<http://schema.org/alternativeHeadline>
"The Helix Nebula is a complex object composed of dust, ionized material and molecular gas, arrayed in an intricate, flower-like pattern."^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.mnn.com/earth-matters/space/stories/helix-nebula-photo-looks-like-giant-golden-eye>