WASHINGTON — In a brief but highly anticipated speech at the Republican National Convention July 20, former astronaut Eileen Collins called for the U.S. to be “first again” in space, but stopped short of explicitly endorsing the party’s presidential nominee, Donald Trump.

Collins, who spoke for less than four minutes as part of a series of speakers in the first hour of that evening’s convention session in Cleveland, praised the country’s achievements in the Apollo program on the 47th anniversary of the historic Apollo 11 landing, while also suggesting the nation was no longer a leader in space.

“Forty-seven years ago, on this very day, Neil Armstrong and Buzz Aldrin answered that call and they walked on the moon,” she said, referring to the goal set by President John F. Kennedy in 1961 to land humans on the moon by the end of the 1960s. “We landed on the moon to fulfill a leadership challenge, and to explore.”

Collins, who became the first woman to shuttle mission in 1999 and also, in 2005, commanded the first shuttle mission after the Columbia accident, was subtly critical of the decision to cancel the shuttle program. That decision that dates back to the rollout of the Vision for Space Exploration by President George W. Bush in January 2004.

“In 2011, the space shuttle program ended. The last time the United States launched our own astronauts from our own soil was over five years ago,” she said. The final shuttle mission, STS-135, launched on July 8, 2011. “We must do better than that,” she continued, with some cheers from the audience.

“Nations that lead on the frontier lead in the world. We need that visionary leadership again,” she said near the end of her speech. “We need leadership that will make America’s space program first again, and we need leadership that will make America great again.”

Collins did not mention Trump by name in her speech, although the “make America great again” line is also the slogan of the Trump campaign. However, in prepared remarks distributed by the Republican National Committee, her speech included a different final line: “We need leadership that will make America first again. That leader is Donald Trump.”

Collins, who retired from the NASA astronaut corps in 2006, criticized the Obama Administration’s 2010 decision to cancel the Constellation program in testimony at a hearing of the House Science Committee in February on legislation that would restructure the management of the space agency.

“I was shocked, as were my colleagues, first because it was so unexpected, and second because the timing was so close to the end of the space shuttle program it left NASA with no options,” she said.

“I believe program cancellation decisions that are made by bureaucracies behind closed doors, without input by the people, are divisive, damaging, cowardly and many times more expensive in the long run,” she said.

Collins spoke after a video aired marking the Apollo anniversary that also recognized Ohio’s connections to spaceflight, including the Wright Brothers, Neil Armstrong and John Glenn, the first American in space who later represented the state in the U.S. Senate as a Democrat.

“Say an extra prayer that the U.S. will soon reclaim its rightful place as the leader in space exploration,” the video’s narrator said near its conclusion. “Because we will summon the courage and strength to make America great again.”

Trump, during the primary campaign to win the Republican nomination, made only passing references to space in speeches, and his campaign has not issued a space policy. The Republican platform, approved earlier this week, includes only a brief passage about space, much of it endorsing the use of public-private partnerships.

Hillary Clinton, who will formally receive the Democratic Party nomination for president at that party’s convention the week of July 25 in Philadelphia, has also said little about space during the campaign and has not issued a policy. Her campaign did not immediately respond to a request for comment on Collins’ speech.