Megan Finnerty

The Republic | azcentral.com

A bill in the Arizona Senate would make it easier to know how much snacks cost at a gas station outside of Kingman, but harder to see the Milky Way.

House Bill 2507 would allow electronic billboards to start glowing in two counties in western Arizona where they are now banned.

The proposed areas of Mohave and La Paz counties are some of the darkest spaces left in America, which offer unparalleled views of celestial bodies for astronomical research.

These areas were declared off-limits to such signage in a 2012 deal that restricted electronic billboards to the Valley and areas along Interstates 10 and 8. Under the new measure, billboards still would not be allowed within 75 miles of key observatories around the state.

Astronomers say Arizona bill could hurt state's dark skies

The western Arizona darkness comes at a price for the cities of Kingman, Bullhead City and Lake Havasu City, said Rep. Sonny Borrelli, R-Lake Havasu City.

"We just want to make things fair economically. They (Maricopa County) get to do it, but Mohave County was excluded and it's just not fair," Borrelli said. "Advertisers would be able to buy space on these things, and cities could tax them."

He said he did not know how much of an economic impact new electronic billboards would have, and that any guess would be speculative.

Tim La Sota, who lobbies for billboard industry giant Lamar Advertising, the company that asked for the legislation, was also unable to say how much the new billboard spaces would be worth to his employer.

Astronomers, however, have calculated the value of dark skies: About $1.5 billion of capital investment as of 2016. Astronomy generates about $250 million annually in economic impact, said Jeffrey Hall, director of the Lowell Observatory in Flagstaff.

Hall, and others in the astronomy community, say the bill will damage Arizona's reputation as a destination for scientific research and will discourage investment and job growth in the state.

"We're sending a message that the dark-sky resource that Arizona has is something we’re willing to chip away at and possibly forego millions more in future investment," Hall said.

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Arizona is one of the darkest states in the nation, and is home to three of the country's largest telescopes: Lowell Observatory, Kitt Peak National Observatory southwest of Tucson, and Mount Graham International Observatory outside Safford.

Arizona is also one of the darkest places on the planet. Even with the Valley's vast sky glow, the state is home to more designated Dark Skies communities and parks than any other region, drawing scientists and visitors from around the world because its expanses of deep darkness are so rare in industrialized nations.

Under the legislation, the billboards would conform to existing standards. Graphics can't move, images must be static for at least eight seconds, the images must dim at night, and the signs musts go dark at 11 p.m. Municipalities retain the right to enact more restrictive legislation.

Arizona tries to maintain "dark skies" � do you notice?

Potential billboards would go up only along interstates and state highways, along Interstate 40, Interstate 15 and U.S. 93 around Kingman and Bullhead City, said La Sota.

While the glow from Las Vegas affects the night skies in these areas, they are still among the darkest regions of the country. Because brightness is relative, any increase in lighting would be noticeable, said Christian B. Luginbuhl, a founding member of the Dark Skies Coalition, who recently retired from the United States Naval Observatory in Flagstaff.

"I’m worried about the...people who just enjoy the night skies in their neighborhood," Luginbuhl said. "It really gets a lot brighter with even one billboard. It’s not just astronomy; it's about everyone being able to look up at the night sky and enjoy it."

Others caution that allowing electronic billboard expansion in one area of the state will invite other communities to do the same. Hall, of Lowell Observatory, said the bill is written so broadly that sign companies could make a case for opening up the rest of the state.