(NewsNation) — NASA on Wednesday revealed newly returned samples from a 4.5-billion-year-old asteroid that contains evidence of carbon and water molecules that could “indicate the building blocks of life on Earth.”

The asteroid, Bennu, delivered its first samples last month: a jumble of black dust and rubble that’s the most ever returned to Earth.

Scientists anticipated getting a cupful but are still unsure how much was grabbed from the carbon-rich asteroid almost 60 million miles away. That’s because the main sample chamber has yet to be opened, officials said during an event at Johnson Space Center in Houston.

“It’s been going slow and meticulous, but the science is already starting,” said the mission’s lead scientist, Dante Lauretta of the University of Arizona.

NASA’s OSIRIS-REx spacecraft collected the samples three years ago from the surface of Bennu and then dropped them off sealed in a capsule during a flyby of Earth last month. The expected cupful was far more than the teaspoon or so that Japan brought back from a pair of missions.

Black dust and particles were scattered around the outside edge of the internal sample chamber, according to Lauretta. He said “a whole treasure chest of extraterrestrial material” still needs to be studied. The samples are priceless, the preserved building blocks from the dawn of the solar system.

The findings could help scientists understand how the solar system formed and how life started on Earth.

Bennu has already been found to have the highest percentage of carbon ever measured in an extraterrestrial object at 4.7%, according to Nature.

Astrobiologist Daniel Glavin of NASA’s Goddard Space Flight Center told Nature scientists were excited by the initial results.

“This thing’s loaded with organics,” Glavin said. “This is incredible material.”

Besides carbon, the asteroid rubble holds water in the form of water-bearing clay minerals, Lauretta and others pointed out.

“That is how we think water got to the Earth,” he said. “Minerals like we’re seeing from Bennu landed on Earth 4 billion years ago to 4.5 billion years ago, making our world habitable.”

That was one of the primary reasons for the $1 billion, seven-year mission: to help learn how the solar system — and Earth in particular — formed. “You can’t get more exciting than that,” said NASA Administrator Bill Nelson.

Once the samples are archived, the team will dole out particles to researchers around the world while saving a fair amount for future analysis when better technology should be available.

NASA has another asteroid-chasing spacecraft on a Florida launch pad, ready to blast off later this week. The destination will be a rare asteroid made of metal named Psyche. No samples will be coming back.

The Associated Press contributed to this report.