The 1.4-Gigapixel Camera Standing Between Us and Armageddon

Originally posted at gizmodo.com

Andrew Tarantola 

— First step in preventing Armageddon: Spot the asteroid before it obliterates all life on earth. The PS1 Telescope sits atop a Hawaiian mountain with a 1.4-gigapixel digital camera to ensure we get the Ben Affleck-approved ending, not Deep Impact.

The PS1 telescope is the first of four Pan-STARRS (Panoramic Survey Telescope & Rapid Response System), a series of telescopes designed to discover, track, and map near-Earth asteroids ranging in size from 300 meters (984 feet, or "Say goodbye to Dallas-Fort Worth and all of its surrounding suburbs") to 1-kilometer (0.6-miles, or "Congratulations, you get to witness the end of the world"). All four telescopes will be located either at Mauna Kea or Haleakala on Maui and will point in the same direction, so that CCD artifacts caused by chip defects and cosmic rays can be removed. The four images are then combined to create an image equivalent to that from a 3.6m telescope— allowing it to see objects ten times fainter than other surveys. The entirety of the Hawaiian night sky will be observed 3 times each lunar cycle.

Twice a minute, the PS1 captures a 1,400-megapixel (1.4 gigapixels) image of a specific region in the night sky. That's 3,600 times bigger than the Hubble's main camera with a resolution 1,000 better than the Red One. If you printed that image at 300dpi, it'd cover half a basketball court. In all, it generates 5TB of data every night and maps the entirety of the sky every six months. "It provides the best early-warning system we have," according to Edo Berger, a professor with the Harvard-Smithsonian Center for Astrophysics.

The camera itself is 40cm square and packed with about 1.4 billion pixels. Individual CCD (charge-coupled device) cells are grouped in 8x8 squares on a single 5cm square silicon chip, called an orthogonal transfer array (OTA). There are a total of 60 OTAs in the focal plane of each telescope. The system is designed like this so that if one CCD cell or even a whole OTA fails, it alone can be swapped out instead of having to replace the entire array.

And it's not just dangerous space rocks the PS1 is finding. "We have been able to find more explosive astronomical phenomena (like supernova explosions) in one month than the entire astronomical community found in a whole year," Berger said, "We will also be able to map the solar system in much greater detail than was previously possible and to study the formation of the Milky Way galaxy through observation at an unprecedented sensitivity."

So thank you PS1 for giving us the heads up about killer asteroids and exploding stars... though if it gets me out of seeing another Tea Leoni movie, the end of the world doesn't sound too bad.