understand changes in the night sky, the Milky Way and our own solar system.

“With the completion of the unique LSST camera at SLAC and its imminent integration with the rest of the systems at the Rubin Observatory in Chile, we will soon begin producing the largest film ever and the most informative night sky map ever assembled,” said Director of Rubin Observatory Construction and professor at the University of Washington, Željko Ivezić.

To achieve this goal, the SLAC team and its partners built the largest digital camera ever built for astronomy. The camera is about the size of a small car and weighs around 3,000 kg (3 metric tons), and its front lens is more than 1.5 meters in diameter – the largest lens ever made for this purpose.

Another 3-foot-wide lens had to be specially designed to maintain shape and optical clarity while also sealing the vacuum chamber that houses the camera’s massive focal plane. This focal plane is made up of 201 individual custom CCD sensors and is so flat that it varies by no more than one-tenth the width of a human hair. The pixels themselves are just 10 microns wide.

Still, the camera’s most important feature is its resolution, which is so high that it would take hundreds of ultra-high-definition TVs to display just one of its full-size images, said Aaron, a SLAC professor and deputy director of the Rubin Observatory and camera program leader. Roodman.

“Their images are so detailed they could bounce a golf ball from about 15 miles away, while covering a swath of the sky seven times the size of the full moon. These images of billions of stars and galaxies will help unlock the secrets of the universe .”


The camera will be atop the Rubin Observatory’s Simonyi Research Telescope, high in the Chilean Andes. Credit: Rubin Observatory/National Science Foundation/AURA

× to close


The camera will be atop the Rubin Observatory’s Simonyi Research Telescope, high in the Chilean Andes. Credit: Rubin Observatory/National Science Foundation/AURA

Searching for dark matter and dark energy

Now that the LSST camera is complete and has been extensively tested at SLAC, it will be packed and shipped to Chile and taken to Cerro Pachón, 8,900 feet high in the Andes, where it will be hoisted atop the Simonyi Research Telescope later. in this year. year.

Once up and running, the camera’s essential purpose is to map the positions and measure the brightness of a large number of objects in the night sky. From this catalog, researchers can infer a wealth of information.

Perhaps most notably, the LSST camera will look for signs of weak gravitational lensing, in which massive galaxies subtly bend the paths that light from background galaxies takes to reach us. Weak lenses reveal something about the distribution of mass in the universe and how it has changed over time, which will help cosmologists understand how dark energy is driving the expansion of the universe.

The observatory is the first built to study faint lenses on this scale, and the project has led scientists and engineers to develop a range of new technologies, including new types of CCD sensors and some of the largest lenses ever made – and ensure that all of these components work. well together, said Martin Nordby, SLAC senior engineer and LSST camera project manager.

Scientists also want to study patterns in the distribution of galaxies and how they have changed over time, identifying clusters of dark matter and detecting supernovae, which can help to better understand both dark matter and dark energy.

Risa Wechsler, a cosmologist who directs the Kavli Institute for Particle Astrophysics and Cosmology at SLAC and Stanford University, said it was an extraordinary moment. “There are so many scientists here at SLAC and around the world who will find something valuable in the data this camera will produce,” said Wechsler. “This is an exciting time to study cosmology.”


An artist’s rendering of the LSST camera showing its main components, including lenses, sensor array, and trunk. Credit: Chris Smith/SLAC National Accelerator Laboratory

× to close


An artist’s rendering of the LSST camera showing its main components, including lenses, sensor array, and trunk. Credit: Chris Smith/SLAC National Accelerator Laboratory

What else do you do with a camera that big?

The same images that reveal details of distant galaxies will help researchers study something closer to home: our own galaxy, the Milky Way. Many of its stars are small and faint, but with the sensitivity of the LSST camera, researchers hope to produce a much more detailed map of our galaxy, providing information about its structure and evolution, as well as the nature of the stars and other objects within. her.

Even closer to home, researchers hope to create a much more complete census of the many small objects in our solar system. According to estimates from the Rubin Observatory, the project could increase the number of known objects by a factor of 10, which could lead to a new understanding of how our solar system formed and perhaps help identify threats from approaching asteroids. rest of the planet. .

Finally, Rubin scientists will observe how the night sky is changing – for example, how stars die or how matter falls into supermassive black holes at the centers of galaxies.

A team effort

SLAC Director John Sarrao said the camera is a “tremendous achievement” for the lab and its partners. “The LSST Chamber and Rubin Observatory will open new windows into our universe, yielding deep insights into some of its greatest mysteries while revealing wonders closer to home,” said Sarrao. “It’s exciting to see SLAC’s scientific and technical expertise, project leadership, and strong global partnerships come together in such an impactful way. We can’t wait to see what comes next.”

Among the partner laboratories that contributed knowledge and technology are Brookhaven National Laboratory, which built the camera’s digital sensor array; the Lawrence Livermore National Laboratory, which with its industrial partners designed and built lenses for the camera; and the National Institute of Nuclear and Particle Physics at the National Center for Scientific Research (IN2P3/CNRS) in France, which contributed to the design of the sensor and electronics and built the camera’s filter switching system, which will allow the camera locate six separate devices light bands from ultraviolet to infrared.


Credit: SLAC National Accelerator Laboratory

Paul O’Connor, senior physicist in Brookhaven’s Instrumentation Division, said, “The Brookhaven Lab team, some of whom have worked on the project for more than 20 years, are excited to see the completion of the LSST camera. Our fast, CCD modules Ultrasensitive sensors, which we developed with several collaborators, will contribute to the groundbreaking science provided by the Rubin Observatory over the next decade, and we look forward to collaborating on this flagship astronomical research.”

A key feature of the camera’s optical assemblies are its three lenses, one of which at 1.57 meters (5.1 feet) in diameter is considered the largest high-performance optical lens ever manufactured in the world. “Lawrence Livermore National Laboratory is extremely proud to have had the opportunity to design and oversee the manufacturing of large optical lenses and filters for the LSST camera, including the largest lens in the world,” said Vincent Riot, LLNL engineer and former director of LSST camera project manager.

“LLNL has been able to leverage its expertise in large optics, built over decades of developing the world’s largest laser systems, and is excited to see this unprecedented instrument completed and ready to make its journey to the Rubin Observatory.”

IN2P3/CNRS camera scientist Pierre Antilogus said: “To make a 3D movie of the universe, the camera had to take an image in about 2 seconds and change filters in less than 90 seconds. That’s quite a feat for a camera this size. And if the focal plane size of the LSST Camera is unique, the density of the technology inside is even more impressive. By being responsible for the filter changing system and contributing to the focal plane, our team is very pleased to have to have participated in this collective adventure to develop such a powerful camera.”

Building the camera was also a rewarding challenge for the SLAC team who built it and led the project, said Travis Lange, deputy camera project manager and camera integration manager. “I’m really proud of what we built,” he said. “This was such a unique project that exposed me to incredible experiences – who would have imagined that the Secretary of State and Speaker of the House would hold a press conference in front of the chambers’ clean room? follow.”

Leave a Reply

Your email address will not be published. Required fields are marked *