title: Atmospheric radioactive isotopes at orbital altitudes.
abstract: The radioactive isotope 7Be was discovered on the forward-facing side of the LDEF satellite in amounts far exceeding that expected from direct cosmic ray activation of the spacecraft material. This prompted an examination of the production of cosmogenic isotopes in the atmosphere and of the processes by which they may be transported to orbital altitudes and adsorbed by a spacecraft. 7Be is only one of several atmospheric cosmogenic isotopes that might be detectable at orbital altitudes and that might prove to be as useful as tracers of atmospheric circulation processes in the mesosphere and thermosphere as they have been in the lower layers of the atmosphere.
authors.affiliation: Chemistry Department, The University of Alabama in Huntsville, 35899, USA.
authors.forename: J C
authors.initials: JC
authors.lastname: Gregory
mesh_terms: D000327:Adsorption; D000535:Aluminum / Q000737:chemistry / Q000528:radiation effects; D001272:Atmosphere / Q000737:chemistry*; D001608:Beryllium / Q000032:analysis* / Q000737:chemistry; D003359:Cosmic Radiation; D018534:Earth, Planet; D005118:Extraterrestrial Environment; D008962:Models, Theoretical; D011834:Radiation Monitoring / Q000295:instrumentation; D011868:Radioisotopes; D011874:Radiometry; D013026:Space Flight; D018531:Spacecraft
chemical_list: D011868:Radioisotopes; D000535:Aluminum; D001608:Beryllium