Many of the ingredients for life here on Earth may have come from beyond Earth – delivered by asteroids or comets that hit our planet when it was young. And early analysis of samples of an ancient asteroid support that idea.
A mission called Osiris-Rex collected about four ounces of dust and pebbles from the surface of Bennu. The asteroid is about a third of a mile in diameter. Its orbit brings it close to Earth, making it a good target for study.
Osiris-Rex delivered the samples to Earth more than a year ago. Scores of scientists have been studying the samples.
They’ve found that the samples contain lots of carbon, nitrogen, and organic compounds – key ingredients for life. The samples also contain certain types of phosphates, which are part of the chemistry of all life on our planet.
Bennu’s minerals formed in the presence of water. Their composition is a lot like the material at mid-ocean ridges on Earth, where molten rock is bubbling up to form new crust. Those minerals suggest that Bennu is a chip off a larger object – an ocean world. The parent body was blasted apart by a collision with another asteroid. Some of the debris stuck together to form Bennu.
The early results are only a first step. Many more scientists around the world will study fragments of Bennu over the coming months and years. Their work will tell us more about the birth and evolution of this tiny world – as well as our own.
Script by Damond Benningfield