Preface: Advances in asteroid and space debris science and technology-Part 1

The first part of this special issue collects four papers on recent advances on the dynamics of artificial satellites in different orbit regimes around the Earth, followed by four papers on measurements, observations and orbit determination dedicated to space debris. The paper on the criticality of spacecraft index then proposes an index to quantify the criticality of space objects and rank them according to their environmental impact. Three papers follow presenting strategies for the removal of spacecraft from libration points and high elliptical orbits, the active removal of space debris with harpoons and the detumbling of satellites exploiting eddy currents. The last four papers are dedicated to topics relevant to the mitigation of the threat from near-Earth objects and the manipulation of small bodies.