Sunday, January 18, 2009

Border-fence lights worry astronomers

Green Valley News and Sun
April 5, 2007

Astronomers in Southern Arizona and elsewhere in the Southwest have a new worry — possible light pollution from planned border fences and walls.

Boeing Co. is designing a 28-mile “virtual fence” near Sasabe on the border southwest of Green Valley.

Dan Brocious, spokesman for the Whipple Observatory on Mount Hopkins, said there has been talk of “stadium lights” in some border areas.

Astronomers are always concerned that man-made lights will diminish the night’s darkness when telescopes are trained upward.

“It’s not just here that more border lighting is a concern,” said Brocious.

He named several observatories that could be affected, including Kitt Peak on the Tohono O’odham Reservation, the new binocular telescope at Mount Graham, an Iowa State observatory at Elgin, the Guillermo Haro observatory at Cananea, Mexico, and others in Texas and California.

He said there is a lot of “glary, sidewise light” in the San Diego-Tijuana area.Brocious said astronomers have had good relations with the Border Patrol, but sometimes they request it to keep their lights pointed down, not sideways or up.

Besides the professional observatories there are several smaller, private observatories, including ones at Patagonia Lake and in the Sonoita area.

Brocious is frequently asked to talk about light pollution. When the new Wal-Mart Center was being developed he spoke against a proposal to exceed Pima County’s county’s lighting limits on the parking lot.

The International Dark-Sky Association is devoted to preserving the cloak of night-time darkness.Last September Boeing won a $67 million contract to build a high-tech virtual fence.

“What we are looking to build is a 21st century virtual fence” said Homeland Security Secretary Michael Chertoff.Other estimates on the cost of a 700-mile virtual fence run to $2 billion.The first phase, near Sasabe, will take three years to install.

Chertoff said because the topography along the border changes from place to place, “We don’t want to lock ourselves” into any one technology.Brocious said he hopes the virtual fence will rely on infrared light and other less-instrusive technology such as night scopes and sensors.

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