A rocky history: researchers explain why early meteorites are different from earthly stones

4

From Earth to the moon to Mars, the rocky structures of celestial bodies were built using the very same mixture of oxygen. But for 40 years now, researchers have been noticing something strange: meteorites from the early days of the Solar System are built with a different mixture of oxygen, one where an isotope of the element appeared far more frequently than it ought to. "It’s a big problem," cosmochemist Subrata Chakraborty tells The Verge. "It’s a really, really big problem. If you don’t understand the oxygen isotope, you don’t understand the formation and evolution of the solar system."

"It's a really, really big problem."

In a paper published today in Science, researchers from UC San Diego, led by Chakraborty, are finally explaining part of that mystery. Chakraborty says the distribution of oxygen found in these meteorites was a puzzle: they contained equal amounts of the isotopes oxygen-17 and oxygen-18, rather than having twice as much of the latter like other rocks.

While that may sound like a small difference, Chakraborty says knowing what caused this is important to understanding how the solar system formed. It’s such a puzzle that NASA even sent its Genesis probe out toward the sun in the early 2000s in part to address this very question. But as Chakraborty puts it, difficult experiments and available technology became something of a bottleneck in actually figuring out what was happening before now.

To begin solving it, Chakraborty and his team set out to simulate the environment of the early solar system. In a small chamber they recreated the gaseous makeup of a nebula, and using a type of ultraviolet laser, were able to form their own rocky solids in the way that meteorites would have formed around 4.6 billion years ago. As it turned out, the rocks that Chakraborty’s team created had the very same makeup as the anomalous meteorites.

"You don't need a magic recipe to generate this oxygen anomaly."

The researchers say that meteorites didn’t form this way because of some unexpected behavior present in the early universe. Rather, it appears that the reaction creating them is governed by molecular symmetry, a principle already known to scientists. "You don't need a magic recipe to generate this oxygen anomaly," Mark Thiemens, dean of physical sciences at UC San Diego, said in a statement. "It's just a simple feature of physical chemistry."

Chakraborty says that more research should be done into how minerals form under these circumstances, but learning the workings of oxygen — the third most abundant element in the universe — is a good start. "Oxygen is the building block of all rocky planets," Chakraborty says. "That’s why we are behind oxygen. That’s why NASA is behind oxygen."

More from The Verge

Back to top ^
X
Log In Sign Up

forgot?
Log In Sign Up

Please choose a new Verge username and password

As part of the new Verge launch, prior users will need to choose a permanent username, along with a new password.

Your username will be used to login to Verge going forward.

I already have a Vox Media account!

Verify Vox Media account

Please login to your Vox Media account. This account will be linked to your previously existing Eater account.

Please choose a new Verge username and password

As part of the new Verge launch, prior MT authors will need to choose a new username and password.

Your username will be used to login to Verge going forward.

Forgot password?

We'll email you a reset link.

If you signed up using a 3rd party account like Facebook or Twitter, please login with it instead.

Forgot password?

Try another email?

Almost done,

By becoming a registered user, you are also agreeing to our Terms and confirming that you have read our Privacy Policy.
Spinner.vc97ec6e

Authenticating

Great!

Choose an available username to complete sign up.

In order to provide our users with a better overall experience, we ask for more information from Facebook when using it to login so that we can learn more about our audience and provide you with the best possible experience. We do not store specific user data and the sharing of it is not required to login with Facebook.

tracking_pixel_5345_tracker