In the continuous quest to find cost-effective methods to explore the planets, NASA engineers have risen to the occasion by developing a variety of new balloon methods inspired by centuries-old, solar-heated hot-air balloons, as well as by conventional helium light-gas balloons. For NASA, balloons are of considerable interest as a means of lowering spacecraft to a planet’s surface, delivering instruments to various altitudes and performing aerial photography and other forms of remote-sensing science. Balloons can also potentially conduct explorations faster and cover greater distances than conventional ground-based planetary explorers.