Staff members give the media a tour of the newly built 3,200 megapixel LSST camera, the largest camera ever built, at the SLAC National Accelerator Laboratory in Menlo Park, California, on Thursday, April 11, 2024. After twenty years of work, the device will soon be packed up and shipped to a mountaintop in Chile to help researchers better understand dark matter, dark energy and other mysteries of the universe. (Jane Tyska/Bay Area News Group)
The world’s largest camera was on its way from its birthplace at the SLAC National Accelerator Laboratory in Menlo Park to a mountaintop half a hemisphere away in the foothills of the Andes. But there was a problem. And it took an order from Chilean President Gabriel Boric to solve this problem.
“This was a very high-stakes operation. It is the future of American astronomy,” said SLAC engineer and camera project manager Travis Lange. “There are literally thousands of people who plan to use the data.”
In addition to the famous linear accelerator used to find the smallest particles in the universe, and now the enormous camera, SLAC is known for building large, sophisticated machines that use X-rays, lasers and electron beams to unravel riddles on Earth and in the cosmos.
Most of the monumental journey had gone smoothly for the $168 million instrument, which will deliver never-before-seen vistas into space and enable groundbreaking astronomical research from its perch at the purpose-built Rubin Observatory atop the Cerro Pachón ridge in Chili.
The slow, pre-dawn journey began May 14 in a shipping container on a flatbed truck that pulled off SLAC Highway 280 and then headed to San Francisco International Airport. Within hours, the container containing the 5-foot-tall, 10-foot-long, 6,250-pound camera was safely secured to the floor of a chartered 747 cargo plane, along with two additional containers and dozens of crates of associated equipment.
The nearly 11-hour flight to Santiago, Chile, also went well, said Lange and fellow SLAC engineer Margaux Lopez, who was tasked with leading the operation to pack the device and ship it to the observatory.
But they had no intention of attacking truck drivers blocking highways around Santiago, the country’s capital, during protests that threatened to throw a giant logistical wrench into the transportation mission.
It is a testament to the camera’s importance to science that Chilean Interior Minister Carolina Tohá Morales took the call about the blockade from an official of the Association of Universities for Research in Astronomy, then called Boric, who ordered a police escort so the camera could get through.
There were a few hiccups as the nine-truck camera convoy made its way for more than six hours along a 22-mile dirt road to Cerro Pachón at about 8,000 feet in the foothills of the Andes — most notably a loss of traction by the vehicle that the camera container – but it arrived safely mid-day on May 16.
Lopez, who has been working on the transportation plan since 2018, expressed “very relieved” and “also proud” on Tuesday. Once she heard about the strike and a separate labor action involving equipment handlers at Santiago airport, she created five different scenarios to address the issues.
“Although there were some hiccups, we were able to resolve all the events,” Lopez said via video from the observatory in Chile. “It happened largely according to plan, and that’s pretty impressive.”
Sending the enormously expensive and important Legacy Survey of Space and Time camera, with its 189 delicate light sensors, five delicate filters and various complex electronics by road, air and then road, put a heavy strain on Lopez and Long.
“It’s kind of like sending your kid to college,” Lange said. “It’s amazing and terrifying at the same time.”
At the Rubin Observatory, the camera will likely be bolted to the end of a huge telescope in October or November, Lange said. Once installation and configuration are complete, images of 20 billion galaxies will be stitched together in expansive panoramas, giving astronomers ever-changing views of colliding and exploding stars, asteroids and mysterious interstellar phenomena, including dark energy and dark matter.
Given the value of the instrument and its importance to science, SLAC had kept the transport mission shrouded in secrecy and declined to specify when the camera would depart for San Francisco airport.
“I like to think there are no bad actors who would sabotage something like this, but it’s not hard for us not to advertise that it’s going out,” Lange said previously.
Building the camera required a facility with air that was 1,000 times cleaner than an average indoor space, to prevent dust and other materials from getting onto the highly sensitive outer lens and degrading its quality, or into the internal workings of the camera. device.
Engineers custom-built an enclosed, clean room with a 23-foot ceiling, and everyone who entered had to don head-to-toe white bunny suits and blue latex gloves, giving the day’s activities the feel of a crime scene.
Before shipment, the device was packaged in a giant silver plastic bag and looked like a burrito, Lopez said. Because moisture is an enemy of the instrument, dozens of sachets of moisture-absorbing desiccant went into the bag, each the size of a small pillow and weighing several pounds—industrial versions of the small packets that come with many consumer electronics products.
The camera was bolted to a 4,000-pound yellow steel frame and then lifted and lowered into a pristine steel shipping container, where the frame was fitted with sensors to measure and track the impact on the camera from bumps and shocks – data from after the trip showed were minimal.
Lange’s main concerns before shipping were the camera’s 189 custom silicon sensors, which were spaced a few hairs wide and cost $150,000 each.
“It doesn’t take much movement to cover that distance,” Lange said earlier. “When they make contact, they break. It would be pretty bad.”
Previously, to ensure that the transport device could keep the camera safe during its journey to Chile, a dummy version of the device, heavily weighted with black iron gym plates and connected to impact sensors, was placed on a truck and driven around. Bay area.
“We sent the driver on an eight-hour drive and said, ‘Find the worst roads you can find. Hit 101. Hit 880,” Lange said. “During that process we recorded the shocks.”
Then they did a much longer test drive: by truck to Miami, then by plane to Chile and to the observatory site and back to Menlo Park.
Now the camera waits in its new cleanroom on the third level of the eight-story observatory. On the day of installation, the instrument will travel in a giant five-level elevator to the facility’s dome, and technicians will use 108 large, high-strength bolts to secure it to the tip of the telescope.
Five months of testing follow. If all goes well, the first photons of light will enter the camera in the spring.
The camera and the telescope, Lange said, “are going to revolutionize astronomy.”