A NASA scientific research balloon flew 25 miles above Durango and the Cortez area on Wednesday, craning locals’ necks and prompting a swarm of speculation.

The balloon, which is larger than a football field, took off from Fort Sumner, N.M., at noon Tuesday and was scheduled to land just before sunset Wednesday.

Scientists from Harvard University are using it to study X-ray sources from black holes and quasars, said Keith Koehler, a public information officer at NASA’s flight facility center in Wallops Island, Va.

"It’s about 99 percent above most of the atmosphere, right in-between the atmosphere and space," he said.

"We launch these and the wind takes them wherever they go."

The balloon’s volume is 39 million cubic feet. It’s about 660 feet long and 460 feet wide.

A 300-foot tether hangs below the balloon and holds an instrument package conducting the experiment, said Doug Baugh, a weather specialist with the Grand Junction office of the National Weather Service.

"We were getting all kinds of calls, and we didn’t know what it was either," Baugh said.

Curious people from all over the area called the weather service inquiring about the balloon, he said.

Koehler said the balloon is buoyed in the air with helium. It is made of a plastic material as thin as plastic food wrap. Supportive strands run from the top to the bottom of the balloon.

Though still quite visible from Cortez at 2 p.m., the balloon was located in San Miguel County about 10 miles south of Naturita, at an altitude of 129,800 feet.

By comparison, a typical commercial, cross-country airplane cruises at about 30,000 feet.

The balloon was traveling northwest at 24 mph and was 354 miles from its launch site.

Scientists follow the balloon via tracking systems and bring it down in a remote clearing, Koehler said.

As it approaches earth, an airplane and a ground crew chase the balloon.

For more information about the balloon program, visit the National Scientific Balloon Facility site at http: //master. nsbf.nasa.gov/fred/index.html and http:// lheawww. gsfc.nasa.gov/docs/balloon/balloon_top.html, the Laboratory for High Energy Astrophysics.