Hubble and Webb Find Ancient Solar-System Building Blocks Preserved for Billions of Years
NASA’s Hubble and James Webb space telescopes have found signs that some of the solar system’s earliest building blocks have survived largely unchanged since the system formed.
The observations focused on 27 tiny objects beyond Neptune. Although their small sizes make them difficult to study, Hubble and Webb were able to uncover evidence that these ancient planetesimals have remained remarkably stable for billions of years.
Their preservation offers a rare window into the conditions that existed during the solar system’s formation. At the same time, the objects’ unexpected sizes and numbers do not fit neatly with current theories of planet formation, raising questions about how the early solar system assembled its population of building blocks.
By comparing data from the two telescopes, astronomers are now working to explain how such old and apparently unchanged objects persisted while their wider population presented a challenge to existing formation models.