A streak of light and a brilliant flash on the western horizon Tuesday morning caught the attention of early risers living across a wide swath of the Pacific Northwest, including much of Montana.

Residents from Judith Gap in central Montana to Spokane, Wash., reported seeing a fireball race across the predawn sky at around 6:40 a.m., followed by a brilliant glow beyond the horizon, leading some to believe the object had impacted nearby.

Matthew Weber, one morning commuter in Helena, reported seeing a large green meteor streak down, resulting in an orange flash that lit up the horizon. From his perspective, the object appeared to hit beyond the “near mountains to the west.”

Another commuter, Kip Davis, believed the object landed near Birdseye. She too saw the pre-dawn sky come alive with a flash of intense color.

“I was heading in on the interstate — heading into town,” said Davis, who lives in the North Hills. “I looked over my right shoulder. It was coming down. It was huge. It went from amber to a bright, brilliant green.”

Early in the day, The Associated Press picked up a story from the Spokesman Review in Spokane, which reported that a pilot with Horizon Air Lines had seen the meteor crash into Earth near State Route 26, some 30 miles southwest of the city.

However, law enforcement officials in Washington said they hadn’t received any reports of a meteor actually hitting the ground. Some in Seattle reported seeing the object as well, raising the question: Where did it actually land?

“The fact that there have been reports that it seemed to impact is unusual in itself,” said William Hiscock, head of the Department of Physics at Montana State University in Bozeman. “That makes this a noteworthy event. But it’s very hard to judge something in the sky in terms of how high it is, how fast it’s going, and how big it is. It may have still been 30 miles up. You just can’t tell with a naked eye.”

Historically, Hiscock said, only a handful of meteorites have ever been found in Montana. Most of those discovered on Earth after impact are collected in Antarctica, where the snow and ice makes recovery easier.

Space dust and small meteors colliding with Earth may not be that uncommon, Hiscock said. In contrast, large meteor impacts are predicted to occur only once every 100 years.

In northern Siberia in 1908, the air burst from one such impact caused an explosion that felled 80 million trees over 830 square miles. The phenomenon had an estimated magnitude similar to a 5.0 earthquake.

“The number of meteors that hit the Earth every year isn’t well understood,” Hiscock said. “From what little I’ve heard, what happened this morning could have been a meteorite or a piece of so-called space junk reentering the atmosphere. Given that it was so bright and so many people saw it, I would lean toward meteor.”

One local witness called 911, fearing that an airplane had gone down. Some wondered if the meteor was somehow related to tonight’s lunar eclipse. Others speculated that perhaps the U.S. military had shot down the Pentagon’s crippled spy satellite earlier than planned.

“That would definitely be a not,” said 2nd Lt. Korry Leverett, public affairs officer with the 341st Space Wing at Malmstrom Air Force Base.

As for tracking the object, Leverett added, “We don’t have any way of tracking or knowing what that would have been. We don’t have any planes around here anymore, so we don’t have any radar.”

Lewis and Clark County Sheriff Cheryl Liedle said her department responded to dozens of calls Tuesday morning.

The department investigated each call, fearing that perhaps an airplane had crashed somewhere west of Helena in the rugged mountain terrain.

“We were running all over the place, trying to find out what fell out of the sky,” she said.

Reporter Martin Kidston: 447-4086 or mkidston@helenair.com