Patent Number: 
Section: claims

1. A radiation-shielding material comprising:hollow glass microspheres containing hydrogen embedded within a binder; anda support structure supporting the binder and microspheres. 2. The radiation-shielding material of claim 1 wherein at least one of the microspheres further comprises a metallic coating. 3. The radiation-shielding material of claim 1 wherein at least one of the microspheres is at least partially filled with helium-3. 4. The radiation-shielding material of claim 1 further comprising a metal powder dispersed in the binder. 5. The radiation-shielding material of claim 1 further comprising metal microspheres dispersed in the binder. 6. The radiation-shielding material of claim 1 further comprising solid glass microspheres dispersed in the binder. 7. A radiation-shielding material comprising:a cast sheet of hollow glass microspheres containing hydrogen embedded within a binder; anda substrate layer supporting the cast sheet. 8. The radiation-shielding material of claim 7 wherein the substrate layer comprises aluminum. 9. The radiation-shielding material of claim 7 wherein the binder comprises epoxy. 10. A radiation-shielding material comprising:a support structure having a honeycomb core structure sandwiched between two face sheets; andhollow glass microspheres containing hydrogen embedded within a binder filling the honeycomb core structure. 11. The radiation-shielding material of claim 10 wherein the face sheets comprise aluminum. 12. The radiation-shielding material of claim 10 wherein the face sheets comprise a composite material.