Comets

Comets are small, icy bodies that formed in the cold outer regions of the early Solar System. We are studying cometary material collected by NASA's Stardust spacecraft to learn about the bodies' formation and evolution.

Primordial materials found in comets may preserve details of the early Solar System, including:

• temperatures
• materials available
• heating and cooling rates

Aims

We are studying cometary samples to better understand the conditions and processes operating in the early Solar System. 

Methods

NASA's Stardust mission returned fresh samples of comet 81P/Wild2, providing a unique opportunity to study cometary materials.

The spacecraft travels at a rate of approximately six kilometres per second as it collects the samples. We are studying the effect of this capture speed on the material using laboratory impact simulations.

Results

Our studies of the Stardust samples have found:

• Glycine, a biologically significant molecule
• Abundant inner solar system materials, including some high-temperature components that formed extremely close to the early Sun. This indicates that transport of material was more widespread than previously believed.

We have also identified the characteristics (eg chemistry, size and shape) of material that survived the collection process where such characteristics were still detectable.