WASHINGTON — The CIA used a futuristic new tool called “Ghost Murmur” to find and rescue the second American airman who was shot down in southern Iran, The Post has learned.

The secret technology uses long-range quantum magnetometry to find the electromagnetic signal of a human heartbeat and pairs the data with artificial intelligence software to isolate the signature from background noise, two sources close to the breakthrough said.

It was the tool’s first use in the field by the spy agency — and was alluded to Monday afternoon by President Trump and CIA Director John Ratcliffe at a White House briefing.

CIA Director John Ratcliffe speaks at a White House briefing Monday on the rescue of a US airman in Iran. Getty Images

“It’s like hearing a voice in a stadium, except the stadium is a thousand square miles of desert,” a source briefed on the program told The Post. “In the right conditions, if your heart is beating, we will find you.”

This source and another with knowledge of Lockheed Martin intelligence collection tools told The Post that Ghost Murmur was developed by Skunk Works, the aerospace giant’s secretive advanced development division. The company declined to comment.

The technology has been successfully tested on Black Hawk helicopters for future potential use on F-35 fighter jets, the second source said.

The missing and wounded weapons systems officer — known publicly only as “Dude 44 Bravo” — was hiding in a mountain crevice after his F-15 jet was shot down late last week, surviving two days in desolate terrain as Iranian troops scoured the area for the American with a bounty on his head.

The wreckage of planes reportedly stuck and then destroyed by US forces in the rescue mission. Handout via Getty Images

Iranian authorities failed to find the US airman before the CIA. Handout via Getty Images

The relatively barren landscape made for “an ideal first operational use” of Ghost Murmur, the first source said.

“The name is deliberate. ‘Murmur’ i