Since space science is an area that draws attention from scientists, engineers, the public and the media, various expressions emerged in different contexts may bring along unnecessary ambiguities. To make the basic concepts clear, the paper conducts a textual research on the concepts about space science based on a thorough probe of the origin and comparison of space science practices worldwide. For the origin of space science, geophysics and astronomy are the first natural science disciplines to conduct space-borne research, and although space science has not been established as an independent category in China, all its disciplines are at the frontlines of their own parental disciplines, growing strong and bringing even great funding back into their parents. Besides, the paper tries to discriminate the differences between space science and space technology & applications, space science vs. fundamental astronomy, heliospheric pause vs. the boundary of sun's gravity, space science vs. deep space, and science mission vs. operational satellites. As to the future of space science endeavor in China, it proposes that more attention should be paid to space science so as to advance science satellites program and make space science as an open research system and clusters of disciplines. It is expected that the present work is beneficial to related discipline research, project application and public outreach.

space science  /  science satellites  /  discipline research  /  public outreach