<http://schema.org/alternativeHeadline>
"The Martian soil is 'similar to basaltic material' often found new volcanoes in Hawaii, including Mauna Kea."^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.mnn.com/earth-matters/space/stories/mars-dirt-similar-to-soil-on-hawaii>