The search for extraterrestrial life crosses every boundary. It has surpassed the limit of where humans can travel and tested the limits of what we can see. The quest must pass through time as well as space.

Also: Congress.

A House committee convened on Wednesday to take up an abiding mystery of the universe: are we Earthlings alone? After about 90 minutes of testimony, committee chair Lamar Smith of Texas gaveled the hearing to an inconclusive close.

It was not, however, a fruitless outing. In impassioned testimony, witnesses fromNasa, MIT and the Library of Congress described a crossroads in the search for life out there and suggested scientists may be on the verge of a breakthrough.

“This is the first time in human history we have the technological reach to cross the threshold,” said Dr Sara Seager, an MIT professor and 2013 MacArthur “genius grant” recipient. Her work focuses on the detection of “biosignature” gases on distant planets, large volumes of which might indicate life, whether intelligent life or single-cell bacteria.

Seager testified that the James Webb space telescope, scheduled for launch in 2018, and other advances are changing the search for alien life forms. “If life really is everywhere, we actually have a shot at it,” she said.

Nasa announced last month that its Kepler mission had discovered 3,500 potential planets in the Milky Way galaxy, including 647 thought to be the right distance from stars to support inhabitants. The Hubble space telescope has detected water in the atmospheres of five planets outside the solar system,according to two studies released this week.

“The chance is very high” of life elsewhere in the universe, Seager said. “The question is: is there life near here, in our neighborhood of stars? We think the chances are good.”

The witnesses said that sustained funding was needed for scientific research in general and space research in particular. The latest White House budget calls for $17.7bn for Nasa, a slight decrease from 2012 after deeper cuts in the last decade.

“I know that funding is tough, but it’s the best thing that you can do,” said Dr Mary Voytek, senior scientist for astrobiology at Nasa.

“You’ve pretty much indicated [the discovery of] life on other planets is inevitable,” observed Bill Posey, Republican of Florida. “It’s just a matter of time and funding.”