The world largest digital camera has completed its first test successfully by capturing the first 3,200-megapixel images of a Broccoli. This camera is meant to be part of the telescope at the Vera Rubin Observatory where they will be taking photographs of the sky to help us improve our understanding of the universe. Once it goes live it will photograph its entire field of view (the area of about 40 full moons) every few nights, which will give the researchers the ability to pinpoint the locations of billions of stars and galaxies, while also catching anything that moves or flashes.
The imaging sensors for the camera took over 6 months to assemble as they need to be mounted very precisely. The sensors are assembled in a grid of 9 sensors called a scientific raft and the whole setup consists of 25 rafts. Each raft is precisely mounted with a gap of just 5 human hairs between each raft. Each raft costs approximately $3 million each so you won’t be able to buy it from the corner shop anytime soon. Once the sensors were assembled successfully the whole apparatus is cooled to a negative 150 degrees Fahrenheit which is their operating temperature.
Even though the assembly was completed back in January the scientists were unable to take test pictures due to the Coronavirus pandemic till May. Even though the sensor assembly has been completed the team still doesn’t have all the remaining camera components such as lenses. So they had to improvise by using a 150-micron pinhole to project images on to the CCD array. That’s correct, they used the same ‘technology’ as what we used as kids to learn about photography to take a picture with the largest ever camera built.
Since they needed to take a picture of something that would allow them to verify the quality of the picture they decided to take a picture of Broccoli which has a lot of lumps & bumps on its surface making its structure perfect to test out the new camera sensors.
“Taking these images is a major accomplishment,” said Aaron Roodman, professor and chair of the particle physics and astrophysics department and the scientist at SLAC responsible for the assembly and testing of the LSST camera, in a statement.
“With the tight specifications we really pushed the limits of what’s possible to take advantage of every square millimeter of the focal plane and maximize the science we can do with it.”
The team is estimating that the camera would be ready for testing by mid-2021 before it’s sent off to Chile for installation in the Vera Rubin Observatory.
Source: Vera Rubin: Super telescope’s giant camera spies broccoli
– Suramya