SpaceX will lay off up to 10 percent of its work force, the company said Friday evening. The company characterized the job cuts as “a strategic realignment,” designed to ensure it is positioned to succeed for the long term.

They were announced to employees Friday in an e-mail from company president and chief operating officer Gwynne Shotwell. The company has a work force of more than 6,000 employees.

“To continue delivering for our customers and to succeed in developing interplanetary spacecraft and a global space-based Internet, SpaceX must become a leaner company,” a company official said in a statement.