What context can I use each word in?
Learn when and how to use these words with these examples!
interplanetary
Example
The interplanetary mission aimed to study the atmosphere of Mars. [interplanetary: adjective]
Example
The spacecraft traveled through interplanetary space to reach Jupiter. [interplanetary: noun]
interstellar
Example
The interstellar medium is the matter and radiation that exists in the space between stars. [interstellar: adjective]
Example
The Voyager spacecraft was launched to explore interstellar space beyond our solar system. [interstellar: noun]
Good things to know
Which word is more common?
Interplanetary is more commonly used than interstellar in everyday language, as it is more relevant to our immediate surroundings and has been the focus of human exploration. Interstellar is more commonly used in the context of astronomy and science fiction.
What’s the difference in the tone of formality between interplanetary and interstellar?
Both interplanetary and interstellar are technical terms used in scientific contexts, and are therefore considered formal language.
