A smartphone with a 16-megapixel camera may seem cutting edge, but it won't impress astronomers now that the US Department of Energy's SLAC National Accelerator Laboratory has given the green light to start construction of the world's largest digital camera. With a resolution of 3.2-gigapixels (enough to need 1,500 high-definition television screens to display one image), the new camera is at the heart of the 8.4-meter (27.5-ft) Large Synoptic Survey Telescope (LSST) now under construction atop Cerro Pachón in Chile.
Not surprisingly, the new camera is no lightweight. The three-mirrored device is the size of a small car, tipping the scales at over 3 tons (2.7 tonnes). It's the result of a wide partnership of institutions that include Brookhaven National Laboratory, Lawrence Livermore National Laboratory, and SLAC, contains 189 sensors, has a resolution equivalent to 800,000 eight-megapixel cameras, and includes a filter-changing mechanism and shutter for viewing different wavelengths from the near-ultraviolet to the near-infrared.
Having passed Critical Decision 3, the last major approval decision, the camera will be built and tested over the next five years in a new 185-sq m (2,000-sq ft), two-story-tall clean room at SLAC in Menlo Park, California before being installed in the LSST.
In 2022, the camera and the LSST will begin a 10-year mission to take digital images of the entire Southern sky every few nights as part of a program to catalog the largest number of visible stars and galaxies yet, which is expected to generate about six million gigabytes of data per year. It's hoped that this will help astronomers to gain a better understanding of galaxy formations, aid in tracking potentially dangerous asteroids, and provide a better understanding of dark matter and dark energy, which is believed to make up 95 percent of the Universe.
"We’ve been working hard for years to get to this point,” said Nadine Kurita, camera project manager at SLAC. "Everyone is very excited to start building the camera and take a big step toward conducting a deep survey of the Southern night sky."
Source: SLAC
Probably because they know that the number of megapixels, or even gigapixels, is not a measure of image quality. That is why a 16 megapixel phone does not cost as much as the same DSLR, nor does it compare in image quality. Not all pixels are created equal. In comparison, medium format or large format film is capable of rendering gigapixel images if the quality of the lens, the photography, and the digital scanning is done right. I can create a 3.2 gigapixel image with only about ten shots using an off-the-shelf DSLR. I routinely combine as many as 100 images from my DSLR using a programmable Gigapan, which renders images more like 320 gigapixels, I prefer my DSLR. I can carry it. Probably the really critical factor for their sensor is light sensitivity, not pixels.
As for Carbons comments I wasn't aware that there are off the shelf DSLR cameras with 320 megapixel sensors. A 24Mpxl camera will need 134 shots to equate to 3.2Gpxl not just 10.
Photons arriving withing 1/4 wavelength of each other behave as if a single wavefront. Count up the pixels, crammed onto the sensor size. Does the spacing approach light wavelengths? Check out the lens aperture. You will see the reason we have astronomical telescopes with large objectives. Smartphone spatial resolution is poor, and much of the pixel area is dynamically re-addressed to give anti-shake stability compensation, pan ability, and "electronic zoom".