re boom whoosh in article scicom alphacdc com wats scicom alphacdc com bruce watson writes pageos and two echo balloons were inflated with a substance which expanded in vacuum called gas once inflated the substance was no longer needed since there is nothing to cause the balloon to collapse this inflatable structure could suffer multiple holes with no disastrous deflation the balloons were in sufficiently low orbit that they experienced some air resistance when they were finally punctured this preasure and the internal preasure that was needed to maintain a spherical shape against this resistance caused them to catastrophically deflated the large silvered shards that remained were easily visible for some time before reentry though no longer useful as a passive transponder the billboard should pop like a dime store balloon
