Researchers say parts of the Moon will be set aside as graveyards for defunct lunar satellites.
Satellite numbers are expected to rise as space agencies expand lunar exploration.
Without an atmosphere, old spacecraft cannot burn up and must be crash-landed.
Uncontrolled impacts risk damaging scientific sites and historic landing areas.
Experts propose designated impact zones far from sensitive regions.
Agencies including NASA and the European Space Agency support planned disposal.
Controlled impacts could also help scientists study the Moon’s internal structure.
