美国航空航天局(NASA)已经退休的专家唐纳德·凯斯勒经常在自己住宅的后院架起望远镜观测太空。凯斯勒是一位天体物理学家,当他被分配到休斯敦美国航空航天局约翰逊航天中心环境影响项目组工作之后,便对人类扔在太空的垃圾产生了浓厚兴趣。太空垃圾可以说是五花八门,包括零部件、各种工具、老化失效的卫星以及火箭推进器等。1978年,凯斯勒发表了一篇有关太空垃圾的论文《人造卫星频繁碰撞: Donald Kessler, a retired NASA expert, often watches telescopes in the backyard of his home. Kessler, an astrophysicist, became interested in disposing of rubbish thrown in space after he was assigned to work at the NASA Johnson Space Center’s Environmental Impact Project Team in Houston. Space junk can be said to be varied, including components, tools, aging launchers and rocket thrusters. In 1978, Kessler published an essay on space junk, "The frequent collision of satellites: