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PS1 Camera Installed

Electronics engineer Peter Onaka (left) and astronomer John Tonry assemble the Pan-STARRS gigapixel camera.
Photos by Richard Wainscoat

The world's largest and most advanced digital camera has been installed on the Pan-STARRS-1 (PS1) telescope on Haleakala, Maui. Built at IfA Manoa, the gigapixel camera will capture images that will be used to scan the skies for killer asteroids, and to create the most comprehensive catalog of stars and galaxies ever produced.

"This is a truly giant instrument," explained astronomer John Tonry, who led the team that developed the new camera. "It allows us to measure the brightness of the sky in 1.4 billion places simultaneously. We get an image that is 38,000 by 38,000 pixels in size, or about 200 times larger than you get in a high-end consumer digital camera. It's also extremely sensitive: in a typical observation we will be able to detect stars that are 10 million times fainter than can be seen with the naked human eye."

The camera is a key component of the Pan-STARRS project, which is designed to search the sky for objects that move or vary. When fully operational, each patch of sky visible from Hawaii will be photographed automatically at least once a week. Powerful computers at the Maui High Performance Computer Center will scrutinize each image for the minuscule changes that could signal a previously undiscovered asteroid. Other computers will combine the data from several images, calculate the orbit of the asteroid, and send warning messages if the asteroid has any chance of colliding with Earth during the next century.

Gigapixel camera focal plalne

John Tonry holds the focal plane with 60 silicon chips.

The silicon chips at the heart of the camera were developed in collaboration with Lincoln Laboratory of the Massachusetts Institute of Technology. They contain advanced circuitry that enables instantaneous corrections for any image shake caused by Earth’s turbulent atmosphere. The image area, which is about 16 inches (40 cm) across, contains 60 identical silicon chips, each of which contains 64 independent imaging circuits. Splitting the image area into about 4,000 separate regions in this way has three advantages: data can be recorded more quickly, "dazzling" of the image by a very bright star is confined to a small region, and any defects in the chips affect only a small part of the image area.

So much data will be produced by the camera that the team in Manoa has had to develop novel ways to handle the deluge. Electronics engineer Peter Onaka led the team that designed an ultrafast 480-channel control system, while a group led by astronomer Eugene Magnier developed the software that is able to analyze the thousands of gigabytes of data that the camera will produce each night.

Online PS1 camera information:
http://pan-starrs.ifa.hawaii.edu/public/
http://pan-starrs.ifa.hawaii.edu/public/design-features/cameras.html

Streaming Flash video:
http://www.ifa.hawaii.edu/info/press-releases/GPC/GPCflash.html