Imagine a time when Earth was just a barren rock, waiting for the spark of life. Scientists believe that spark might have come from space—specifically, from asteroids like Bennu. Recent samples brought back by NASA’s OSIRIS-REx mission are shedding light on how water and the building blocks of life could have arrived on our planet.

Bennu, a rocky asteroid, has been a hot topic for years. When the OSIRIS-REx spacecraft collected samples and brought them back to Earth in September 2023, researchers got their hands on a treasure trove of clues. Analysis revealed that Bennu’s rocks are packed with clay rich in water and organic molecules—essential ingredients for life.

Here’s the kicker: the samples also contained rare minerals that form when water evaporates. Think of these as ancient “evaporites,” like the ones found in dried-up lake beds on Earth. But here’s the twist—these minerals vanish when exposed to water, which explains why they’ve never been spotted in meteorites before. Luckily, the OSIRIS-REx team stored the samples in nitrogen, keeping them pristine.

Scientists also found high levels of ammonia and nucleobases—key components of DNA and RNA—in the Bennu samples. These discoveries suggest that Bennu’s parent asteroid was once a watery, muddy world with pockets of briny liquid. These environments could have been the perfect nurseries for complex organic molecules to form.

So, what does this mean for Earth? When asteroids like Bennu crashed into our planet billions of years ago, they might have delivered water and life’s building blocks in one fell swoop. Without these cosmic visitors, Earth might have remained a lifeless rock.

The Bennu samples are a window into the solar system’s early days—and a reminder of how interconnected our universe truly is. Who knew that a piece of space rock could hold the secrets to life itself?