To celebrate the 45th anniversary of the Apollo mission, President Barack Obama hosted a private get-together for all of those involved in the mission at the Oval Office on July 22.

During the event, Obama met with astronauts Michael Collins and Buzz Aldrin, as well as Carol Armstrong, the widow of Neil Armstrong.

The legendary astronaut, who became the first person to step on the moon back on July 20, 1969, died in 2012.

Though the Apollo 11 mission holds an important spot in American history, the 47.5 pounds of lunar rock the crew brought back are still helping researchers learn about the moon and our solar system.

Recently, scientists who analyzed fragments gathered by the Apollo 11, 12, and 16 missions found evidence for a violent collision that likely birthed the moon, according to Reuters.

Obama said in a written statement that the three Apollo 11 crew members have served as testament to American ingenuity and human achievement, and so their efforts in taking the first small steps of our giant leap into the future are being celebrated.

"The United States of America is stronger today thanks to the vision of President Kennedy, who set us on a course for the moon, the courage of Neil, Buzz, and Michael, who made the journey, and all who've worked not only on the Apollo program," said Obama in his statement.

Obama added that men and women of NASA are building on that legacy by preparing for the next giant leap in human exploration, under the leadership of Administrator Charles Bolden.

Among those missions include the first visits of men and women to deep space, to an asteroid, and eventually to Mars.

The White House has set a goal to send a human to an asteroid by 2025, and reach Mars by the mid-2030s.

Before ending the meeting, Obama thanked the astronauts and their families for their service to the country as role models and educators who have inspired "generations of Americans."

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