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In this issue:
A Camera's Odyssey
Word of the Week: Pi
Happy Thanksgiving!

SLAC Today

Wednesday - November 24, 2010

A Camera's Odyssey

(Photo - camera)
Part of the fixture wrapped in protective plastic and crated ready for loading into the shipping container. (Photo: Reidar Hahn, Fermilab.)

In comparison to scouring the universe for elusive dark energy, transporting a fragile, multi-ton, one-of-a-kind camera from the windswept Illinois prairie to the barren mountaintop of Cerro Tololo in the Chilean Andes is a simple feat. By any other comparison, though, it’s a massive undertaking.

The Dark Energy Survey collaboration, which SLAC joined in 2009, has worked at Fermilab since 2004 to construct a large 570-megapixel camera that will take snapshots of the night sky to search for dark energy. Scientists believe dark energy is causing the expansion of the universe to speed up. Parts of the Dark Energy Camera are already fully operational, and the DES collaborators are beginning to ship them one by one to Cerro Tololo Inter-American Observatory in Chile through the rest of the year. There, scientists will attach the camera to an existing telescope.

Many of the camera’s components have already traveled to Fermilab from far-off lands, including England, Germany, Spain and Italy, but they have even farther to go. The first piece of DECam recently arrived at Cerro Tololo after a long, complicated journey over land and sea. 

Read more in Symmetry Breaking...

Word of the Week: Pi

Pi is a mathematical constant equal to the circumference of a circle divided by its diameter, or the area of a circle divided by the square of its radius. It is represented by the Greek letter, π.

The value of pi is often approximated as 3.14159265, although some have calculated as many as five trillion digits after the decimal point—a series that neither ends nor repeats itself.

Pi has also found a place in pop culture. Many celebrate "Pi Day" on March 14 (twice, at 1:59 a.m. and p.m., if you want to get specific). The day often includes making or eating pie. Fittingly, pies are round and have the necessary parameters to calculate pi.

(Image - cornucopia)

Happy Thanksgiving!

(Image - turkey)


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