title: Planetary science. Risks in space from orbiting debris.
authors.affiliation: Engineering Science Contract Group (ESCG)/ERC at NASA Johnson Space Center, Mail Code JE104, 2224 Bay Area Boulevard, Box 7, Houston, TX 77058, USA. jer-chyi.liou1@jsc.nasa.gov
authors.forename: J C
authors.initials: JC
authors.lastname: Liou
authors.forename: N L
authors.initials: NL
authors.lastname: Johnson