"It's beautiful, it really is - certainly what we've seen of it so far," said Dr Ashley King.
The UK scientist was in a select group to put first eyes and instruments on the rocky samples that have just been brought back from asteroid Bennu.
The materials, scooped up by a US space agency (Nasa) mission and returned to Earth 17 days ago, are currently being examined in a special lab in Texas.
"We've confirmed we went to the right asteroid," Dr King told BBC News.
The three-day analysis by the Natural History Museum (NHM) expert and five others on the "Quick Look" team showed the black, extraterrestrial powder to be rich in carbon and water-laden minerals.
That's a great sign. There's a theory that carbon-rich (organic), water-rich asteroids similar to Bennu may have been involved in delivering key components to the young Earth system some 4.5 billion years ago. It's potentially how we got the water in our oceans and some of the compounds that were necessary to kick-start life.
The asteroid samples will be used to test these ideas.