Texas’ oil and gas regulator on Wednesday asked companies to reduce their light pollution near the McDonald Observatory in West Texas, one of the world’s largest telescopes.

It’s the first time the Texas Railroad Commission has addressed the issue of “sky glow” from drilling rigs, gas flares and well completion operations in the Permian Basin, the state’s largest oil field. State laws, which went into effect in 2011, tried to address sky glow that could threaten the observatory’s research work, but few oil and gas companies knew about the rules or the potential conflict between industry and science.

The McDonald Observatory was established in 1932 north of Fort Davis, still a remote part of the state, and is run by the University of Texas at Austin. Its Hobby-Eberly Telescope atop Mount Fowlkes is the largest in North America. There are two other research telescopes atop nearby Mount Locke.

Pioneer Energy, a San Antonio-based contract driller and oil field services company, and McDonald Observatory have worked together to study the sky glow problem, testing lighting on drilling rigs that is still safe but doesn’t send light skyward like a beacon.

Pioneer Energy CEO Stacy Locke and Bill Wren, a special assistant to the superintendent at the McDonald Observatory, authored a paper on the topic for the Society of Petroleum Engineers, which was presented at the group’s conference in Denver last March.

The Railroad Commission’s new notice asks operators to be aware of the rules, links to Locke and Wren’s research and asks companies to be aware of the problem.

“You are encouraged to consult these resources and consider ways to reduce stray light. The solutions can be simple and cost effective and can actually improve nighttime visibility and increase worker safety,” the notice said.

You can see the notice to operators here and read about the history of the issue here.

The Texas Legislature passed a bill in 2011 requiring communities within 57 miles of the McDonald Observatory to regulate outdoor lighting. The law requires permits for the installation of new outdoor lights — though it grandfathers existing lights — and makes violations a Class C misdemeanor.

The territory covers seven counties — Jeff Davis, Hudspeth, Culberson, Reeves, Pecos, Presidio and Brewster — and 28,000 square miles. Wren has called it the largest dark sky reserve in the world.

Although the oil and gas industry has been receptive to the idea of maintaining a dark sky near the observatory, the big hurdle was that few people had known about the problem, and the Railroad Commission has no rules of its own regarding light fixtures.