adjective
- relating to or denoting a disk of gas and dust surrounding a young star, from which planets are thought to form
Usage: astronomy; technical
Examples
- Astronomers observed a protoplanetary disk around the young star using the telescope.
- The protoplanetary material gradually coalesced into planetary bodies over millions of years.
- Scientists study protoplanetary systems to understand how planets form.
- A protoplanetary disk typically contains dust, gas, and small rocky fragments.
- The structure of the protoplanetary disk influences the types of planets that develop.