A green dash within the circle represents a small plane flying at about 14,000 feet over Albuquerque, N.M., air space, a flight that the Air National Guardswoman has been monitoring for nearly 10 minutes because the pilot hasn't been in communication with anyone on the ground.
"Most of the time, it's very innocent," she said, noting that pilots sometimes have their radio turned down, which appears to be case here, because within a few minutes, Maggiolino alerts another desk at the Western Air Defense Sector that the pilot has established communication with the Federal Aviation Administration.
"It's usually nothing," she said.
If the flight had raised concerns, however, fighter jets could have been quickly scrambled to intercept the pilot.
Maggiolino is one of more than two dozen people in the midst of a 12-hour shift on a recent weekday at the sector, which along with the Eastern Defense Sector based in Rome, N.Y., monitors the entire continental United States for threats from the sky as part of the North American Aerospace Defense Command, which has its headquarters at Peterson Air Force Base in Colorado Springs, Colo.
There are also Alaskan and Canadian NORAD sectors, and because it's a bi-national mission, Canadians work alongside Americans in the various sectors.
The Western Air Defense Sector - called WADS by the acronym-loving military members who work there - is housed in a three-story concrete building at Joint Base Lewis-McChord in Washington state.
Dozens of specialists assess information from nearly 200 radar sites covering three-fourths of the country - everything west of the Mississippi River, plus the state of Mississippi - 24 hours a day, and are prepared to engage, and even potentially shoot down, any plane that poses a threat to the country.
"You could drive by and never know what goes on in this building," said Col. Peter Stavros, commander of the sector.
A majority of the approximately 400 people who work at the sector are Air National Guard, but there are also members of the Navy and Army, as well as some federal civilians. And while the program began during the Cold War era, its mission has grown significantly since the Sept. 11, 2001, terrorist attacks.
Before the attacks, their system only tracked potential threats crossing the border into the country through 31 radar sites around the western sector. It now covers the entire interior as well, with more than 300 radar sites, of which, about 195 varying feeds are actively monitored around the clock.
Officials estimate they process about 12,000 air tracks a day here. While the FAA is in charge of controlling the flights, the sector is monitoring them for unusual activity.
The sector's feeds come from ground-based radars of the FAA, mobile radars, airborne warning and control systems aircraft, and Navy off-coast radar. Fighter planes are based at 16 alert sites so that they can quickly intercept a plane if needed.
While jets are often scrambled without the public's knowledge, in 2010, a sonic boom caused by fighter jets accelerating to supersonic speed out of Portland caught many in western Washington state's attention, especially since those jets were scrambled in response to a small float plane that flew into Seattle and landed on Lake Washington during a visit by President Barack Obama.
The pilot wasn't aware the president was in town or the air restrictions that accompany such a high-profile trip.
Capt. Paul Lorkowski is the officer in charge of the weapons desk, the section that scrambles the jets that are based at various locations across the country. He said there are regular training missions or practice scrambles, as well as real-time incidents like the Obama visit.
"There's rarely a day we're not doing something," he said.
Officials with NORAD say that since the 2001 terrorist attacks, fighter jets have been scrambled more than 3,900 times in the U.S. and Canada.
Lorkowski said that last time he scrambled jets for a non-practice run was just a few weeks ago, when there was a report of a passenger with a backpack containing a possible bomb on a commercial flight. The fighter jets intercepted the plane and escorted it to Denver, where the report was found to be false.
Stavros said that the biggest recent scramble that didn't get much media attention occurred on July 4, 2012, when two Russian nuclear-capable bombers flew "very, very close" to the Canadian coastline and were intercepted by U.S. fighter jets off the coast of California.
"We were all sitting enjoying our barbecue on July 4, and we get the call to come in and intercept," he said, noting that the planes turned back without incident in what he says was clearly a posturing move by Russia that was likely in response to a close pass to Russia by U.S. bombers a few weeks earlier. "It was not just a random event."
Maggiolino said that day was a reminder of how quickly blips on a screen can evolve into something much more serious.
"You remember really quickly how important the job is," she said. "No two days are the same. It's always exciting."