What is an activity outside of a spacecraft called?

The term used to describe an activity outside of a spacecraft is "extravehicular activity," commonly abbreviated as EVA. This designation encompasses various activities performed by astronauts while they are outside their spacecraft, including repairs, scientific experiments, and other tasks necessary for missions in space. The term emphasizes that these actions take place beyond the confines of the vehicle that is typically designed to house and protect the astronauts during their travels through space.

A spacewalk is a colloquial term often used to describe extravehicular activities. While both terms can refer to similar types of activities, extravehicular activity is the more formal and comprehensive term used in the field of aerospace.

Mission refers to the overall objectives and tasks a spacecraft or crew aims to accomplish during a specific flight. Satellite deployment, on the other hand, refers to the specific action of releasing a satellite into orbit, which is just one of many operations that might occur during a mission and does not inherently imply that there are activities being conducted outside a spacecraft.